Membrane formation methods

Abstract

To provide a technique advantageous for preventing a reduction in filling speed even when a layer in contact with a curable composition is reduced in thickness.SOLUTION: A film forming method for forming a film composed of a curable composition includes: an arrangement step of arranging the curable composition on a ground layer of a substrate having a base material and the ground layer arranged on the base material; a contact step of bringing the curable composition and a mold into contact with each other after the arrangement step; a curing step of curing the curable composition after the contact step; and a separation step of separating the curable composition and the mold from each other after the curing step. In the contact step, gas is present which fills a space between he ground layer and the mold, and the solubility coefficient of the gas in the ground layer is 0.5 kg / m3 atm or more and 10 kg / m3 atm or less.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a film formation method. to To relate to. [Background technology]

[0002] In semiconductor devices and MEMS, the demand for miniaturization is increasing, and optical nanoimprint technology is attracting attention as a microfabrication technology. In optical nanoimprint technology, a mold with a fine surface texture is pressed onto a substrate (wafer) coated with a curable composition, and the curable composition is cured while the mold is pressed against the substrate. This transfers the texture pattern of the mold to the cured film of the curable composition, forming a pattern on the substrate. Optical nanoimprint technology makes it possible to form fine structures on the order of a few nanometers on a substrate.

[0003] Here, we will describe an example of a pattern formation method using optical nanoimprint technology. First, a liquid curable composition is discretely dropped onto a pattern formation area on a substrate. The droplets of curable composition dropped onto the pattern formation area spread out on the substrate. This phenomenon can be called press spreading. Next, a mold with a pattern is pressed against the curable composition on the substrate. As a result, the droplets of curable composition spread out parallel to the substrate in the entire gap between the substrate and the mold by capillary action. This phenomenon can be called spreading. The curable composition is also filled into the recesses that make up the pattern of the mold by capillary action. This filling phenomenon can be called filling. The time until spreading and filling are completed can be called the filling time. After the filling of the curable composition is complete, light is irradiated onto the curable composition to cure it. After that, the mold is pulled away from the cured curable composition. By performing these steps, the pattern of the mold is transferred to the curable composition on the substrate, and a pattern of the curable composition is formed.

[0004] To pattern fine patterns with high precision and a high aspect ratio, techniques such as multilayer curable composition processes and inversion processes can be used. In these methods, the curable composition pattern is first transferred to a layer with high etching resistance (high etching resistance layer), separate from the curable composition, and then the target substrate layer is processed using the high etching resistance layer as an etching mask. Organic materials or silicon-based materials can be used as the material for the high etching resistance layer. As an organic material, SOC (spin-on carbon) with carbon as the main component is sometimes used (Patent Document 1).

[0005] Similarly, in pattern formation using nanoimprinting, a highly etching-resistant layer may be used. Patent Document 2 discloses an inversion process in nanoimprinting, in which SOC is used as the highly etching-resistant layer. Furthermore, in a nanoimprinting process on SOC, an adhesion layer material for nanoimprinting may be applied to the SOC and then imprinting may be performed on top of it (Patent Document 3).

[0006] Furthermore, in the photolithography process for semiconductor device manufacturing, it is also necessary to planarize the substrate. For example, in extreme ultraviolet exposure (EUV), a photolithography technique that has attracted attention in recent years, the depth of focus at which the projection image is formed becomes shallower as miniaturization progresses, so the surface irregularities of the substrate to which the curable composition is applied must be kept to 4 nm or less. Also, in nanoimprint lithography (NIL), another photolithography technique, a level of flatness similar to that of EUV is required to improve filling and line width accuracy (Non-Patent Document 1). As a planarization technique, a technique is known in which droplets of liquid curable composition corresponding to the irregularities are discretely dropped onto a substrate with irregularities, and the curable composition is cured while a mold with a flat surface is pressed onto it to obtain a flat surface (Patent Documents 4 and 5).

[0007] In the above-described pattern formation technology and planarization technology, high throughput is required to improve productivity. However, the processes that require the most time in each step are spreading and filling. In the optical nanoimprint technology using SOC, it is known that the filling rate can be improved by using helium or air as the ambient gas (Non-Patent Document 2).

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Non-Patent Documents

[0009]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

[0010] The inventors of this invention have found that when the layer in contact with the curable composition is thin, the filling rate slows down in a helium or air atmosphere. Therefore, the present invention aims to provide a technology that is advantageous for quickly completing filling even when the layer in contact with the curable composition is thin. [Means for solving the problem]

[0011] A first aspect of the present invention relates to a film forming method for forming a film made of a curable composition using a mold having a surface made of an organic material, the film forming method comprising: a placement step of placing the curable composition on a substrate; a contact step of bringing the curable composition into contact with the surface of the mold after the placement step; a curing step of curing the curable composition after the contact step; and a separation step of separating the curable composition from the mold after the curing step, wherein in the contact step, a gas is present filling the space between the substrate and the mold, the gas contains carbon dioxide at a molar ratio of 25% or more, and the solubility coefficient of the gas in the organic material constituting the surface of the mold is 0.5 kg / m³ 3 ·ATM or more 10kg / m 3 It is less than or equal to ATM. A second aspect of the present invention relates to a film forming method for forming a film made of a curable composition using a mold having a surface made of an organic material, the film forming method comprising: a placement step of placing the curable composition on a substrate; a contact step of bringing the curable composition into contact with the surface of the mold after the placement step; a curing step of curing the curable composition after the contact step; and a separation step of separating the curable composition from the mold after the curing step, wherein in the contact step, a gas is present filling the space between the substrate and the mold, and the solubility coefficient of the gas in the curable composition is 10 kg / m³ 3 The solubility coefficient of the gas in the organic material is less than or equal to atm, and is S[kg / m³]. 3 ·atm], the diffusion coefficient of the gas in the organic material is D[m 2 When [ / s] is used, S·D is 0.5 × 10 -10 The above 10 x 10 -10 The following is 。 [Effects of the Invention]

[0012] According to the present invention, an advantageous technique is provided for suppressing a decrease in filling speed even when the layer in contact with the curable composition is thinned. [Brief explanation of the drawing]

[0013] [Figure 1] A schematic cross-sectional view showing the film formation method according to the first embodiment. [Figure 2] A schematic cross-sectional view showing the case in which the curable composition (A1) is omitted in the film-forming method according to the first embodiment. [Figure 3] A schematic cross-sectional view showing the film formation method according to the second embodiment. [Figure 4] A diagram illustrating an example of theoretical calculation. [Figure 5] A diagram illustrating a method for manufacturing goods. [Figure 6] A diagram illustrating a method for manufacturing goods. [Modes for carrying out the invention]

[0014] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted. ≪First Embodiment≫ [Curable composition] The curable compositions (A1) and (A2) according to this embodiment are compositions having at least one component (a) which is a polymerizable compound. The curable compositions according to this embodiment may further contain a component (b) which is a photopolymerization initiator, a nonpolymerizable compound (c), and a component (d) which is a solvent.

[0015] In this invention, the curable composition (A1) may be omitted.

