KR20160107102A - Composition for forming resist lower layer film, resist lower layer film, and process for producing patterned substrate - Google Patents

Abstract

Provided is a composition for forming a resist underlayer film which is capable of forming a resist underlayer film enabling the use of PGMEA and the like as a solvent and having excellent solvent-resistance properties, etching-resistance properties, heat-resistance properties, and embeddability. The present invention relates to a composition for forming the resist underlayer film, containing a compound, which has a group including carbon-carbon triple bonds and a partial structure including aromatic rings, and 4 or more of nuclei of benzene in the partial structure forming the aromatic rings, and a solvent. As the partial structure, a first partial structure represented by a chemical formula (1) is desirable. In the chemical formula (1), p1+p2+p3+p4 is desired to be 1 or more and at least one among R1 to R4 is desired to be a monovalent group including carbon-carbon triple bonds. As the group, a propargyl group is desirable. As the partial structure, a second partial structure represented by a chemical formula (2) may be desirable.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a composition for forming a resist underlayer film, a resist underlayer film, and a method for manufacturing a patterned substrate,

The present invention relates to a composition for forming a resist lower layer film, a resist lower layer film, and a method of manufacturing a patterned substrate.

In the production of semiconductor devices, a multi-layer resist process is used to obtain a high degree of integration. In this process, a resist underlayer film is formed by first applying a composition for forming a resist lower layer film on one side of a substrate, and a resist composition is applied on the surface of the under resist film opposite to the substrate side to form a resist film. Then, the resist film is exposed through a mask pattern or the like, and developed with a suitable developer to form a resist pattern. Then, the resist underlayer film is dry-etched using the resist pattern as a mask, and the substrate is further etched using the obtained resist underlayer film pattern as a mask, thereby forming a desired pattern on the substrate to obtain a patterned substrate. The resist underlayer film used in such a multilayer resist process is required to have general characteristics such as optical properties such as refractive index and extinction coefficient, solvent resistance, and etching resistance.

In recent years, further miniaturization of patterns has been made to further increase the degree of integration, and in the above-described multilayer resist process, it is required that the resist underlayer film and the composition for forming the same have excellent properties as described below. With respect to this requirement, various studies have been made on the structure of the compound and the like contained in the composition and the functional groups contained therein (see Japanese Patent Application Laid-Open No. 2004-177668).

In the conventional composition for forming a resist lower layer film, generally, the compound contained therein has a low solubility in a solvent such as propylene glycol monomethyl ether acetate (PGMEA) due to its structure and the like. As a result, there is a problem that it is difficult to form a uniform resist lower layer film as a result of poor applicability to the substrate.

In recent years, a method of forming a hard mask as an intermediate layer on a resist underlayer film in the above-described multilayer resist process has been studied. Specifically, in this method, since the inorganic hard mask is formed on the resist lower layer film by the CVD method, in particular, in the case of the nitride based inorganic hard mask, a high temperature of 300 ° C or lower, usually 400 ° C or higher, High heat resistance is required. However, the conventional resist underlayer film formed of the resist underlayer film composition has insufficient heat resistance, so that the components of the resist underlayer film are sublimated, and the sublimated components are reattached to the substrate, thereby lowering the yield of semiconductor device production .

In recent years, patterns have been increasingly formed on a substrate having a plurality of kinds of trenches, particularly, trenches having different aspect ratios, and the lower resist film to be formed is required to sufficiently fill these trenches. However, in the conventional composition for forming a resist lower layer film, the filling property is insufficient, and the lower resist film to be formed and the hard mask have cavities (voids) and are uneven. As a result, lithography There is a problem that the characteristics are deteriorated.

Japanese Patent Application Laid-Open No. 2004-177668

The object of the present invention is to provide a resist underlayer film forming composition capable of forming a resist underlayer film excellent in solvent resistance, etching resistance, heat resistance and filling property, such as PGMEA, , A resist underlayer film, and a method of manufacturing a patterned substrate.

The present invention for solving the above-mentioned problems is characterized by having a group containing a carbon-carbon triple bond (hereinafter also referred to as "specific group (A)") and having an aromatic ring (hereinafter also referred to as "aromatic ring (A) (Hereinafter also referred to as " partial structure (A) "), and the total number of the benzene nuclei constituting the aromatic ring (A) (Hereinafter also referred to as [A] compound) and a solvent (hereinafter also referred to as " [B] solvent ").

A separate invention for solving the above problems is a resist underlayer film formed from the composition for forming a resist lower layer film.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a resist underlayer film on one side of a substrate; forming a resist pattern on a surface of the under resist film opposite to the substrate; And a step of forming a pattern on the substrate by the etching treatment, wherein the resist underlayer film is formed by the resist underlayer film forming composition.

Here, the term "partial structure" refers to a structure derived from a precursor compound (excluding a compound providing a linking group described later) used for synthesizing the [A] compound. The term " benzene nucleus " refers to a six-membered carbon ring having aromaticity. Each of the six-membered rings constituting the condensed ring is referred to as a benzene nucleus. For example, the number of benzene nuclei in the naphthalene ring is two.

According to the composition for forming a resist lower layer film of the present invention, PGMEA or the like can be used as a solvent, and a resist underlayer film excellent in solvent resistance, etching resistance, heat resistance and filling property can be formed. The resist underlayer film of the present invention is excellent in solvent resistance, etching resistance, heat resistance and filling property. According to the method for producing a patterned substrate of the present invention, a patterned substrate having an excellent pattern shape can be obtained by using the formed resist lower layer film formed as described above. Therefore, they can be suitably used for the production of semiconductor devices, which are expected to be further miniaturized thereafter.

≪ Composition for forming a resist lower layer film &

The composition for forming a resist lower layer film contains a [A] compound and a [B] solvent. The composition for forming a resist lower layer film may contain a [C] acid generator as a suitable component, and may contain other optional components as long as the effect of the present invention is not impaired. Each component will be described below.

<[A] compound>

The [A] compound is a compound having a specific group (A) and also having a partial structure (A). The composition for forming a resist lower layer film can use PGMEA or the like as a solvent because the compound [A] has a specific group (A) and also has a partial structure (A), and can be used for solvent resistance, etching resistance, This excellent resist underlayer film can be formed. The reason why the resist underlayer film forming composition has the above effect because the compound [A] has the above-described structure is not necessarily clear, but can be estimated as follows, for example. That is, the [A] compound has a specific group (A) containing a carbon-carbon triple bond and also has a partial structure (A) containing an aromatic ring (A) By setting the number to a predetermined value or more, solubility in a solvent such as PGMEA becomes high. The composition for forming a resist lower layer film can use such a solvent, and the partial structure (A) of the [A] compound has a certain number or more of benzene nuclei, so that the filling property of the resist lower layer film can be improved. Further, it is considered that the compound [A] having the specific group (A) can form a higher-order crosslinked structure at the time of formation of the resist lower layer film. As a result, the resist underlayer film is excellent in solvent resistance and etching resistance, and further, the partial structure (A) of the compound [A] has a certain number of benzene nuclei.

The [A] compound may have a partial structure other than the partial structure (A) in addition to the partial structure (A). When the [A] compound has a plurality of the partial structures, the plurality of partial structures may be bonded through a linking group (hereinafter, also referred to as "linking group (a)"). Hereinafter, the specific group (A), the partial structure (A), other partial structures and the linking group (a) will be described.

[Specification Period (A)]

The specific group (A) is a group containing a carbon-carbon triple bond. The specific group (A) may be present in the [A] compound, and the bonding position thereof is not particularly limited. The specific group (A) may also be monovalent, and may be a divalent or higher. The specific group (A) may be present in, for example, a partial structure (A) described later or may be in a connecting group. However, from the viewpoint of further improving the heat resistance and filling property of the resist lower layer film, Is more preferably in the partial structure (I) and partial structure (II) described later, and more preferably in the partial structure (I).

As the specific group (A), for example,

An alkynyl group such as an ethynyl group, a propyn-1-yl group, a propargyl group, a butyn-1-yl group, a butyn-3-yl group or a butyn-4-yl group;

A phenylethynyl group, a phenylpropargyl group and the like, and a group containing a triple bond. As the specific group (A), an alkynyl group is preferable and a propargyl group is more preferable from the viewpoint of enhancing the crosslinking easiness of the [A] compound.

The lower limit of the water contained in the specific group (A) is preferably 0.1 mol, more preferably 0.5 mol, more preferably 0.8 mol, and particularly preferably 1.1 mol, per 1 mol of the total partial structure constituting the [A] compound. The upper limit of the water content is preferably 5 moles, more preferably 4 moles, still more preferably 3 moles, and particularly preferably 2.5 moles. When the content of the specific group (A) is in the above range, the crosslinking property of the [A] compound at the time of forming the resist lower layer film can be adjusted to be more appropriate. As a result, the solvent resistance, etching resistance, You can increase your gender. The [A] compound may have one or more specific groups (A).

[Substructure (A)]

The partial structure (A) includes an aromatic ring (A). The total number in the partial structure (A) of the benzene nucleus constituting the aromatic ring (A) is 4 or more.

(Aromatic ring (A))

The aromatic ring (A) is a carbocyclic ring having aromaticity. Examples of the aromatic ring (A) include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a chrysene ring, a tetracene ring, a perylene ring and a pentacene ring.

The lower limit of the carbon number of the aromatic ring (A) is usually 6, preferably 8, and more preferably 10. The upper limit of the number of carbon atoms is preferably 30, more preferably 24, still more preferably 18.

The lower limit of the number of aromatic rings (A) included in the partial structure (A) is usually 1, preferably 2, more preferably 3, and still more preferably 4. The upper limit of the number is preferably 8, more preferably 6.

The lower limit of the total number of carbon atoms in the partial structure (A) of the aromatic ring (A) is usually 16, preferably 20, and more preferably 24. The upper limit of the total number is preferably 50, more preferably 40, and still more preferably 32.

The lower limit of the total number in the partial structure (A) of the benzene nucleus constituting the aromatic ring (A) is 4, preferably 5, and more preferably 6. The upper limit of the total number is preferably 12, more preferably 10, and even more preferably 8. By setting the total number of benzene nuclei in the above range, the solvent resistance, etching resistance and heat resistance of the resist underlayer film can be further increased. The compound [A] may have one or more aromatic rings (A).

A group other than a hydrogen atom such as a specific group (A), a group containing a carbon-carbon double bond, an alkyl group, a hydroxyl group or an alkoxy group may be bonded to the carbon atom constituting the ring of the aromatic ring (A) .

Examples of the partial structure (A) include a first partial structure (hereinafter also referred to as "partial structure (I)") represented by the following chemical formula (1), a second partial structure , &Quot; partial structure (II) &quot;), and the like.

In the formula (1), R ¹ to R ⁴ each independently represent a hydrogen atom, a monovalent group containing a carbon-carbon triple bond or a monovalent group containing a carbon-carbon double bond. m1 and m2 are each independently an integer of 0 to 2; a1 and a2 are each independently an integer of 0 to 9; n1 and n2 are each independently an integer of 0 to 2; a3 and a4 are each independently an integer of 0 to 8; When plural R ¹ to R ⁴ are plural, plural R ¹ may be the same or different and plural R ² may be the same or different and plural R 3 may be the same or different and plural Lt; ⁴ &gt; may be the same or different. p1 and p2 are each independently an integer of 0 to 9; p3 and p4 each independently represent an integer of 0 to 8; p1 + p2 + p3 + p4 is 0 or more. a1 + p1 and a2 + p2 are 9 or less, respectively. a3 + p3 and a4 + p4 are each 8 or less. * Represents a bonding site with a moiety other than the partial structure (I) in the [A] compound.

In the formula (2), R ⁵ to R ⁸ each independently represent a monovalent group containing an alkyl group, a hydroxy group, an alkoxy group, a carbon-carbon triple bond or a carbon-carbon double bond. b1 and b3 are each independently an integer of 0 to 2; b2 and b4 each independently represent an integer of 0 to 3; When a plurality of R ⁵ to R ⁸ are each a plurality, the plurality of R ⁵ may be the same or different and the plurality of R ⁶ may be the same or different, and the plurality of R ⁷ may be the same or different, The plural R &lt; ⁸ &gt; s may be the same or different. q1 and q3 each independently represent an integer of 0 to 2; q2 and q4 are each independently an integer of 0 to 3; q1 + q2 + q3 + q4 is 0 or more. b1 + q1 and b3 + q3 are 2 or less, respectively. b2 + q2 and b4 + q4 are 3 or less, respectively. * Represents a bonding site with a moiety other than the partial structure (II) in the [A] compound.

Examples of the monovalent group containing a carbon-carbon triple bond represented by R ¹ to R ⁴ in the above formula (1) include monovalent ones among the groups exemplified as the specific group (A). Of these, an alkynyl group is preferable, and a propargyl group is more preferable.

As the monovalent group containing a carbon-carbon double bond represented by R ¹ to R ⁴ , for example,

Alkenes such as an ethynyl group, propen-1-yl group, propene-2-yl group, propen-3-yl group, butene-1-yl group, butene- Nil group;

An aromatic ring such as a phenylethenyl group and a phenylpropenyl group, and a group containing a double bond.

It is preferable that at least one of R ¹ to R ⁴ is a group containing a carbon-carbon triple bond, and it is more preferable that R ¹ and R ² are groups containing a carbon-carbon triple bond. By including the specific group (A) in the partial structure (I), the crosslinking property of the [A] compound is further improved, and as a result, the solvent resistance, etching resistance, heat resistance and filling property .

As m1 and m2, 0 and 1 are preferable. As a1 and a2, an integer of 0 to 2 is preferable, 0 and 1 are more preferable, and 1 is more preferable. As a3 and a4, an integer of 0 to 2 is preferable, and 0 and 1 are more preferable, and 0 is more preferable. As p1 and p2, an integer of 0 to 2 is preferable, and 0 and 1 are more preferable, and 1 is more preferable. As p3 and p4, an integer of 0 to 2 is preferable, and 0 and 1 are more preferable, and 0 is more preferable. The lower limit of p1 + p2 + p3 + p4 is preferably 1. The upper limit of p1 + p2 + p3 + p4 is preferably 34, more preferably 18, even more preferably 8, particularly preferably 4, still more preferably 3 and most preferably 2.

Examples of the alkyl group represented by R ⁵ to R ⁸ in the formula (2) include an alkyl group having 1 to 20 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, , Decyl group, and the like.

Examples of the alkoxy group represented by R ⁵ to R ⁸ include an alkoxy group having 1 to 20 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, A decyl group, a decyl group, a decyl group, and a decyloxy group.

Examples of the monovalent group containing a carbon-carbon triple bond represented by R ⁵ to R ⁸ include a monovalent group exemplified as the specific group (A), a monovalent group having an oxygen atom at the terminal end of the bond And the like.

Examples of the group containing a carbon-carbon double bond represented by R ⁵ to R ⁸ include groups similar to the groups exemplified as the groups containing carbon-carbon double bonds of R ¹ to R ^{4 in} the above formula (1) A group having an oxygen atom at the terminal of the bonding side of this group, and the like.

As b1 and b3, 0 and 1 are preferable, and 0 is more preferable. As b2 and b4, an integer of 0 to 2 is preferable, and 0 and 1 are more preferable, and 0 is more preferable. As q1 and q3, 0 and 1 are preferable, and 1 is more preferable. As q2 and q4, an integer of 0 to 2 is preferable, and 0 and 1 are more preferable, and 0 is more preferable. The lower limit of q1 + q2 + q3 + q4 is preferably 1. The upper limit of q1 + q2 + q3 + q4 is preferably 10, more preferably 8, even more preferably 6, particularly preferably 4, still more preferably 3 and most preferably 2.

As R ⁵ to R ⁸ , a monovalent group including an alkyl group, a hydroxy group and a carbon-carbon triple bond is preferable, a monovalent group including a hydroxyl group and a carbon-carbon triple bond is more preferable, and a hydroxyl group and an alkynyloxy group are more preferable And a hydroxy group and a propargyloxy group are particularly preferable.

Examples of the partial structure (I) include a partial structure represented by the following formulas (1-1) to (1-6) (hereinafter also referred to as "partial structures (I-1) to (I-6) . Examples of the partial structure (II) include a partial structure represented by the following general formulas (2-1) to (2-6) (hereinafter also referred to as "partial structures (II-1) to (II-6) .

In the above formulas (1-1) to (1-6), R ^A is a monovalent specific group (A). R ^B is a monovalent group containing a carbon-carbon double bond. p1 to p4 are synonymous with the above formula (1). * Represents a bonding site with a part other than the partial structures (I-1) to (I-6) in the [A] compound.

In the formulas (2-1) to (2-6), R ^A is a monovalent specific group (A). R ^B is a monovalent group containing a carbon-carbon double bond. q1 to q4 are as defined in the above formula (2). * Represents a bonding site with a moiety other than the partial structures (II-1) to (II-6) in the [A] compound.

As partial structure (I), partial structures (I-1), (I-2) and (I-4) are preferable and partial structures (I-1) and (I-2) are more preferable. As the partial structure (II), partial structures (II-1) and (II-2) are preferable, and partial structure (II-1) is more preferable.

The compound [A] preferably has at least one of a partial structure (I) and a partial structure (II) as a partial structure (A), more preferably a partial structure (I) And the partial structure (II). The compound [A] having the above partial structure has higher solubility in a solvent, and as a result, the filling property of the resist underlayer film is further improved.

When the compound [A] has the partial structure (I), the lower limit of the content of the partial structure (I) is preferably 10% by mole, preferably 30% Mol, more preferably 50 mol%. The upper limit of the content is preferably 100 mol%, more preferably 95 mol%, still more preferably 75 mol%. By setting the content ratio of the partial structure (I) within the above range, the solubility of the [A] compound in the solvent can be further increased, and as a result, the heat resistance and the filling property of the resist underlayer film can be made compatible at a higher level.

When the compound [A] has the partial structure (II), the lower limit of the content of the partial structure (II) is preferably 10% by mole, preferably 20% Mol, more preferably 30 mol%. The upper limit of the content is preferably 100 mol%, more preferably 80 mol%, still more preferably 50 mol%. By setting the content ratio of the partial structure (II) within the above range, the content of the polycyclic structure in the [A] compound can be increased, and as a result, the heat resistance and the filling property of the resist underlayer film can be made compatible at a higher level. The compound [A] may have one or more partial structures (A).