[0016] Furthermore, in this specification, a cured film means a film obtained by polymerizing and curing a curable composition on a substrate. The shape of the cured film is not particularly limited and may have a patterned shape on its surface.

[0017] <Component (a): Polymerizable compound> Component (a) is a polymerizable compound. Herein, a polymerizable compound is a compound that reacts with polymerization factors (such as radicals) generated from a photopolymerization initiator (component (b)) and forms a film made of a polymer compound through a chain reaction (polymerization reaction).

[0018] Examples of such polymerizable compounds include radical polymerizable compounds. The polymerizable compound that is component (a) may consist of only one type of polymerizable compound, or it may consist of multiple types of polymerizable compounds.

[0019] The radical polymerizable compound is preferably a compound having one or more acryloyl groups or methacryloyl groups, i.e., a (meth)acrylic compound. Therefore, the curable composition according to this embodiment preferably contains a (meth)acrylic compound as component (a), more preferably the main component of component (a) is a (meth)acrylic compound, and most preferably a (meth)acrylic compound. In this description, the main component of component (a) being a (meth)acrylic compound means that 90% by mass or more of component (a) is a (meth)acrylic compound.

[0020] When a radical polymerizable compound is composed of multiple types of compounds having one or more acryloyl groups or methacryloyl groups, it is preferable to include monofunctional (meth)acrylic monomers and polyfunctional (meth)acrylic monomers. This is because combining monofunctional (meth)acrylic monomers and polyfunctional (meth)acrylic monomers yields a cured film with high mechanical strength.

[0021] Examples of monofunctional (meth)acrylic compounds having one acryloyl group or methacryloyl group include phenoxyethyl (meth)acrylate, phenoxy-2-methylethyl (meth)acrylate, phenoxyethoxyethyl (meth)acrylate, 3-phenoxy-2-hydroxypropyl (meth)acrylate, 2-phenylphenoxyethyl (meth)acrylate, 4-phenylphenoxyethyl (meth)acrylate, 3-(2-phenylphenyl)-2-hydroxypropyl (meth)acrylate, EO-modified p-cumylphenol (meth)acrylate, 2-bromophenoxyethyl (meth)acrylate, 2,4-dibromophenoxyethyl (meth)acrylate, 2,4,6-Tribromophenoxyethyl (meth)acrylate, EO-modified phenoxy(meth)acrylate, PO-modified phenoxy(meth)acrylate, polyoxyethylene nonylphenyl ether (meth)acrylate, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, 2-methyl-2-adamantyl (meth)acrylate, 2-ethyl-2-adamantyl (meth)acrylate, bornyl (meth)acrylate, tricyclodecanyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate Acrylate, cyclohexyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate, acryloylmorpholine, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, amyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, pliers Isoamyl(meth)acrylate, hexyl(meth)acrylate, heptyl(meth)acrylate, octyl(meth)acrylate, isooctyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, nonyl(meth)acrylate, decyl(meth)acrylate, isodecyl(meth)acrylate, undecyl(meth)acrylate, dodecyl(meth)acrylate, lauryl(meth)acrylate, stearyl(meth)acrylate, isostearyl(meth)acrylate, benzyl(meth)acrylate, Tetrahydrofurfuryl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, polyethylene glycol mono (meth)acrylate, polypropylene glycol mono (meth)acrylate, methoxyethylene glycol (meth)acrylate, ethoxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, diacetone (meth)acrylamide, isobutoxymethyl (meth)acrylamide, N,Examples include, but are not limited to, N-dimethyl(meth)acrylamide, t-octyl(meth)acrylamide, dimethylaminoethyl(meth)acrylate, diethylaminoethyl(meth)acrylate, 7-amino-3,7-dimethyloctyl(meth)acrylate, N,N-diethyl(meth)acrylamide, and N,N-dimethylaminopropyl(meth)acrylamide.

[0022] Commercially available monofunctional (meth)acrylic compounds include Aronix® M101, M102, M110, M111, M113, M117, M5700, TO-1317, M120, M150, M156 (all manufactured by Toagosei), MEDOL10, MIBDOL10, CHDOL10, MMDOL30, MEDOL30, MIBDOL30, CHDOL30, LA, IBXA, 2-MTA, HPA, and Visco. #150, #155, #158, #190, #192, #193, #220, #2000, #2100, #2150 (all manufactured by Osaka Organic Chemical Industry), Light Acrylate BO-A, EC-A, DMP-A, THF-A, HOP-A, HOA-MPE, HOA-MPL, PO-A, P-200A, NP-4EA, NP-8EA, Epoxy Ester M-600A (all manufactured by Kyoeisha Chemical), KAYARAD (registered trademark) Examples include, but are not limited to, TC110S, R-564, R-128H (all manufactured by Nippon Kayaku), NK ester AMP-10G, AMP-20G (both manufactured by Shin Nakamura Chemical Industry), FA-511A, 512A, 513A (both manufactured by Hitachi Chemical), PHE, CEA, PHE-2, PHE-4, BR-31, BR-31M, BR-32 (all manufactured by Daiichi Kogyo Seiyaku), VP (manufactured by BASF), ACMO, DMAA, DMAPAA (both manufactured by Kojin).

[0023] Furthermore, examples of polyfunctional (meth)acrylic compounds having two or more acryloyl groups or methacryloyl groups include trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate, EO,PO-modified trimethylolpropane tri(meth)acrylate, dimethylol tricyclodecane di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and 1,6-hexane Examples include, but are not limited to, diol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,3-adamantanedimethanol di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tris(acryloyloxy)isocyanurate, bis(hydroxymethyl)tricyclodecane di(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, EO-modified 2,2-bis(4-((meth)acryloxy)phenyl)propane, PO-modified 2,2-bis(4-((meth)acryloxy)phenyl)propane, and EO,PO-modified 2,2-bis(4-((meth)acryloxy)phenyl)propane.

[0024] Commercially available polyfunctional (meth)acrylic compounds include: Yupimer® UV SA1002, SA2007 (both manufactured by Mitsubishi Chemical), Viscoat #195, #230, #215, #260, #335HP, #295, #300, #360, #700, GPT, 3PA (all manufactured by Osaka Organic Chemical Industry), Light Acrylate 4EG-A, 9EG-A, NP-A, DCP-A, BP-4EA, BP-4PA, TMP-A, PE-3A, PE-4A, DPE-6A (all manufactured by Kyoeisha Chemical), and KAYARAD®. Examples include, but are not limited to, PET-30, TMPTA, R-604, DPHA, DPCA-20, -30, -60, -120, HX-620, D-310, D-330 (all manufactured by Nippon Kayaku), Aronix® M208, M210, M215, M220, M240, M305, M309, M310, M315, M325, M400 (all manufactured by Toagosei), and Lipoxy® VR-77, VR-60, VR-90 (all manufactured by Showa Polymer).