[Other partial structures]

Examples of the partial structure other than the partial structure (A) in the compound [A] include partial structures represented by the following formulas (3) to (6), partial structures not containing an aromatic ring .

In the above formula (3), R ⁹ is a monovalent group containing an alkyl group, a hydroxy group, a carbon-carbon triple bond, or a monovalent group containing a carbon-carbon double bond. c1 is an integer of 0 to 5; When c1 is 2 or more, a plurality of R ⁹ may be the same or different. r1 is an integer of 1 to 6; c1 + r1 is 6 or less.

In Formula (4), R ¹⁰ is a monovalent group containing an alkyl group, a hydroxy group, a carbon-carbon triple bond, or a monovalent group containing a carbon-carbon double bond. c2 is an integer of 0 to 7; When c2 is 2 or more, a plurality of R &lt; ¹⁰ &gt; may be the same or different. r2 is an integer of 1 to 8; c2 + r2 is 8 or less.

In the above formula (5), R ¹¹ is a monovalent group containing an alkyl group, a hydroxy group, a carbon-carbon triple bond or a carbon-carbon double bond. c3 is an integer of 0 to 9; When c3 is 2 or more, plural R &lt; ¹¹ &gt; may be the same or different. r3 is an integer of 1 to 10; c3 + r3 is 10 or less.

In Formula (6), R ¹² is a monovalent group containing an alkyl group, a hydroxy group, a carbon-carbon triple bond, or a monovalent group containing a carbon-carbon double bond. c4 is an integer of 0 to 9; When c4 is 2 or more, plural R &lt; ¹² &gt; may be the same or different. r4 is an integer of 1 to 10; c4 + r4 is 10 or less.

As R ^{9 in the} above formula (3), a monovalent group and a hydroxy group containing a carbon-carbon triple bond are preferable, a monovalent group including a carbon-carbon triple bond is more preferable, an alkynyloxy group is more preferable, Particularly preferred is a propargyloxy group. As c1, 1 is preferable. As r1, 1 to 3 is preferable, and 2 is more preferable.

As R ^{10 in} the formula (4), a monovalent group and a hydroxy group containing a carbon-carbon triple bond are preferable, a monovalent group containing a carbon-carbon triple bond is more preferable, an alkynyloxy group is more preferable, Particularly preferred is a propargyloxy group. As c2, 1 is preferable. r2 is preferably 1 to 3, more preferably 2.

The R &lt; ¹¹ &gt; in the above formula (5) is preferably a monovalent group and a hydroxyl group containing a carbon-carbon triple bond, more preferably a monovalent group containing a carbon-carbon triple bond, more preferably an alkynyloxy group, Particularly preferred is a propargyloxy group. As c3, 0 and 1 are preferable, and 0 is more preferable. As r3, 1 to 3 is preferable, and 2 is more preferable.

The R ^{12 in} the formula (6) is preferably a monovalent group and a hydroxy group containing a carbon-carbon triple bond, more preferably a monovalent group containing a carbon-carbon triple bond, more preferably an alkynyloxy group, Particularly preferred is a propargyloxy group. As c4, 0 and 1 are preferable, and 0 is more preferable. r4 is preferably 1 to 3, more preferably 2.

Examples of the partial structure not containing an aromatic ring include a partial structure containing a substituted or unsubstituted chain hydrocarbon group, a partial structure containing a substituted or unsubstituted alicyclic hydrocarbon group, and the like.

The lower limit of the content of the partial structure (A) is preferably 40 mol%, more preferably 50 mol%, further preferably 60 mol%, and more preferably 70 mol%, based on the total partial structure constituting the compound [A] % Is particularly preferable. The upper limit of the content is preferably 100 mol%, more preferably 95 mol%, still more preferably 90 mol%. By setting the content ratio of the partial structure (A) within the above range, the heat resistance and the filling property of the resist underlayer film can be further improved.

When the [A] compound has another partial structure, the lower limit of the content ratio of the other partial structures is preferably 1 mol%, more preferably 5 mol%, based on the total partial structure constituting the [A] More preferably 10 mol%. The upper limit of the content is preferably 60 mol%, more preferably 50 mol%, still more preferably 40 mol%, and particularly preferably 30 mol%. By setting the content ratio of the other partial structures within the above range, the solvent resistance, etching resistance, heat resistance and filling property of the resist underlayer film can be further improved.

[coupler]

[A] When the compound has a plurality of partial structures, these partial structures may be bonded through the linking group (a). When the [A] compound has a plurality of partial structures (A), the plurality of partial structures (A) may be bonded via the connecting group (a).

The linking group (a) includes, for example, a linking group derived from aldehyde. When a linking group derived from an aldehyde is derived from a compound containing one aldehyde group, it usually has a structure of -CHR- (R is a monovalent hydrocarbon group). As R, a hydrogen atom and an aryl group are preferable, a hydrogen atom and a pyrenyl group are more preferable, and a hydrogen atom is more preferable. The linking group derived from formaldehyde is usually -CH ₂ -.

As the aldehyde,

Examples of the compound containing one aldehyde group include formaldehyde, acetaldehyde, propionaldehyde, butylaldehyde, benzaldehyde, naphthalaldehyde, and formalmethylene.

Examples of the compound containing two or more aldehyde groups include 1,4-phenylenedialdehyde and 4,4'-biphenylenedialdehyde.

When the [A] compound has a linking group (a), the lower limit of the content of the linking group (a) relative to 1 mole of the total partial structure constituting the [A] compound is preferably 0.1 mole, more preferably 0.3 mole, Mol is more preferable. The upper limit of the content is preferably 3 moles, more preferably 2 moles, and still more preferably 1.5 moles. By setting the content ratio of the linking group (a) within the above range, the crosslinking density of the [A] compound by the linking group (a) can be more appropriately adjusted. As a result, the solvent resistance, etching resistance, Can be further improved.

Examples of the compound [A] include compounds (hereinafter also referred to as "compounds (A1) to (A11)") having a structure represented by the following formulas (A-1) to .

In the formulas (A-1) to (A-11), R ^A is a monovalent specific group (A).

Among them, the compounds (A1) to (A5) and (A7) to (A11) are preferable as the [A] compound and the compounds (A1), (A3) to (A5) and (A7) to , More preferably compounds (A1) and (A7) to (A11).

The lower limit of the content of the [A] compound is preferably 70% by mass, more preferably 80% by mass, still more preferably 85% by mass, based on the total solid content (components other than the solvent) in the resist underlayer film forming composition Do.

&Lt; Synthesis method of [A] compound &gt;

The compound [A] can be synthesized by a known method. When the compound [A] is a polymer obtained by crosslinking a compound providing the partial structure (A) with an aldehyde, first a phenolic hydroxyl group-containing compound represented by the following formula (1-m) ) And an aldehyde in the presence of an acid in a solvent such as propylene glycol monomethyl ether acetate to obtain a polymer having a phenolic hydroxyl group. Subsequently, the compound [A] can be synthesized by reacting the obtained polymer with a compound forming a specific group (A) such as propargyl bromide in a solvent such as N, N-dimethylacetamide in the presence of a base. The precursor compound may be used alone or in combination of two or more, and the use ratio thereof may be appropriately selected according to the desired performance of the resist underlayer film. The ratio of the precursor compound and the aldehyde can be appropriately selected depending on the desired performance of the resist underlayer film.

In the above formula (1-m), m1, m2, n1, n2 and a1 to a4 are as defined in the above formula (1).

In the above formula (2-m), R ⁵ to R ⁸ and b 1 to b 4 are as defined in the above formula (2).

Examples of the aldehyde include compounds containing one aldehyde group such as formaldehyde (paraformaldehyde), acetaldehyde (paraldehyde), propionaldehyde, butylaldehyde, benzaldehyde, naphthalaldehyde, and formalin; And compounds containing two or more aldehyde groups such as 1,4-phenylenedialdehyde and 4,4'-biphenylenedialdehyde. Among them, a compound containing one aldehyde group is preferable from the viewpoint that the solvent resistance, etching resistance, heat resistance and filling property of the resist underlayer film are further improved by having a more suitable crosslinking structure of the [A] compound, and formaldehyde and formaldehyde More preferable is milleprene, and more preferred is formaldehyde.

Examples of the acid include sulfonic acids such as p-toluenesulfonic acid and benzenesulfonic acid; Sulfuric acid, hydrochloric acid, nitric acid and the like. Among them, sulfonic acid is preferable, and p-toluenesulfonic acid is more preferable.

The lower limit of the amount of the acid to be used is preferably 1 mol, more preferably 5 mol, per 1 mol of the aldehyde. The upper limit of the amount used is preferably 20 moles, more preferably 10 moles.

The lower limit of the reaction temperature for the synthesis reaction of the polymer having a phenolic hydroxyl group is preferably 60 ° C, and more preferably 80 ° C. The upper limit of the reaction temperature is preferably 150 占 폚, and more preferably 120 占 폚. The lower limit of the reaction time of the above reaction is preferably 1 hour, more preferably 4 hours. The upper limit of the reaction time is preferably 24 hours, more preferably 12 hours.

Examples of the base include alkali metal carbonates such as potassium carbonate and sodium carbonate; Alkali metal hydrogencarbonates such as lithium hydrogencarbonate, sodium hydrogencarbonate and potassium hydrogencarbonate; Alkali metal hydroxides such as potassium hydroxide and sodium hydroxide; And alkali metal hydrides such as lithium hydride, sodium hydride and potassium hydride. Of these, alkali metal carbonates are preferable, and potassium carbonate is more preferable.

The lower limit of the amount of the base to be used is preferably 0.1 mol, more preferably 0.5 mol, and still more preferably 0.8 mol, per 1 mol of the compound forming the specific group (A). The upper limit of the amount used is preferably 3 moles, more preferably 2 moles, and still more preferably 1.5 moles.

The lower limit of the reaction temperature for the reaction of reacting the compound forming the specific group (A) to obtain the [A] compound is preferably 50 ° C, and more preferably 60 ° C. The upper limit of the reaction temperature is preferably 130 占 폚, and more preferably 100 占 폚. The lower limit of the reaction time of the above reaction is preferably 1 hour, more preferably 4 hours. The upper limit of the reaction time is preferably 24 hours, more preferably 12 hours.

The [A] compound obtained by synthesis can be purified from the reaction mixture by liquid separation, re-precipitation, recrystallization, distillation and the like. The compound [A] other than the above can also be synthesized in the same manner as described above.

The lower limit of the molecular weight of the [A] compound is preferably 250, more preferably 1,000, still more preferably 2,000, and particularly preferably 3,000. The upper limit of the molecular weight is preferably 10,000, more preferably 7,000, even more preferably 6,000, and particularly preferably 5,000.

When the [A] compound is a polymer, the lower limit of the weight average molecular weight (Mw) of the [A] compound is preferably 1,000, more preferably 2,000, still more preferably 3,000, and particularly preferably 4,000. The upper limit of the Mw is preferably 15,000, more preferably 10,000, even more preferably 8,500, and particularly preferably 7,000.

By setting the molecular weight of the [A] compound within the above range, the solvent resistance, etching resistance, heat resistance and filling property of the resist underlayer film can be further improved.

When the [A] compound is a polymer, the upper limit of the ratio (Mw / Mn ratio) of the [A] compound to the number average molecular weight (Mn) of Mw is preferably 5, more preferably 3, , 1.8 is particularly preferable. The lower limit of the ratio is usually 1, and preferably 1.2. By setting the Mw / Mn ratio of the [A] compound within the above range, the filling property of the resist underlayer film can be further improved.

<[B] Solvent>

The resist underlayer film-forming composition contains [B] solvent. The [B] solvent is not particularly limited as long as it can dissolve or disperse the [A] compound and optionally the optional components contained therein.

 Examples of the solvent [B] include alcohol solvents, ketone solvents, amide solvents, ether solvents, ester solvents and the like. [B] The solvents may be used singly or in combination of two or more.

As the alcohol-based solvent, for example,

Butanol, isobutanol, iso-pentanol, iso-pentanol, sec-pentanol, t-pentanol and the like such as methanol, ethanol, n-propanol, iso-propanol, n- Alcohol solvents;

Ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, And polyhydric alcohol-based solvents.

As the ketone-based solvent, for example,

But are not limited to, acetone, methyl ethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, diethyl ketone, methyl iso butyl ketone, methyl n-pentyl ketone, Aliphatic ketone-based solvents such as ketone, di-iso-butyl ketone, and trimethylnonanone;

Cyclic ketone solvents such as cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone and methylcyclohexanone;

2,4-pentanedione, acetonyl acetone, diacetone alcohol, acetophenone, and methyl n-amyl ketone.

As the amide-based solvent, for example,

Cyclic amide solvents such as 1,3-dimethyl-2-imidazolidinone and N-methyl-2-pyrrolidone;

There may be mentioned a solvent such as formamide, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, And a chain amide-based solvent.

As the ether-based solvent, for example,

Polyhydric alcohol partial ether solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and ethylene glycol dimethyl ether;

Polyhydric alcohol partial ether acetate type solvents such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monoethyl ether acetate;

Di aliphatic ether solvents such as diethyl ether, dipropyl ether, dibutyl ether, butyl methyl ether, butyl ethyl ether and diisobutyl ether;

Aliphatic-aromatic ether solvents such as anisole and phenylethyl ether;

And cyclic ether solvents such as tetrahydrofuran, tetrahydropyrane and dioxane.

As the ester-based solvent, for example,

Propyl acetate, iso-propyl acetate, isobutyl acetate, isobutyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, acetic acid 3-ethyl acetate, methyl lactate, methyl lactate, Examples thereof include carboxylic acid esters such as methoxybutyl, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, methyl acetoacetate and ethyl acetoacetate Based solvent;

lactone solvents such as? -butyrolactone and? -valerolactone;

And carbonic ester solvents such as diethyl carbonate and propylene carbonate.

Of these, ether solvents, ketone solvents and ester solvents are preferable, and ether solvents are more preferable. As the ether solvent, a polyhydric alcohol partial ether acetate solvent and a di aliphatic ether solvent are preferable, a polyhydric alcohol partial ether acetate solvent is more preferable, propylene glycol monoalkyl ether acetate is more preferable, and PGMEA is particularly preferable . As the ketone solvent, a cyclic ketone solvent is preferable, and cyclohexanone and cyclopentanone are more preferable. As the ester solvent, a carboxylic acid ester solvent and a lactone solvent are preferable, a carboxylic acid ester solvent is more preferable, and ethyl lactate is more preferable.

Among the polyvalent alcohol partial ether acetate solvents, propylene glycol monoalkyl ether acetate, especially PGMEA, which is contained in the [B] solvent, can improve the coatability of the composition for forming a resist lower layer film on a substrate such as a silicon wafer . Since the solubility of the [A] compound contained in the resist underlayer film forming composition is high in the solubility in PGMEA and the like, the composition for forming a resist lower layer film is superior in the composition for forming a resist underlayer film by including a polyhydric alcohol partial ether acetate- As a result, the filling property of the resist underlayer film can be further improved. The lower limit of the content of the polyhydric alcohol partial ether acetate solvent in the [B] solvent is preferably 20% by mass, more preferably 60% by mass, even more preferably 90% by mass, and particularly preferably 100% by mass.

<[C] Acid generator>

[C] The acid generator is a component that generates an acid by the action of heat or light and accelerates the crosslinking of the [A] compound. The crosslinking reaction of the [A] compound is accelerated by the presence of the [C] acid generator in the composition for forming a resist lower layer film, so that the hardness of the formed film can be further increased. [C] The acid generator may be used alone or in combination of two or more.

Examples of the acid generator [C] include an onium salt compound, an N-sulfonyloxyimide compound and the like.

Examples of the onium salt compound include a sulfonium salt, a tetrahydrothiophenium salt, and an iodonium salt.

Examples of the sulfonium salts include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, triphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-cyclohexyl Phenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexylphenyldiphenylsulfonium perfluoro-n-octanesulfonate, and 4-cyclohexylphenyldiphenylsulfonium 2-bicyclo [2.2. 1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium Nonafluoro-n-butanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium perfluoro-n-octanesulfonate, 4-methanesulfonylphenyldiphenylsulfone 2-bicyclo [2.2.1] and the like as -1,1,2,2- tetra fluoro hept-2-ethane sulfonate.

Examples of the tetrahydrothiophenium salt include 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-butoxynaphthalen- N-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- 2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- ((4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept- N-butoxynaphthalen-2-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium nonafluoro-n- N-butanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- Hydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate Tetrahydrothiophenium trifluoromethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (3,5-dimethyl- N-butanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- Hydroxyphenyl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate.

Examples of the iodonium salt include diphenyl iodonium trifluoromethane sulfonate, diphenyl iodonium nonafluoro-n-butanesulfonate, diphenyl iodonium perfluoro-n-octanesulfonate, Diphenyl iodonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, bis (4-t-butylphenyl) iodonium trifluoro Methanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium perfluoro- 4-t-butylphenyl) iodonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate.

Examples of the N-sulfonyloxyimide compound include N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (nonafluoro (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- Hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- [2.2.1] hept-5-ene-2,3-dicarboxyimide, and the like.

Of these, as the acid generator, an onium salt compound is preferable, and an iodonium salt is more preferable, and bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate is more preferable .

When the composition for forming a resist lower layer contains a [C] acid generator, the lower limit of the content of the [C] acid generator is preferably 0.1 parts by mass, more preferably 1 part by mass And more preferably 3 parts by mass. The upper limit of the content is preferably 20 parts by mass, more preferably 15 parts by mass, further preferably 10 parts by mass. When the content of the acid generator [C] is within the above range, the crosslinking reaction of the compound [A] can be more effectively promoted.

&Lt; Other optional components &gt;

Examples of other optional components of the composition for forming a resist lower layer film include a crosslinking agent, a surfactant, and an adhesion auxiliary agent.