[0025] In the above-mentioned group of compounds, (meth)acrylate refers to methacrylate having an acrylate or equivalent alcohol residue. (Meth)acryloyl group refers to a methacryloyl group having an acryloyl group or an equivalent alcohol residue. EO represents ethylene oxide, and EO-modified compound A refers to a compound in which the (meth)acrylic acid residue and alcohol residue of compound A are linked via a block structure of an ethylene oxide group. Furthermore, PO represents propylene oxide, and PO-modified compound B refers to a compound in which the (meth)acrylic acid residue and alcohol residue of compound B are linked via a block structure of a propylene oxide group. <Component (b): Photopolymerization initiator> Component (b) is a photopolymerization initiator. In this specification, a photopolymerization initiator is a compound that senses light of a predetermined wavelength and generates the above-mentioned polymerization factors (radicals). Specifically, a photopolymerization initiator is a polymerization initiator (radical generator) that generates radicals in response to light (infrared rays, visible light, ultraviolet rays, far ultraviolet rays, X-rays, charged particle beams such as electron beams, etc., radiation). Component (b) may consist of one type of photopolymerization initiator or may consist of multiple types of photopolymerization initiators.

[0026] Examples of radical generators include 2,4,5-triarylimidazole dimers which may have substituents such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, and 2-(o- or p-methoxyphenyl)-4,5-diphenylimidazole dimer; benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone (Michler keto Benzophenone derivatives such as N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, and 4,4'-diaminobenzophenone; α-amino aromatic ketone derivatives such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one; 2-ethylanthraquinone, phenanthrene Quinones such as quinone, 2-t-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenantaraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, etc.; benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, etc. Derivatives; Benzoin derivatives such as benzoin, methylbenzoin, ethylbenzoin, and propylbenzoin; Benzyl derivatives such as benzyldimethylketal; Acridine derivatives such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; N-phenylglycine derivatives such as N-phenylglycine; Acetophenone derivatives such as acetophenone, 3-methylacetophenone, acetophenone benzylketal, 1-hydroxycyclohexylphenyl ketone, and 2,2-dimethoxy-2-phenylacetophenone;Thioxanthone derivatives such as thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, and 2-chlorothioxanthone; acylphosphine oxide derivatives such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide; 1,2-octanedione, 1-[4-(phenylthio)-,2-(O- Examples include, but are not limited to, oxime ester derivatives such as benzoyl oxime, ethanolone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,1-(O-acetyloxime); xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, etc.

[0027] Commercially available radical generators include, but are not limited to, Irgacure 184, 369, 651, 500, 819, 907, 784, 2959, CGI-1700, -1750, -1850, CG24-61, Darocur 1116, 1173, Lucirin® TPO, LR8893, LR8970 (all manufactured by BASF), and Yubecryl P36 (manufactured by UCB).

[0028] Among these, component (b) is preferably an acylphosphine oxide polymerization initiator. In addition, among the above examples, the acylphosphine oxide polymerization initiators are acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0029] In this embodiment, it is preferable that the curable composition (A1) is substantially photoreactive. For this reason, the blending ratio of component (b) in the curable composition (A1) is preferably less than 0.1% by mass, more preferably 0.01% by mass or less, and even more preferably 0.001% by mass or less, based on the total mass of component (a), component (b), and component (c) described later, i.e., the total mass of all components excluding the solvent component (d). By setting the blending ratio of component (b) to less than 0.1% by mass, the curable composition (A1) is substantially photoreactive. As a result, photocuring due to leaked light does not occur, and a pattern with few unfilled defects can be obtained even with a short filling time in adjacent shots. The curing reaction of the curable composition (A1) in the shot will be described later.

[0030] The blending ratio of component (b) in the curable composition (A2) is preferably 0.1% by mass or more and 50% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, and even more preferably 1% by mass or more and 20% by mass or less, based on the total mass of component (a), component (b), and component (c) described later, i.e., the total mass of all components excluding solvent component (d). By setting the blending ratio of component (b) to 0.1% by mass or more, the curing rate of the composition can be increased and the reaction efficiency can be improved, and by setting it to 50% by mass or less, the resulting cured film can be made to have a certain degree of mechanical strength. <Component (c): Non-polymerizable compound> In addition to components (a) and (b) described above, the curable compositions (A1) and (A2) according to this embodiment may further contain a non-polymerizable compound as component (c) to the extent that it does not impair the effects of this embodiment, depending on the purpose. Examples of such component (c) include compounds that do not have polymerizable functional groups such as (meth)acryloyl groups and do not have the ability to sense light of a predetermined wavelength and generate the above polymerization factors (radicals). Examples include sensitizers, hydrogen donors, internally added mold release agents, antioxidants, polymer components, and other additives. Multiple types of the above compounds may be contained as component (c).

[0031] Sensitizers are compounds added as needed to accelerate polymerization reactions or improve the conversion rate. Sensitizers may be used individually or in combination of two or more types.

[0032] Examples of sensitizers include sensitizing dyes. Sensitizing dyes are compounds that are excited by absorbing light of a specific wavelength and interact with the photopolymerization initiator, which is component (b). The interactions described here refer to energy transfer and electron transfer from the excited sensitizing dye to the photopolymerization initiator, which is component (b). Specific examples of sensitizing dyes include, but are not limited to, anthracene derivatives, anthraquinone derivatives, pyrene derivatives, perylene derivatives, carbazole derivatives, benzophenone derivatives, thioxanthone derivatives, xanthone derivatives, coumarin derivatives, phenothiazine derivatives, camphaquinone derivatives, acridine dyes, thiopyrillium salt dyes, merocyanine dyes, quinoline dyes, styrylquinoline dyes, ketocoumarin dyes, thioxanthene dyes, xanthene dyes, oxonol dyes, cyanine dyes, rhodamine dyes, and pyrylium salt dyes.

[0033] The hydrogen donor is a compound that reacts with the initiation radical generated from the photopolymerization initiator (component (b)) and the radicals at the polymerization growth ends to generate more reactive radicals. It is preferable to add the hydrogen donor when the photopolymerization initiator (component (b)) is a photoradical generator.

[0034] Specific examples of such hydrogen donors include, but are not limited to, amine compounds such as n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthiourea, s-benzylisothiuronium-p-toluenesulfinate, triethylamine, diethylaminoethyl methacrylate, triethylenetetramine, 4,4'-bis(dialkylamino)benzophenone, ethyl N,N-dimethylaminobenzoate, isoamyl N,N-dimethylaminobenzoate, pentyl-4-dimethylaminobenzoate, triethanolamine, and N-phenylglycine, as well as mercapto compounds such as 2-mercapto-N-phenylbenzimidazole and mercaptopropionate. The hydrogen donor may be used alone or in mixtures of two or more types. Furthermore, the hydrogen donor may also function as a sensitizer.

[0035] To reduce the interfacial bonding force between the mold and the curable composition, that is, to reduce the release force in the release step described later, an internally added release agent can be added to the curable composition. In this specification, "internally added" means that it is added to the curable composition in advance before the curable composition placement step. As the internally added release agent, surfactants such as silicone-based surfactants, fluorine-based surfactants, and hydrocarbon-based surfactants can be used. However, in this embodiment, as described later, there are restrictions on the amount of fluorine-based surfactants that can be added. In this embodiment, the internally added release agent is assumed to be nonpolymerizable. One type of internally added release agent may be used alone, or two or more types may be used in mixture form.