[Crosslinking agent]

The cross-linking agent is a component that forms cross-linking between components such as the [A] compound in the resist underlayer film forming composition by the action of heat or acid. When the composition for forming a resist lower layer film contains a crosslinking agent, the hardness of the formed film can be increased. The crosslinking agent may be used alone or in combination of two or more.

Examples of the crosslinking agent include compounds having a polyfunctional (meth) acrylate compound, an epoxy compound, a hydroxymethyl group-substituted phenol compound, an alkoxyalkyl group-containing phenol compound, an alkoxyalkylated amino group, an acetone represented by the following formula (7-P) Random copolymers of naphthylene and hydroxymethylacenaphthylene, compounds represented by the following formulas (7-1) to (7-12), and the like.

Examples of the polyfunctional (meth) acrylate compound include trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (Meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerin tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri Acrylate, 1,6-hexanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, Acrylate, diethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, bis (2-hydroxyethyl) Isocyanurate di (meth) acrylate, and the like.

Examples of the epoxy compound include a novolak type epoxy resin, a bisphenol type epoxy resin, an alicyclic epoxy resin, and an aliphatic epoxy resin.

Examples of the hydroxymethyl group-substituted phenol compound include 2-hydroxymethyl-4,6-dimethylphenol, 1,3,5-trihydroxymethylbenzene, 3,5-dihydroxymethyl-4-methoxy Toluene [2,6-bis (hydroxymethyl) -p-cresol] and the like.

 Examples of the alkoxyalkyl group-containing phenol compound include a methoxymethyl group-containing phenol compound and an ethoxymethyl group-containing phenol compound.

Examples of the compound having an alkoxyalkylated amino group include compounds having a plurality of (meth) acryloyl groups in one molecule such as (poly) methylol melamine, (poly) methylol glycoluryl, (poly) methylol benzoguanamine, Containing compound having an active methylol group and at least one of the hydrogen atoms of the hydroxyl group of the methylol group is substituted by an alkyl group such as a methyl group or a butyl group. Further, the compound having an alkoxyalkylated amino group may be a mixture of a plurality of substituted compounds, or an oligomer component which is partially self-condensed.

Of the above formulas (7-6), (7-8), (7-11) and (7-12), Ac represents an acetyl group.

The compounds represented by the above formulas (7-1) to (7-12) can be synthesized by referring to the following references, respectively.

A compound represented by the formula (7-1):

Guo, Qun-Sheng; Lu, Yong-Na; Liu, Bing; Xiao, Jian; Li, Jin-Shan Journal of Organometallic Chemistry, 2006, vol.691, # 6 p.1282-1287

A compound represented by the formula (7-2):

Badar, Y. et al. Journal of the Chemical Society, 1965, pp. 1412-1418

A compound represented by the formula (7-3):

Hsieh, Jen-Chieh; Cheng, Chien-Hong Chemical Engineering (Cambridge, United Kingdom), 2008, # 26 p.2992-2994

The compound represented by the formula (7-4):

Japanese Patent Application Laid-Open No. 5-238990

A compound represented by the formula (7-5):

Bacon, R. G. R .; Bankhead, R. Journal of the Chemical Society, 1963, pp. 839-845

The compounds represented by formulas (7-6), (7-8), (7-11) and (7-12)

Macromolecules 2010, vol43, p2832-2839

The compounds represented by formulas (7-7), (7-9) and (7-10)

Polymer Journal 2008, vol. 40, No. 7, p645-650, and Journal of Polymer Science: Polymer A, Polymer Chemistry, Vol 46, p4949-4958

Among these crosslinking agents, a methoxymethyl group-containing phenol compound, a compound having an alkoxyalkylated amino group and a random copolymer of acenaphthylene and hydroxymethylacenaphthylene are preferable, and a compound having an alkoxyalkylated amino group is more preferable, and 1 , And 3,4,6-tetra (methoxymethyl) glycoluril are more preferable.

When the composition for forming a resist lower layer contains a crosslinking agent, the lower limit of the content of the crosslinking agent is preferably 0.1 part by mass, more preferably 0.5 part by mass, further preferably 1 part by mass, per 100 parts by mass of the [A] , And particularly preferably 3 parts by mass. The upper limit of the content is preferably 100 parts by mass, more preferably 50 parts by mass, further preferably 30 parts by mass, particularly preferably 20 parts by mass. By setting the content of the crosslinking agent within the above range, the crosslinking reaction of the [A] compound can be more effectively caused.

[Surfactants]

The composition for forming a resist lower layer film can improve the coating property by containing a surfactant, and as a result, the uniformity of the coating surface of the formed film can be improved and the occurrence of nonuniform coating can be suppressed. The surfactants may be used singly or in combination of two or more.

Examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene-n-octylphenyl ether, polyoxyethylene-n-nonylphenyl ether, polyethylene glycol And nonionic surfactants such as polyethylene glycol distearate, and the like. As commercial products, KP341 (Shinetsu Chemical Industries Co., Ltd.), Polyfl No. 75, No. 95 (Kyoeisha Yushi Chemical Co., Ltd.), F-top EF101, EF204, EF303, EF352 (Manufactured by TOKEM PRODUCTS CO., LTD.), Megaface F171, Dong F172, Dong F173 (above, DIC Company), Florad FC430, Dong FC431, Dong FC135, DongF3 (above, Sumitomo 3M Company), Asahi Guard AG710, S382, SC101, SC102, SC103, SC104, SC105, SC106 (available from Asahi Glass Co., Ltd.).

When the composition for forming a resist lower layer contains a surfactant, the lower limit of the content of the surfactant is preferably 0.01 parts by mass, more preferably 0.05 parts by mass, and more preferably 0.1 parts by mass, relative to 100 parts by mass of the [A] desirable. The upper limit of the content is preferably 10 parts by mass, more preferably 5 parts by mass, and further preferably 1 part by mass. When the content of the surfactant is within the above range, the applicability of the composition for forming a resist lower layer film can be further improved.

[Adhesion aid]

Adhesion adjuvant is a component that improves adhesion to the substrate. Since the composition for forming a resist lower layer film contains an adhesion auxiliary agent, the adhesion between the lower layer resist film to be formed and the substrate as a base can be improved. The adhesion aid may be used alone or in combination of two or more.

As the adhesion aid, for example, a known adhesion aid can be used.

When the composition for forming a resist lower layer contains the adhesion aid, the lower limit of the content of the adhesion aid is preferably 0.01 parts by mass, more preferably 0.05 parts by mass, and further preferably 0.1 part by mass, relative to 100 parts by mass of the [A] desirable. The upper limit of the content is preferably 10 parts by mass, more preferably 10 parts by mass, and still more preferably 5 parts by mass.

&Lt; Process for producing a composition for forming a resist lower layer film &

The resist underlayer film forming composition is prepared by mixing the [A] compound, the [B] solvent, the [C] acid generator and other optional components, if necessary, in a predetermined ratio, Of a membrane filter or the like. The lower limit of the solid content concentration of the resist lower layer film forming composition is preferably 0.1% by mass, more preferably 1% by mass, still more preferably 2% by mass, and particularly preferably 4% by mass. The upper limit of the solid content concentration is preferably 50% by mass, more preferably 30% by mass, even more preferably 15% by mass, and particularly preferably 8% by mass.

&Lt; Method of manufacturing patterned substrate &

A method of manufacturing a patterned substrate of the present invention comprises:

A step of forming a resist underlayer film on one side of the substrate (hereinafter also referred to as a &quot; resist underlayer film forming step &quot;),

A step of forming a resist pattern on the side of the lower resist film opposite to the substrate (hereinafter, also referred to as a &quot; resist pattern forming step &quot;) and

(Hereinafter also referred to as a &quot; substrate pattern forming step &quot;) of forming a pattern on a substrate by a plurality of times of etching using the resist pattern as a mask. In the above-mentioned method for producing a patterned substrate, the resist underlayer film is formed by the composition for forming a resist lower layer film.

According to the method for producing a patterned substrate, since the above-mentioned composition for forming a resist lower layer film is used, it is possible to form a resist lower layer film excellent in solvent resistance, etching resistance, heat resistance and filling property, , A patterned substrate having an excellent pattern shape can be obtained.

[Resist Underlayer Film Forming Step]

In this step, a resist underlayer film is formed on one side of the substrate by the composition for forming a resist lower layer film. This lower resist film is usually formed by applying a composition for forming a resist lower layer film to one side of the substrate to form a coating film and heating the coating film.

Examples of the substrate include silicon wafers, wafers coated with aluminum, and the like. The method for applying the composition for forming a resist lower layer film to a substrate or the like is not particularly limited and may be carried out by any appropriate method such as rotational coating, soft coating or roll coating.

The heating of the coating film is usually carried out in the atmosphere. The lower limit of the heating temperature is preferably 150 占 폚, more preferably 180 占 폚, and further preferably 200 占 폚. The upper limit of the heating temperature is preferably 500 占 폚, more preferably 380 占 폚, and further preferably 300 占 폚. If the heating temperature is lower than 150 캜, the oxidation crosslinking does not proceed sufficiently, and there is a possibility that necessary properties as a resist underlayer film may not be developed. The lower limit of the heating time is preferably 15 seconds, more preferably 30 seconds, and still more preferably 45 seconds. The upper limit of the heating time is preferably 1,200 seconds, more preferably 600 seconds, and still more preferably 300 seconds.