[0036] Examples of fluorinated surfactants include polyalkylene oxide (polyethylene oxide, polypropylene oxide, etc.) adducts of alcohols having a perfluoroalkyl group, and polyalkylene oxide (polyethylene oxide, polypropylene oxide, etc.) adducts of perfluoropolyethers. Fluorinated surfactants may also have hydroxyl groups, alkoxy groups, alkyl groups, amino groups, thiol groups, etc., in part of their molecular structure (e.g., terminal groups). Examples include pentadecaethylene glycol mono-1H,1H,2H,2H-perfluorooctyl ether.

[0037] Commercially available fluorine-based surfactants may be used. Examples of commercially available products include Megafac® F-444, TF-2066, TF-2067, TF-2068, abbreviated DEO-15 (all manufactured by DIC), Florard FC-430, FC-431 (all manufactured by Sumitomo 3M), Surflon® S-382 (manufactured by AGC), EFTOP EF-122A, 122B, 122C, EF-121, EF-126, EF-127, MF-100 (all manufactured by Tochem Products), PF-636, PF-6320, PF-656, PF-6520 (all manufactured by OMNOVA). Examples include Solutions (manufactured by Daikin Industries), Unidyne® DS-401, DS-403, DS-451 (all manufactured by Daikin Industries), and Futergent® 250, 251, 222F, 208G (all manufactured by Neos).

[0038] Furthermore, the internally added release agent may also be a hydrocarbon-based surfactant. Examples of hydrocarbon-based surfactants include alkyl alcohol polyalkylene oxide adducts and polyalkylene oxides, which are obtained by adding an alkylene oxide with 2 to 4 carbon atoms to an alkyl alcohol with 1 to 50 carbon atoms.

[0039] Examples of alkyl alcohol polyalkylene oxide adducts include methyl alcohol ethylene oxide adducts, decyl alcohol ethylene oxide adducts, lauryl alcohol ethylene oxide adducts, cetyl alcohol ethylene oxide adducts, stearyl alcohol ethylene oxide adducts, and stearyl alcohol ethylene oxide / propylene oxide adducts. The terminal group of the alkyl alcohol polyalkylene oxide adduct is not limited to a hydroxyl group that can be produced simply by adding a polyalkylene oxide to an alkyl alcohol. This hydroxyl group may be substituted with other substituents, such as polar functional groups like carboxyl groups, amino groups, pyridyl groups, thiol groups, and silanol groups, or hydrophobic functional groups like alkyl groups and alkoxy groups.

[0040] Examples of polyalkylene oxides include polyethylene glycol, polypropylene glycol, their mono or dimethyl ethers, mono or dioctyl ethers, mono or dinonyl ethers, mono or didecyl ethers, monoadipic acid esters, monooleic acid esters, monostearate esters, monosuccinate esters, and the like.

[0041] Alkyl alcohol polyalkylene oxide adducts may be commercially available. Examples of commercially available products include: polyoxyethylene methyl ether (methyl alcohol ethylene oxide adduct) (BLAUNON MP-400, MP-550, MP-1000) manufactured by Aoki Oil & Fat Industry Co., Ltd.; polyoxyethylene decyl ether (decyl alcohol ethylene oxide adduct) (FINESURF D-1303, D-1305, D-1307, D-1310) manufactured by Aoki Oil & Fat Industry Co., Ltd.; polyoxyethylene lauryl ether (lauryl alcohol ethylene oxide adduct) (BLAUNON EL-1505) manufactured by Aoki Oil & Fat Industry Co., Ltd.; polyoxyethylene cetyl ether (cetyl alcohol ethylene oxide adduct) (BLAUNON CH-305, CH-310) manufactured by Aoki Oil & Fat Industry Co., Ltd.; and polyoxyethylene stearyl ether (stearyl alcohol ethylene oxide adduct) (BLAUNON Examples include SR-705, SR-707, SR-715, SR-720, SR-730, SR-750), random polymerization type polyoxyethylene polyoxypropylene stearyl ether from Aoki Oil & Fat Industry (BLAUNON SA-50 / 50 1000R, SA-30 / 70 2000R), polyoxyethylene methyl ether from BASF (Pluriol® A760E), and polyoxyethylene alkyl ether from Kao (Emulgen series). In addition, commercially available polyalkylene oxides may be used, such as ethylene oxide-propylene oxide copolymer from BASF (Pluronic PE6400).

[0042] Fluorine-based surfactants exhibit excellent mold release force reduction effects and are therefore effective as internally added mold release agents. The blending ratio of component (c), excluding the fluorine-based surfactant, in the curable composition is preferably 0% to 50% by mass, relative to the total mass of components (a), (b), and (c), i.e., the total mass of all components excluding the solvent. More preferably, it is 0.1% to 50% by mass, and even more preferably 0.1% to 20% by mass. By setting the blending ratio of component (c), excluding the fluorine-based surfactant, to 50% by mass or less, the resulting cured film can be made to have a certain degree of mechanical strength. <Component (d): Solvent> The curable composition according to this embodiment may contain a solvent as component (d). Component (d) is not particularly limited as long as it is a solvent in which components (a), (b), and (c) dissolve. Preferred solvents are those with a boiling point of 80°C or higher and 200°C or lower at atmospheric pressure. More preferably, the solvent has at least one of the following: an ester structure, a ketone structure, a hydroxyl group, or an ether structure. Specifically, these are solvents selected individually or in mixtures thereof from propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, cyclohexanone, 2-heptanone, γ-butyrolactone, and ethyl lactate.

[0043] The curable composition (A1) according to this embodiment preferably contains component (d). This is because, as will be described later, spin coating is preferred as the method for applying the curable composition (A1) to the substrate. <Temperature when compounding the curable composition> When preparing the curable compositions (A1) and (A2) of this embodiment, at least component (a) and component (b) are mixed and dissolved under predetermined temperature conditions. Specifically, this is done in the range of 0°C to 100°C. The same applies when components (c) and (d) are also included. <Viscosity of curable composition> The curable compositions (A1) and (A2) according to this embodiment are preferably liquids. This is because, in the mold contact process described later, the spreading and filling of the curable compositions (A1) and / or (A2) can be completed quickly, meaning the filling time is short.

[0044] The viscosity at 25°C of the mixture of components of the curable composition (A1) according to this embodiment, excluding the solvent (component (d)), is preferably 1 mPa·s or more and 1000 mPa·s or less. More preferably, it is 1 mPa·s or more and 500 mPa·s or less, and even more preferably, it is 1 mPa·s or more and 100 mPa·s or less.

[0045] The viscosity at 25°C of the mixture of components of the curable composition (A2) according to this embodiment, excluding the solvent (component (d)), is preferably 1 mPa·s or more and 100 mPa·s or less. More preferably, it is 1 mPa·s or more and 50 mPa·s or less, and even more preferably, it is 1 mPa·s or more and 12 mPa·s or less.

[0046] By setting the viscosity of curable composition (A1) to 1000 mPa·s or less, or the viscosity of curable composition (A2) to 100 mPa·s or less, spreading and filling can be completed quickly when curable compositions (A1) and (A2) are brought into contact with the mold. In other words, by using the curable compositions according to this embodiment, the optical nanoimprint method can be performed with high throughput. Furthermore, pattern defects due to insufficient filling are less likely to occur. In addition, by setting the viscosity to 1 mPa·s or more, uneven coating is less likely to occur when curable compositions (A1) and (A2) are applied to the substrate. Furthermore, when curable compositions (A1) and (A2) are brought into contact with the mold, it is less likely that the curable compositions (A1) and (A2) will flow out from the edges of the mold. <Surface tension of curable compositions> The surface tension of the curable compositions (A1) and (A2) according to this embodiment is preferably 5 mN / m or more and 70 mN / m or less at 23°C for the composition of components excluding the solvent (component (d)). More preferably, it is 7 mN / m or more and 50 mN / m or less, and even more preferably, 10 mN / m or more and 40 mN / m or less. Here, the higher the surface tension, for example, if it is 5 mN / m or more, the stronger the capillary force, so when the curable composition (A1) and / or (A2) is brought into contact with the mold, filling (spreading and filling) is completed in a short time. Furthermore, by setting the surface tension to 70 mN / m or less, the cured film obtained by curing the curable composition becomes a cured film with a smooth surface.

[0047] In this embodiment, it is preferable that the surface tension of the curable composition (A1) excluding the solvent (component (d)) is higher than the surface tension of the curable composition (A2) excluding the solvent (component (d)). This is because, before the mold contact process, the press spread of the curable composition (A2) is accelerated by the Marangoni effect described later (the droplet spreads over a wide area), shortening the time required for spreading during the mold contact process described later, and consequently shortening the filling time. The Marangoni effect is a phenomenon of free surface movement caused by local differences in the surface tension of liquids. Driven by the difference in surface tension, or surface energy, a liquid with lower surface tension diffuses to cover a wider area. In other words, if a curable composition (A1) with high surface tension is applied to the entire surface of the substrate, and a curable composition (A2) with low surface tension is dropped onto it, the press spread of the curable composition (A2) is accelerated. <Contact angle of curable composition> The contact angles of the curable compositions (A1) and (A2) according to this embodiment are preferably 0° to 90° with respect to both the substrate surface and the mold surface, and particularly preferably 0° to 10°, for the compositions of the components excluding the solvent (component (d)). If the contact angle is greater than 90°, capillary forces act in a negative direction (a direction that causes contraction of the contact interface between the mold and the curable composition) inside the mold pattern and in the gap between the substrate and the mold, which may result in incomplete filling. A lower contact angle results in stronger capillary forces and therefore a faster filling speed. <Impurities present in the curable composition> The curable compositions (A1) and (A2) according to this embodiment are preferably free of impurities as much as possible. The impurities referred to here mean those other than the aforementioned components (a), (b), (c), and (d). Therefore, the curable compositions according to this embodiment are preferably obtained through a purification process. Such a purification process may include filtration using a filter.

[0048] When performing filtration using a filter, it is preferable to mix the aforementioned components (a), (b), and (c), and then filter the mixture using, for example, a filter with a pore size of 0.001 μm to 5.0 μm. When performing filtration using a filter, it is even more preferable to perform it in multiple stages or repeat it many times. The filtered liquid may also be filtered again. Multiple filters with different pore sizes may be used for filtration. Filters made of polyethylene resin, polypropylene resin, fluororesin, nylon resin, etc., can be used, but are not particularly limited. By going through such a purification process, impurities such as particles mixed in the curable composition can be removed. This prevents the occurrence of irregularities and pattern defects in the cured film obtained after curing the curable composition due to impurities such as particles.

[0049] Furthermore, when using the curable composition according to this embodiment for manufacturing semiconductor integrated circuits, it is preferable to avoid, as much as possible, the inclusion of metal atom-containing impurities (metallic impurities) in the curable composition in order to avoid interfering with the operation of the product. In such cases, the concentration of metal impurities in the curable composition is preferably 10 ppm or less, and more preferably 100 ppb or less. [Substrate (Base Material)] In this specification, a member on which a substrate layer is placed is described as a substrate or base material. A structure including a member on which a substrate layer is placed and the substrate layer placed on top of the object may also be described as a substrate; in such cases, to avoid confusion, the member on which the substrate layer is placed should be understood as a base material.

[0050] The substrate on which the underlayer is placed is the substrate to be processed, and typically a silicon wafer is used. The substrate may have the layer to be processed on its surface. The substrate may also have other layers formed beneath the layer to be processed. Furthermore, if a quartz substrate is used as the substrate, a replica (mold replica) of a quartz imprint mold can be manufactured. However, the substrate is not limited to silicon wafers or quartz substrates. The substrate can be arbitrarily selected from among those known as semiconductor device substrates, such as aluminum, titanium-tungsten alloy, aluminum-silicon alloy, aluminum-copper-silicon alloy, silicon oxide, and silicon nitride. The surface of the substrate or layer to be processed may have improved adhesion to the curable compositions (A1) and (A2) by surface treatment such as silane coupling treatment, silazane treatment, or deposition of an organic thin film. As a specific example of the organic thin film deposited as a surface treatment, for example, the adhesion layer described in Patent Document 6 can be used. [Base layer] The underlayer can be a layer that is easily processed and resistant to etching processes that process the substrate (base material) or other layers that form the underlayer. The underlayer may be formed on the outermost surface of the substrate on which the nanoimprint process is carried out, and for example, carbon materials such as SOC (spin-on carbon), diamond-like carbon, and graphite can be used as the underlayer material. As a highly etching-resistant material, SOC, which has carbon as its main component, can be used. Similarly, SOC can be used as a highly etching-resistant material in pattern formation by nanoimprint. In this embodiment, it is preferable to carry out the nanoimprint process on an SOC layer.

[0051] The SOC preferably used as a base layer material may contain a main component (component (P)) and an organic solvent (component (Q)). The base layer material may also contain an acid generator (component (R)) and / or a crosslinking agent (component (S)), and may contain other optional components as long as they do not impair the effects of this embodiment. The following describes each component. <Ingredients (P): Main ingredient> Component (P) is the main component. Component (P) is a compound having an aromatic ring such as a benzene ring, naphthalene ring, or anthracene ring, preferably with a formula weight of 300 to 5,000, and particularly preferably with a formula weight of 500 to 2,500. A molecular weight of 300 or more is advantageous for obtaining good film-forming properties and can suppress contamination of the manufacturing equipment due to an increase in sublimation during curing. A molecular weight of 5,000 or less is advantageous for obtaining good embedding / planarization properties.