The lower limit of the oxygen concentration at the time of heating is preferably 5% by volume. When the oxygen concentration at the time of heating is low, oxidation crosslinking of the resist lower layer film does not proceed sufficiently, and there is a fear that required properties as a resist lower layer film may not be developed.

The coating film may be preliminarily heated to a temperature of not less than 60 ° C and not more than 250 ° C before being heated to a temperature of not less than 150 ° C and not more than 500 ° C. The lower limit of the heating time in the preliminary heating is preferably 10 seconds, more preferably 30 seconds. The upper limit of the heating time is preferably 300 seconds, more preferably 180 seconds. By carrying out this preliminary heating, the dehydrogenation reaction can be efficiently advanced by making the film dense by vaporizing the solvent in advance.

In the method for forming a resist lower layer film, usually, the coating film is heated to form a resist lower layer film. In the case where the resist lower layer film forming composition contains a radiation-sensitive acid generator, Whereby the undercoat film can be formed by curing the coating film. Examples of the radiation used in this exposure include electromagnetic waves such as visible light, ultraviolet light, deep ultraviolet light, X-ray and? -Ray, and the like depending on the kind of the radiation- Electron beams, molecular beams, ion beams, and the like.

The lower limit of the average thickness of the lower resist film to be formed is preferably 0.05 占 퐉, more preferably 0.1 占 퐉, and still more preferably 0.5 占 퐉. The upper limit of the average thickness is preferably 5 占 퐉, more preferably 3 占 퐉, and further preferably 2 占 퐉.

After the step of forming the resist lower layer film, if necessary, the step of forming the intermediate layer (intermediate film) may be further provided on the side of the lower resist film opposite to the substrate. The intermediate layer is a layer imparted with the above function to further complement the functions of the resist underlayer film and / or the resist film in forming a resist pattern, or to give a function not possessed by them. For example, when the antireflection film is formed as an intermediate layer, the antireflection function of the resist underlayer film can be further supplemented.

The intermediate layer may be formed of an organic compound or an inorganic oxide. DUV-42, DUV-44, ARC-28 and ARC-29 (manufactured by Brewer Science Co., Ltd.); AR-3 &quot;, &quot; AR-19 &quot; (manufactured by Rohm and Haas Co., Ltd.) and the like. Examples of the inorganic oxide include commercially available products such as "NFC SOG01", "NFC SOG04", and "NFC SOG080" (manufactured by JSR Corporation). In addition, polysiloxane, titanium oxide, alumina oxide, tungsten oxide, or the like formed by the CVD method can be used.

The method of forming the intermediate layer is not particularly limited, but a coating method, a CVD method, or the like can be used, for example. Of these, a coating method is preferable. When the coating method is used, the intermediate layer can be formed continuously after forming the resist lower layer film. The average thickness of the intermediate layer is appropriately selected according to the function required for the intermediate layer, but the lower limit of the average thickness of the intermediate layer is preferably 10 nm, more preferably 20 nm. The upper limit of the average thickness is preferably 3,000 nm, more preferably 300 nm.

[Resist Pattern Forming Step]

In this step, a resist pattern is formed on the side of the lower resist film opposite to the substrate. As a method for carrying out this step, for example, a method of using a resist composition can be given.

Specifically, in the method using the resist composition, a resist composition is applied so that the obtained resist film has a predetermined thickness, and then the resist film is formed by volatilizing the solvent in the coating film by pre-baking.

Examples of the resist composition include a positive-working or negative-working chemically amplified resist composition containing a radiation-sensitive acid generator, a positive resist composition containing an alkali-soluble resin and a quinone diazide-based photosensitive agent, an alkali- And a negative resist composition containing a crosslinking agent.

The lower limit of the solid content concentration of the resist composition is preferably 0.3% by mass, more preferably 1% by mass. The upper limit of the solid concentration is preferably 50% by mass, more preferably 30% by mass. Further, the resist composition is generally filtered by a filter having a pore diameter of about 0.2 mu m, for example, and is provided for forming a resist film. In this step, a commercially available resist composition may be used as it is.

The method of applying the resist composition is not particularly limited, and for example, a spin coat method and the like can be given. The prebaking temperature is appropriately adjusted in accordance with the type of the resist composition to be used, and the lower limit of the temperature is preferably 30 캜, more preferably 50 캜. The upper limit of the temperature is preferably 200 占 폚, and more preferably 150 占 폚. The lower limit of the prebaking time is preferably 10 seconds, more preferably 30 seconds. The upper limit of the time is preferably 600 seconds, more preferably 300 seconds.

Then, the formed resist film is exposed by selective irradiation with radiation. Examples of the radiation used for the exposure include electromagnetic waves such as visible light, ultraviolet light, deep ultraviolet light, X-ray, and? -Ray depending on the kind of the radiation-sensitive acid generator used in the resist composition; Electron beams, molecular beams, ion beams, and the like. Of these, far ultraviolet light is preferable, and KrF excimer laser light (248 nm), ArF excimer laser light (193 nm), F ₂ excimer laser light (wavelength 157 nm), Kr ₂ excimer laser light Laser light (wavelength: 134 nm) and extreme ultraviolet light (EUV, such as a wavelength of 13.5 nm) are more preferable, and KrF excimer laser light, ArF excimer laser light and EUV are more preferable.

Post-baking can be performed after the exposure in order to improve resolution, pattern profile, developability and the like. The post-baking temperature is suitably adjusted in accordance with the type of the resist composition to be used, and the lower limit of the temperature is preferably 50 占 폚, and more preferably 70 占 폚. The upper limit of the temperature is preferably 200 占 폚, and more preferably 150 占 폚. The lower limit of the post-baking time is preferably 10 seconds, more preferably 30 seconds. The upper limit of the time is preferably 600 seconds, more preferably 300 seconds.

Subsequently, the exposed resist film is developed with a developer to form a resist pattern. This phenomenon may be an alkali phenomenon or an organic solvent phenomenon. As the developer, in the case of an alkali development, for example, an inorganic base such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di- Diethylamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo [5.4.0] -7- Undecene, 1,5-diazabicyclo [4.3.0] -5-nonene, and the like. To the alkaline aqueous solution, an appropriate amount of a water-soluble organic solvent such as alcohols such as methanol and ethanol and a surfactant may be added. In the case of organic solvent development, examples of the developer include various organic solvents exemplified as the above-mentioned [B] solvent.

After development with the developing solution, the resist is washed and dried to form a predetermined resist pattern.

As a method for carrying out the present resist pattern forming step, a method using a nanoimprint method, a method using a self-organizing composition, etc. may be used in addition to the method using the above-described resist composition.

[Substrate Pattern Forming Step]

In this step, a pattern is formed on the substrate by a plurality of times of etching using the resist pattern as a mask. In the case where the intermediate layer is not provided, the etching is sequentially performed in the order of the resist lower layer film and the substrate, and in the case of having the intermediate layer, the intermediate layer, the resist lower layer film and the substrate are sequentially etched in this order. Examples of the etching method include dry etching, wet etching and the like. Among these, from the viewpoint of making the shape of the substrate pattern more excellent, dry etching is preferable. For this dry etching, for example, a gas plasma such as an oxygen plasma is used. After the etching, a substrate having a predetermined pattern is obtained.

<Lower resist film>

The resist underlayer film of the present invention is formed from the resist underlayer film forming composition. Since the resist underlayer film is formed of the composition for forming a resist lower layer film described above, it is excellent in solvent resistance, etching resistance, heat resistance and filling property.

Example

Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited to these Examples.

[Mw and Mn]

The Mw and the Mn of the compound [A] were measured using a GPC column (two G2000HXL and one G3000HXL) manufactured by Tosoh Corporation at a flow rate of 1.0 mL / min, an elution solvent of tetrahydrofuran, and a column temperature of 40 캜 Under analytical conditions, the measurement was carried out by means of a gel permeation chromatograph (detector: differential refractometer) using monodispersed polystyrene as a standard.

[Average thickness of membrane]

The average thickness of the film was measured using a spectroscopic ellipsometer (&quot; M2000D &quot; manufactured by J.A.WOOLLAM).

&Lt; Synthesis of [A] compound &gt;

[Synthesis Example 1]

In a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer, 37.16 g (0.11 mol) of 9,9-bis (4-hydroxyphenyl) fluorene and 2.84 g (0.095 mol) of paraformaldehyde were placed under nitrogen. Subsequently, 0.153 g (0.80 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), the solution was poured into a three-necked flask, and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the polymerization reaction solution was poured into a large amount of hexane, and the precipitated polymer was filtered to obtain a compound (PA-1).

Subsequently, 20 g of the obtained compound (PA-1), 80 g of N, N-dimethylacetamide and 16.68 g (0.12 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 14.36 g (0.12 mol) of propargyl bromide was added, and the mixture was stirred for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution to carry out liquid separation, and the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-1). The Mw of the resulting compound (A-1) was 4,500.