[0052] Component (P) may contain branched or cyclic saturated or unsaturated hydrocarbon groups, heteroaromatic groups, and may also contain ether groups, hydroxyl groups, ester groups, carbonyl groups, amino groups, halogen groups, sulfide groups, carboxyl groups, sulfo groups, amide groups, imide groups, cyano groups, aldehyde groups, imino groups, urea groups, carbamate groups, carbonate groups, nitro groups, and sulfonyl groups.

[0053] Specific examples of component (P) include novolac compounds such as phenol novolac, cresol novolac, and naphthol novolac, and substituted polystyrene compounds such as polyhydroxystyrene and polyhydroxyvinylnaphthalene. Component (P) may be used alone or as a mixture of two or more. <Component (Q): Solvent> Component (Q) is a solvent. Component (Q) is not particularly limited as long as it can dissolve or disperse component (P) and any optional components it may contain. Examples of component (Q) include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, nitrogen-containing solvents, etc. Component (Q) can be used alone or in combination of two or more.

[0054] Examples of alcohol-based solvents include methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, tert-butanol, n-pentanol, iso-pentanol, 2-methylbutanol, sec-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethylheptanol-4, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-teto Examples of solvents include monoalcohol-based solvents such as radicyl alcohol, sec-heptadecyl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, phenylmethylcarbinol, diacetone alcohol, and cresol; and polyhydric alcohol-based solvents such as ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, and glycerin.

[0055] Examples of ketone solvents include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-iso-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-iso-butyl ketone, trimethylnonanone, cyclohexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, diacetone alcohol, acetophenone, and phenthone.

[0056] Examples of ether-based solvents include ethyl ether, iso-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane, dimethyldioxane, 2-methoxyethanol, 2-ethoxyethanol, ethylene glycol diethyl ether, 2-n-butoxyethanol, 2-n-hexoxyethanol, 2-phenoxyethanol, 2-(2-ethylbutoxy)ethanol, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene Examples include glycol mono-n-butyl ether, diethylene glycol di-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytriglycol, tetraethylene glycol di-n-butyl ether, 1-n-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monomethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, and the like.

[0057] Examples of ester solvents include diethyl carbonate, methyl acetate, ethyl acetate, amyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, iso-propyl acetate, n-butyl acetate, iso-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate. Examples include ethyl ether, diethylene glycol acetate mono-n-butyl ether, propylene glycol acetate monomethyl ether, propylene glycol acetate monoethyl ether, propylene glycol acetate monopropyl ether, propylene glycol acetate monobutyl ether, dipropylene glycol acetate monomethyl ether, dipropylene glycol acetate monoethyl ether, glycol diacetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, iso-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, and diethyl phthalate. Examples of nitrogen-containing solvents include N-methylformamide, N,N-dimethylformamide, N,N-diethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropionamide, and N-methylpyrrolidone.

[0058] Among these, ether-based solvents and ester-based solvents are preferred, and from the viewpoint of excellent film-forming properties, ether-based solvents and ester-based solvents having a glycol structure are more preferred, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol acetate monomethyl ether, propylene glycol acetate monoethyl ether, and propylene glycol acetate monopropyl ether are even more preferred, and propylene glycol acetate monomethyl ether is particularly preferred. <Ingredient(R): Acid Generator> The underlayer material according to this embodiment may contain an acid generator as component (R). Component (R) is a component that generates acid upon the action of heat or light and promotes the crosslinking reaction of component (P) by the crosslinking agent (component (S)) described later. By containing component (R) in the curable composition underlayer forming composition, the crosslinking reaction of component (P) is promoted, and the hardness of the formed film can be further increased. Component (R) can be used alone or in combination of two or more. Examples of component (R) include onium salt compounds and N-sulfonyloxyimide compounds.

[0059] Examples of the above-mentioned onium salt compounds include sulfonium salts, tetrahydrothiophenium salts, iodonium salts, and ammonium salts. Examples of sulfonium salts include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium 2-bicyclo[2.2.1]hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, and 4-cyclohexylphenyldiphenylsulfonium trifluoromethanesulfonate.

[0060] Examples of tetrahydrothiophenium salts include 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiophenium trifluoromethanesulfonate, 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiophenium nonafluoro-n-butanesulfonate, and 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiophenium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2,2-tetrafluoroethanesulfonate.

[0061] Examples of iodonium salts include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, bis(4-t-butylphenyl)iodonium nonafluoro-n-butanesulfonate, and bis(4-t-butylphenyl)iodonium 2-bicyclo[2.2.1]hepto-2-yl-1,1,2,2-tetrafluoroethanesulfonate.

[0062] Examples of ammonium salts include triethylammonium trifluoromethanesulfonate and triethylammonium nonafluoro-n-butanesulfonate.

[0063] Examples of N-sulfonyloxyimide compounds include N-(trifluoromethanesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(nonafluoro-n-butanesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, and N-(2-bicyclo[2.2.1]hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide. Among these, onium salt compounds are preferred as component (R), iodonium salts and ammonium salts are more preferred, and bis(4-t-butylphenyl)iodonium nonafluoro-n-butanesulfonate and triethylammonium nonafluoro-n-butanesulfonate are even more preferred.

[0064] If the underlying material contains component (R), the lower limit of the content of component (R) is preferably 0.1 parts by mass, more preferably 1 part by mass, and still more preferably 3 parts by mass, per 100 parts by mass of component (P). The upper limit of the above content is preferably 15 parts by mass, more preferably 12 parts by mass, and still more preferably 10 parts by mass. By setting the content of component (R) within the above range, the crosslinking reaction of component (P) can be promoted more effectively. <Component (S): Crosslinking agent> The substrate material according to this embodiment may contain a crosslinking agent as component (S). Component (S) is a component that, upon the action of heat or acid, forms crosslinking bonds between compounds contained in component (P) in the substrate material, or forms a crosslinking structure itself. By containing component (S) in the substrate material, the hardness of the formed substrate can be increased. Component (S) can be used alone or in combination of two or more types.

[0065] Examples of component (S) include polyfunctional (meth)acrylate compounds, epoxy compounds, hydroxymethyl group-substituted phenol compounds, alkoxyalkyl group-containing phenol compounds, and compounds having alkoxyalkylated amino groups.

[0066] Examples of the above polyfunctional (meth)acrylate compounds 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, and tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate. Examples include ethylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, bis(2-hydroxyethyl) isocyanurate di(meth)acrylate, and the like.

[0067] Examples of the epoxy compounds mentioned above include novolac-type epoxy resins, bisphenol-type epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins.

[0068] Examples of the hydroxymethyl group-substituted phenol compounds mentioned above include 2-hydroxymethyl-4,6-dimethylphenol, 1,3,5-trihydroxymethylbenzene, and 3,5-dihydroxymethyl-4-methoxytoluene [2,6-bis(hydroxymethyl)-p-cresol].

[0069] Examples of the alkoxyalkyl group-containing phenol compounds mentioned above include methoxymethyl group-containing phenol compounds and ethoxymethyl group-containing phenol compounds.

[0070] Examples of compounds having the above-mentioned alkoxyalkylated amino group include (poly)methylolated melamines such as hexamethoxymethylated melamine, hexasubtoxicmethylated melamine, their alkoxy and / or hydroxy substituted derivatives, and their partial self-condensates; (poly)methylolated glycoluryls such as tetramethoxymethylated glycoluryl, tetrabutoxymethylated glycoluryl, their alkoxy and / or hydroxy substituted derivatives, and their partial self-condensates; (poly)methylolated benzoguanamines such as tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, their alkoxy and / or hydroxy substituted derivatives, and their partial self-condensates; (poly)methylolated benzoguanamines such as dimethoxymethylated dimethoxyethyleneurea, its alkoxy and / or hydroxy substituted derivatives, and their partial self-condensates; and other nitrogen-containing compounds having multiple active methylol groups in one molecule, wherein at least one hydrogen atom of the hydroxyl group of the methylol group is substituted with an alkyl group such as a methyl group or a butyl group. The compound having an alkoxyalkylated amino group may be a mixture of multiple substituted compounds, or it may contain an oligomeric component formed by partial self-condensation.

[0071] If the underlying material contains component (S), the lower limit of the component (S) content is preferably 0.1 parts by mass, more preferably 0.5 parts by mass, even more preferably 1 part by mass, and particularly preferably 3 parts by mass, per 100 parts by mass of component (P). The upper limit of the above content is preferably 50 parts by mass, more preferably 40 parts by mass, even more preferably 30 parts by mass, and particularly preferably 20 parts by mass. By setting the component (S) content within the above range, the crosslinking reaction of component (P) can be made more effective.

[0072] Other optional components include, for example, surfactants. The substrate material can be improved in terms of coatability by containing a surfactant, which in turn improves the uniformity of the coated surface of the formed substrate film and suppresses the occurrence of coating irregularities. The surfactant can be used alone or in combination of two or more types.

[0073] If the substrate material contains a surfactant, the lower limit of the surfactant content is preferably 0.01 parts by mass, more preferably 0.05 parts by mass, and even more preferably 0.1 parts by mass, per 100 parts by mass of the main component (P). The upper limit of the above content is preferably 10 parts by mass, more preferably 5 parts by mass, and even more preferably 1 part by mass. By setting the surfactant content within the above range, the coatability of the substrate material can be further improved.

[0074] Furthermore, the base layer material may be a commercially available base layer material. Examples include, but are not limited to, spin-on carbon film forming compositions such as ODL-50, ODL-69, ODL-102, ODL-180, and ODL-301 manufactured by Shin-Etsu Chemical Co., Ltd., and NFC-1400 and HM8005 manufactured by JSR. The base layer may consist of one type of composition or multiple types of compositions.

[0075] In this embodiment, a mask material may be applied as a base layer to the substrate. In current semiconductor miniaturization processes, the thinning of curable composition is progressing along with the miniaturization of processing patterns (features). Furthermore, as the aspect ratio of the processing pattern increases, a phenomenon called the microloading effect occurs, which reduces the etching rate. As a result, the etching time becomes longer, and the curable composition mask may not be able to withstand it. To pattern fine patterns with high precision at a high aspect ratio, methods such as multilayer curable composition processes and inversion processes may be used. In these methods, the curable composition pattern is first transferred to a layer with high etching resistance (high etching resistance layer) separate from the curable composition, and then the target base layer is processed using the high etching resistance layer as an etching mask.

[0076] If the ratio of carbon atoms to the total number of atoms excluding hydrogen in the substrate after baking is 80% or more, the curable compositions (A1) and (A2) can adhere firmly to the substrate after curing by light irradiation. The ratio of carbon atoms in the substrate is preferably 80% or more, and more preferably 80-95%.

[0077] The precursor composition of the underlayer can be a carbon-based material, such as a mixture of a naphthalene compound and a solvent, and can be applied to the substrate by spin coating. Typically, the precursor composition of the underlayer can be applied to a thickness of 0.1 nm to 1000 nm after baking. It is preferable to apply a sufficient amount of composition to achieve uniform flatness on the substrate surface. By baking the substrate after application, the solvent components volatilize, and further carbonization can occur, resulting in a carbon film with a carbon atom ratio of 80% or more. The baking conditions are adjusted as appropriate depending on the type of composition used, but generally, it is preferable to bake at approximately 200°C to approximately 350°C for approximately 30 seconds to 90 seconds, and particularly preferable to bake at approximately 220°C to approximately 300°C for approximately 45 seconds to 60 seconds.

[0078] The requirements for the diffusion coefficient and solubility coefficient of the atmospheric gas relative to the underlying layer will be described later. [Pattern formation method] Next, the pattern formation method according to the first embodiment will be described using the schematic cross-sectional view in Figure 1. The cured film formed by this embodiment is preferably a film having a pattern of size 1 nm to 10 mm, and more preferably a film having a pattern of size 10 nm to 100 μm. Generally, the pattern formation technique that uses light to produce a film having a nano-sized pattern (uneven structure) of 1 nm to 100 nm is called optical nanoimprint spectroscopy. The film formation method according to this embodiment can utilize optical nanoimprint spectroscopy, but the curable composition may be cured by other energy (e.g., heat, electromagnetic waves). The film formation method of this embodiment may be implemented as a method for forming a film having a pattern (pattern formation method), or as a method for forming a film without a pattern (e.g., a planarized film). First, an example in which the film formation method of this embodiment is applied to forming a film having a pattern will be described. A film formation method may include, for example, a formation step of forming a base layer, a placement step of placing a hardening organism on the base layer, a contact step of bringing a hardening composition into contact with a mold, a hardening step of hardening the hardening composition, and a separation step of separating the hardening composition from the mold. The placement step is performed after the formation step, the contact step is performed after the placement step, the hardening step is performed after the contact step, and the separation step is performed after the hardening step. <Formation process [1]> In the formation process, as schematically shown in [1] of Figure 1, a base layer 102 is formed on the surface of the substrate (base material) 101 (or the surface of the workpiece layer if the substrate 101 has a workpiece layer). Here, a structure having a substrate (base material) 101 and a base layer 102 placed on the substrate 101 can also be called a substrate. The base layer 102 can be formed, for example, by laminating or coating the material of the base layer 102 onto the substrate 101 and then performing a bake process on the substrate 101 to which the material has been coated. Examples of methods for forming the base layer 102 include the inkjet method, dip coat method, air knife coat method, curtain coat method, wire bar coat method, gravure coat method, extrusion coat method, spin coat method, slit scan method, etc. Among these methods, the spin coat method is particularly preferred. When forming the base layer 102 using the spin coat method, a bake process may be performed as needed to volatilize the solvent components. The bake conditions can be, for example, about 200°C to about 350°C for about 30 seconds to about 90 seconds. The bake conditions are appropriately adjusted depending on the type of composition used.

[0079] The average film thickness of the underlayer 102 can be determined according to the application, but for example, it is 0.1 nm to 10,000 nm, preferably 1 nm to 250 nm, and particularly preferably 5 nm to 50 nm.