[Synthesis Example 2]

In a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer, 37.75 g (0.084 mol) of 9,9-bis (hydroxynaphthyl) fluorene and 2.25 g (0.075 mol) of paraformaldehyde were charged under nitrogen. Subsequently, 0.121 g (0.63 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), the solution was poured into a three-necked flask, and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the polymerization reaction solution was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (PA-2).

Subsequently, 20 g of the obtained polymer (PA-2), 80 g of N, N'-dimethylacetamide and 13.09 g (0.095 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 11.27 g (0.095 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution, and the liquid separation operation was carried out. Then, the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-2). The Mw of the resulting compound (A-2) was 4,500.

[Synthesis Example 3]

A three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer was charged with 35.16 g (0.16 mol) of 1-hydroxypyrrole and 4.84 g (0.16 mol) of paraformaldehyde under nitrogen. Subsequently, 0.245 g (1.29 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), the solution was poured into a three-necked flask, and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the reaction solution was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (PA-3).

Subsequently, 20 g of the obtained compound (PA-3), 80 g of N, N-dimethylacetamide and 13.09 g (0.095 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 11.27 g (0.095 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution, and the liquid separation operation was carried out. Then, the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-3). The Mw of the resulting compound (A-3) was 5,400.

[Synthesis Example 4]

(0.075 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 10.19 g (0.050 mol) of pyrene and 3.40 g of paraformaldehyde were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen (0.113 mol). Subsequently, 0.182 g (0.96 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the reaction solution was poured into a large amount of hexane, and the precipitated polymer was filtered to obtain a compound (PA-4).

Subsequently, 20 g of the obtained compound (PA-4), 80 g of N, N-dimethylacetamide and 11.96 g (0.087 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 10.29 g (0.087 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution, and the liquid separation operation was carried out. Then, the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-4). The Mw of the obtained compound (A-4) was 3,500.

[Synthesis Example 5]

(0.055 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 8.0 g (0.037 mol) of 1-hydroxypyrrole, 0.02 mol of phenol (0.092 mol) of paraformaldehyde and 4.13 g (0.137 mol) of paraformaldehyde. Subsequently, 0.30 g (1.58 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the reaction solution was poured into a large amount of methanol / water (70/30 (mass ratio)) mixed solution, and the precipitated polymer was filtered to obtain a compound (PA-5).

Subsequently, 20 g of the obtained compound (PA-5), 80 g of N, N-dimethylacetamide and 18.92 g (0.137 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 16.29 g (0.137 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution to separate the solution, and the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-5). The Mw of the resulting compound (A-5) was 7,600.

[Synthesis Example 6]

(0.046 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 6.7 g (0.031 mol) of 1-hydroxypyrrole and 0.02 mol of anthracene (0.077 mol) of triethylamine and 3.46 g (0.115 mol) of paraformaldehyde. Subsequently, 0.182 g (0.96 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the reaction solution was poured into a large amount of a methanol / water (70/30 (mass ratio)) mixed solution, and the precipitated polymer was filtered to obtain a compound (PA-6).

Subsequently, 20 g of the obtained compound (PA-6), 80 g of N, N-dimethylacetamide and 18.92 g (0.137 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 16.29 g (0.137 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution to separate the solution, and the organic phase was poured into a large amount of methanol. The precipitated compound was filtered to obtain a compound (A-6). The Mw of the resulting compound (A-6) was 3, 200.

[Synthesis Example 7]

(0.049 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 7.09 g (0.032 mol) of 1-hydroxypyrrole, (0.081 mol) of naphthol and 4.14 g (0.138 mol) of paraformaldehyde. Subsequently, 0.266 g (1.4 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask. The mixture was stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the reaction solution was poured into a large amount of a methanol / water (70/30 (mass ratio)) mixed solution, and the precipitated polymer was filtered to obtain a compound (PA-7).

Subsequently, 20 g of the obtained compound (PA-7), 80 g of N, N-dimethylacetamide and 16.90 g (0.122 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 14.55 g (0.122 mol) of propargyl bromide was added, and the mixture was stirred for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution, and the liquid was separated. The organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-7). The Mw of the obtained compound (A-7) was 3,900.

[Synthesis Example 8]

(0.061 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 12.41 g (0.061 mol) of pyrene and 2.89 g (0.031 mol) of phenol were placed in a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. mol) and 3.22 g (0.107 mol) of paraformaldehyde. Subsequently, 0.251 g (1.32 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), the solution was poured into a three-necked flask and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the reaction solution was poured into a large amount of a methanol / water (70/30 (mass ratio)) mixed solution, and the precipitated polymer was filtered to obtain a compound (PA-8).

Subsequently, 20 g of the obtained compound (PA-8), 80 g of N, N-dimethylacetamide and 11.99 g (0.087 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 10.32 g (0.087 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution to carry out liquid separation. The organic phase was then charged into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-8). The Mw of the obtained compound (A-8) was 5,600.

[Synthesis Example 9]

9.57 g (0.027 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 3.97 g (0.018 mol) of 1-hydroxypyrrole, (0.046 mol) of naphthol and 19.9 g (0.086 mol) of 1-formylpyrrole. Subsequently, 5.19 g (27.3 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of? -Butyrolactone, and this solution was then charged into a three-necked flask and stirred at 130 占 폚 for 9 hours to polymerize. Thereafter, the reaction solution was poured into a large amount of a methanol / water (70/30 (mass ratio)) mixed solution, and the precipitated polymer was filtered to obtain a compound (PA-9).

Subsequently, 20 g of the obtained compound (PA-9), 80 g of N, N-dimethylacetamide and 18.92 g (0.137 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 DEG C, 16.29 g (0.137 mol) of propargyl bromide was added, and the reaction was carried out with stirring for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution to carry out liquid separation, and then the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (A-9). The Mw of the resulting compound (A-9) was 1,500.

[Synthesis Example 10]

(0.075 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 10.19 g (0.050 mol) of pyrene and 3.40 g of paraformaldehyde were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen (0.113 mol). Subsequently, 0.182 g (0.96 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the polymerization reaction solution was poured into a large amount of hexane, and the precipitated compound was filtered to obtain a compound (Pa-1).

Subsequently, 20 g of the compound (Pa-1), 80 g of N, N-dimethylacetamide and 11.96 g (0.087 mol) of potassium carbonate were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, the mixture was heated to 80 占 폚, 11.68 g (0.087 mol) of 4-bromo-1-butene was added, and the mixture was stirred for 6 hours. Thereafter, 40 g of methyl isobutyl ketone and 80 g of water were added to the reaction solution to perform liquid separation, and then the organic phase was poured into a large amount of methanol, and the precipitated compound was filtered to obtain the compound (a-1). The Mw of the obtained compound (a-1) was 4,000.

[Synthesis Example 11]

(0.074 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 9.96 g (0.049 mol) of pyrene and 4.21 g of paraformaldehyde were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen (0.14 mol). Subsequently, 0.20 g (1.05 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), the solution was poured into a three-necked flask, stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the polymerization reaction solution was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (CA-1). The Mw of the obtained compound (CA-1) was 11,000.

[Synthesis Example 12]

(0.083 mol) of 1-hydroxypyrrole, 12.85 g (0.089 mol) of 1-naphthol, 3.35 g (0.036 mol) of phenol and 5.62 g (0.036 mol) of phenol formaldehyde were added to a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. g (0.19 mol). Subsequently, 0.30 g (1.58 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask and stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the polymerization reaction solution was poured into a large amount of a methanol / water (90/10 (mass ratio)) mixed solution, and the precipitated compound was filtered to obtain a compound (CA-2). The Mw of the obtained compound (CA-2) was 5,800.

[Synthesis Example 13]

49.54 g (0.11 mol) of 9,9-bis (hydroxynaphthyl) fluorene and 2.84 g (0.095 mol) of paraformaldehyde were placed in a three-necked flask equipped with a thermometer, a condenser and a mechanical stirrer under nitrogen. Subsequently, 0.153 g (0.80 mmol) of p-toluenesulfonic acid monohydrate was dissolved in 58 g of propylene glycol monomethyl ether acetate (PGMEA), and this solution was added to a three-necked flask. The mixture was stirred at 95 DEG C for 6 hours to polymerize did. Thereafter, the polymerization reaction solution was poured into a large amount of methanol, and the precipitated compound was filtered to obtain a compound (CA-3). The Mw of the obtained compound (CA-3) was 5,200.

&Lt; Preparation of a composition for forming a resist lower layer film &

Components other than the polymer [A] used in the preparation of the resist lower layer film forming composition are shown below.

([B] solvent)

B-1: Propylene glycol monomethyl ether acetate

B-2: Cyclohexanone

([C] acid generator)

C-1: bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate (compound represented by the following formula (C-1)

[Example 1]

And 5 parts by mass of (A-1) as the polymer [A] were dissolved in 95 parts by mass of the (B-1) solvent as the solvent. The obtained solution was filtered with a membrane filter having a pore size of 0.1 mu m to prepare a resist underlayer film forming composition (J-1).

[Examples 2 to 13, Reference Example 1 and Comparative Examples 1 to 3]

A composition for forming each resist lower layer film was produced in the same manner as in Example 1 except that each kind and amount of components shown in Table 1 were used. In Table 1, &quot; - &quot; indicates that the corresponding component is not used.

[Examples 14 to 31, Reference Example 2 and Comparative Examples 4 to 9]

(Formation of resist lower layer film)

The composition for forming each resist lower layer film was coated on a silicon wafer substrate by a spin coat method. Subsequently, the resist underlayer film having a thickness of 200 nm was formed by heating (firing) at 220 DEG C for 60 seconds in an atmospheric air, and substrates each having a resist underlayer film having a resist underlayer film formed thereon were obtained (Examples 14 to 26 and Comparative Examples Examples 4 to 6). In the case of using the resist underlayer film forming composition (j-1) prepared in Reference Example 1 in which the [A] compound does not have a group containing a carbon-carbon triple bond and has a group containing a carbon- Reference Example 2 was used. (J-9) to (J-13) and (CJ-1) to (CJ-3) prepared in Examples 9 to 13 and Comparative Examples 1 to 3, (Baking) for 90 seconds (Examples 27 to 31 and Comparative Examples 7 to 9).

(Formation of resist underlayer film on the stepped substrate)

Each of the resist lower layer film forming compositions prepared above was applied onto a silicon wafer stepped substrate (substrate to be processed) having a depth of 70 nm and a depth of 500 nm by a spin coat method. Thereafter, the resist underlayer film having a thickness of 200 nm was formed by heating (firing) at 220 캜 for 60 seconds in an atmospheric air to obtain a stepped substrate having a resist undercoat film having a resist undercoat film formed thereon (Examples 14 to 26 and Comparative Examples 4 to 6). (J-9) to (J-13) and (CJ-1) to (CJ-3) prepared in Examples 9 to 13 and Comparative Examples 1 to 3, A stepped substrate having a resist undercoat film subjected to heating (firing) for 90 seconds was also obtained (Examples 27 to 31 and Comparative Examples 7 to 9).

<Evaluation>

Various evaluations were performed on the obtained substrate having the resist lower layer film and the stepped substrate having the resist lower layer film in the following procedure. The evaluation results are shown in Table 2. "-" in Table 2 indicates that evaluation was not performed because it was difficult to evaluate the performance of the resist underlayer film due to its low performance.

[Solvent resistance]

The obtained substrate having the resist lower layer film was immersed in cyclohexanone (room temperature) for 1 minute. The average film thickness before and after the immersion was measured to calculate the absolute value of the numerical value obtained from (X-X0) x 100 / X0, where X0 is the average film thickness before immersion and X is the average film thickness after immersion. (%). The solvent resistance was evaluated as "A" (good) when the film thickness change rate was less than 1%, "B" (slightly good) when it was 1% to less than 5%, and "C" .

[Etching Resistance]

The substrate with the resist underlayer film thus obtained was subjected to etching by using an etching apparatus ("TACTRAS" manufactured by Tokyo Electron Co., Ltd.) using CF ₄ / Ar = 110/440 sc cm, PRESS. = 30 MT, HF RF = 500 W, LF RF = = -150 V, RDC = 50%, and 30 seconds. The ratio (nm / min) was calculated from the average film thickness before and after the treatment, and the ratio for Comparative Example 4 was calculated. The etching resistance was evaluated as "A" (very good) when the ratio was 0.95 or more and less than 0.98, "B" (good) when the ratio was 0.98 or more and less than 1.00, or "C" (defective) when the ratio was 1.0 or more.

[Heat resistance]

The prepared resist lower layer film composition was spin-coated on a silicon wafer having a diameter of 8 inches to form a resist lower layer film. Subsequently, this resist lower layer film was heated at 400 DEG C for 150 seconds. After recovering the powder from the substrate, the reduction in mass (%) when heated at a heating rate of 10 ° C / min in a nitrogen atmosphere using a TG-DTA apparatus was called heat resistance. The lower the value of the heat resistance is, the lower the decomposition products of the sublimed product and the resist lower layer film generated during the heating of the lower resist film, and the higher the heat resistance (higher heat resistance). A "(very good) when the mass reduction rate is less than 5%," B "(good) when less than 10%, and" C "(poor) when the mass reduction rate is 10% "He said.

[Filling property]

With respect to the stepped substrate having the obtained resist underlayer film, the presence or absence of voids was evaluated. A "(good) indicating that the void was not identified, and" B "(poor) indicating that the void was confirmed.

As can be seen from the results in Table 2, according to the composition for forming a resist lower layer film of the example, PGMEA and the like can be used as a solvent, and a resist underlayer film excellent in solvent resistance, etching resistance, heat resistance and filling property can be formed.

According to the composition for forming a resist lower layer film of the present invention, PGMEA or the like can be used as a solvent, and a resist underlayer film excellent in solvent resistance, etching resistance, heat resistance and filling property can be formed. The resist underlayer film of the present invention is excellent in solvent resistance, etching resistance, heat resistance and filling property. According to the method for producing a patterned substrate of the present invention, a patterned substrate having an excellent pattern shape can be obtained by using the formed resist lower layer film formed as described above. Therefore, they can be suitably used for the production of semiconductor devices, which are expected to be further miniaturized thereafter.

Claims (13)

A compound having a group containing a carbon-carbon triple bond and having a partial structure containing an aromatic ring, the total number of the partial structures of the benzene nucleus constituting the aromatic ring being 4 or more, and
menstruum
Based on the total weight of the composition. The composition for forming a resist lower layer film according to claim 1, wherein the partial structure has a first partial structure represented by the following formula (1).

(In the formula (1), R ¹ to R ⁴ are each independently a hydrogen atom, a monovalent group containing a carbon-carbon triple bond, or a monovalent group containing a carbon-carbon double bond. Independently, an integer of 0 to 2. a1 and a2 are each independently an integer of 0 to 9. n1 and n2 are each independently an integer of 0 to 2. a3 and a4 are each independently 0 When plural R ¹ to R ⁴ are plural, plural R ^{1 s} may be the same or different, and plural R ^{2 s} may be the same or different, and plural R ^{3 s} may be the same or different. may be different, may be the same are a plurality of R ⁴ or different. p1 and p2 are each independently an integer from 0 to 9. p3 and p4 are each independently, a 0-8 integer. p1 + p2 + p3 + p4 is not less than 0. a1 + p1 and a2 + p2 are each not more than 9. a3 + p3 and a4 + p4 are each not more than 8 (*) Represents a bonding site with a moiety other than the partial structure represented by the formula (1) in the above compound. A resist underlayer film forming method according to claim 2, wherein the p1 + p2 + p3 + p4 in the formula (1) is 1 or more and at least one of R ¹ to R ⁴ is a monovalent group containing a carbon- / RTI &gt; The composition for forming a resist lower layer film according to claim 3, wherein the monovalent group containing the carbon-carbon triple bond is a propargyl group. The composition for forming a resist lower layer film according to claim 1, wherein the partial structure has a second partial structure represented by the following formula (2).

(In the formula (2), R ⁵ to R ⁸ are each independently a monovalent group containing an alkyl group, a hydroxy group, an alkoxy group, a carbon-carbon triple bond, or a monovalent group containing a carbon- and b3 are each independently, an integer from 0 to 2. b2 and b4 are each independently, an integer from 0 to 3. R ⁵ to R ⁸ in this case a plurality of each, a plurality of R ⁵ may be the same or different can have a plurality of R ⁶ may be the same or different, a plurality of R ⁷ may be the same or different, a plurality of R ⁸ s may be the same or different. q1 and q3 are each independently, Q2 and q4 are each independently an integer of 0 to 3. q1 + q2 + q3 + q4 is not less than 0. b1 + q1 and b3 + q3 are not more than 2. b2 + q2 And b4 + q4 are each 3 or less. * Represents a part other than the partial structure represented by the general formula (2) in the above compound It represents the binding site of the.) The composition for forming a resist lower layer film according to claim 5, wherein the compound has the first partial structure and the second partial structure. The method of claim 5, wherein the formula (2) q1 + q2 + q3 + q4 in the 1 or more, R ⁵ to R ⁸ of the at least one is the carbon-forming monovalent group resist lower layer film containing a carbon-carbon triple bond / RTI &gt; The composition for forming a resist lower layer film according to claim 7, wherein the monovalent group containing the carbon-carbon triple bond is a propargyloxy group. The composition for forming a resist lower layer film according to claim 1, wherein the compound has a plurality of the partial structures, and the plurality of partial structures are bonded through a linking group derived from an aldehyde. The composition for forming a resist lower layer film according to claim 1, wherein the compound has a molecular weight of 1,000 or more and 10,000 or less. The composition for forming a resist lower layer film according to claim 1, wherein the solvent comprises a polyvalent alcohol partial ether acetate-based solvent. A resist underlayer film formed from the composition for forming a resist lower layer film according to any one of claims 1 to 11. A step of forming a resist underlayer film on one side of the substrate,
A step of forming a resist pattern on the side of the lower resist film opposite to the substrate, and
And a step of forming a pattern on the substrate by a plurality of times of etching using the resist pattern as a mask,
Wherein the resist underlayer film is formed by the composition for forming a resist underlayer film as set forth in any one of claims 1 to 11. 11. A method for manufacturing a patterned substrate,