[0080] Alternatively, a multilayer film may be used as the base layer 102, in which a spin-on-glass (SOG) film or silicon oxide film with a thickness of 0.1 nm to 250 nm is further laminated on top of the SOC. <Placement process [2-1], [2-2]> In the placement step, the curable composition may be placed on the underlayer 102 on the substrate (base material) 101, as schematically shown in [2-1] and [2-2] of Figure 1. The placement step may include, for example, a first placement step of placing the curable composition (A1) 103 on the underlayer 102, and a second placement step of discretely dropping droplets of curable composition (A2) 104 onto the curable composition (A1) 103. The curable composition (A1) and its placement step may be omitted.

[0081] Prior to the placement step, the surface of the underlayer 102 may have its adhesion to the curable composition (A1) and / or curable composition (A2) improved by surface treatment such as silane coupling treatment, silazane treatment, or deposition of an organic thin film. (First placement step [2-1]) In the first placement step, the curable composition (A1) 103 can be placed on the substrate layer 102, as schematically shown in [2-1] of Figure 1. For example, the curable composition (A1) 103 is laminated or coated on the substrate layer 102, thereby forming a coating film. In this embodiment, methods for placing the curable composition (A1) 103 include, for example, inkjet coating, dip coating, air knife coating, curtain coating, wire bar coating, gravure coating, extrusion coating, spin coating, slit scanning, etc. Among these methods, the spin coating method is particularly preferred. When the curable composition (A1) 103 is applied using the spin coating method, a baking step may be performed as needed to volatilize the solvent component (d).

[0082] The average film thickness of the curable composition (A1) 103 can be determined according to the application, but for example, it is 0.1 nm to 10,000 nm, preferably 1 nm to 20 nm, and particularly preferably 1 nm to 10 nm. The curable composition (A1) and its arrangement step may be omitted. A schematic cross-sectional view when the curable composition (A1) and its arrangement step are omitted is shown in Figure 2.

[0083] (Second placement process [2-2]) In the second placement step, droplets of curable composition (A2) 104 can be discretely dropped onto curable composition (A1) 103, as schematically shown in [2-2] of Figure 1. An inkjet method is particularly preferred as the placement method. It is preferable that the droplets of curable composition (A2) 104 be densely placed on the region of the substrate 101 opposite to the region where the recesses constituting the pattern of the mold 106 are densely present, and sparsely placed on the region of the substrate 101 opposite to the region where the recesses are sparsely present. This allows the residual film 109, described later, to be controlled to have a uniform thickness regardless of the density of the pattern of the mold 106.

[0084] In the second placement step, when curable composition (A1) 103 is also placed, the droplets of curable composition (A2) 104 spread rapidly (press spread) as indicated by arrow 105, due to the Marangoni effect driven by the difference in surface energy (surface tension), as described above. If curable composition (A1) is substantially photoreactive, as a result of mixing curable composition (A1) and curable composition (A2), the photopolymerization initiator, which is component (b) of curable composition (A2), also migrates to curable composition (A1), thereby allowing curable composition (A1) to acquire photosensitivity. <Contact process [3]> In the contact step, the curable composition and the mold 106 are brought into contact, as schematically shown in [3] of Figure 1. The contact step includes a step of changing the state from one in which the curable composition and the mold 106 are not in contact to a state in which they are in contact, and a step of maintaining the state in which they are in contact. In one example, the mold 106 having the pattern to be transferred can be brought into contact with a liquid obtained by mixing curable composition (A1) and curable composition (A2). As a result, the liquid obtained by partially mixing curable composition (A1) and curable composition (A2) fills the recesses of the fine pattern on the surface of the mold 106, and the liquid becomes a liquid film that fills the fine pattern of the mold.

[0085] If the next curing step includes a light irradiation step, the mold 106 may be made of a light-transmitting material, taking this into consideration. Specifically, preferred materials for the mold 106 include light-transmitting resins such as glass, quartz, PMMA, and polycarbonate resin, transparent metal vapor-deposited films, flexible films such as polydimethylsiloxane, photocurable films, and metal films. However, if a light-transmitting resin is used as the material for the mold 106, a resin that does not dissolve in the components contained in the curable composition may be selected. Quartz is particularly preferred as the material for the mold 106 because it has a low coefficient of thermal expansion and low pattern distortion.

[0086] The fine pattern on the surface of mold 106 may have a height of, for example, 4 nm to 200 nm. The lower the height of the pattern, the lower the force required to separate mold 106 from the cured film of the curable composition during the separation process, i.e., the release force. Also, the number of release defects remaining on the mold 106 side due to the pattern of the curable composition being torn off during the separation process will decrease. The impact when separating the mold may cause elastic deformation of the pattern of the curable composition, causing adjacent pattern elements to come into contact with each other, resulting in adhesion or breakage. However, it is advantageous to have a pattern element height that is approximately twice the width of the pattern element (aspect ratio of 2 or less) in order to avoid these problems. On the other hand, if the height of the pattern element is too low, the processing accuracy of the substrate 101 may be reduced.

[0087] The mold 106 may be surface-treated before the contact process to improve the release properties from the curable compositions (A1) and (A2) to the surface of the mold 106. One method of surface treatment is to apply a release agent to the surface of the mold 106 to form a release agent layer. Examples of release agents to be applied to the surface of the mold 106 include silicone-based release agents, fluorine-based release agents, hydrocarbon-based release agents, polyethylene-based release agents, polypropylene-based release agents, paraffin-based release agents, montan-based release agents, and carnauba-based release agents. For example, commercially available coating-type release agents such as Optool® DSX manufactured by Daikin Industries, Ltd. can also be suitably used. One type of release agent may be used alone, or two or more types may be used in combination. Among these, fluorine-based and hydrocarbon-based release agents are particularly preferred.

[0088] In the contact process, when the mold 106 is brought into contact with the curable compositions (A1) and (A2), the pressure applied to the curable compositions (A1) and (A2) is not particularly limited. The pressure may be, for example, 0 MPa or more and 100 MPa or less. Furthermore, the pressure is preferably 0 MPa or more and 50 MPa or less, more preferably 0 MPa or more and 30 MPa or less, and even more preferably 0 MPa or more and 20 MPa or less.

[0089] If the press-spreading of droplets of curable composition (A2) 104 is progressing in the second placement step ([2-2]), the spread of curable composition (A2) 104 in the contact step can be completed quickly. If the spread and fill of curable compositions (A1) and (A2) are completed quickly in the contact step, the time for which the mold 106 is in contact with curable compositions (A1) and (A2) (this is called the contact step time) can be set to be shorter. Shortening the contact step time reduces the time required for pattern formation (film formation), which leads to improved productivity. The contact step time is preferably 0.1 seconds or more and 3 seconds or less, and particularly preferably 0.1 seconds or more and 1 second or less. If the contact step time is shorter than 0.1 seconds, the spread and fill will be insufficient, and defects called unfilled defects tend to occur frequently.

[0090] The contacting step can be carried out under the condition that, for example, there is a gas (hereinafter referred to as the gas in the gap) in the space between the underlying layer 102 and the mold 106, and the solubility coefficient of the gas in the gap with respect to the underlying layer 102 is 0.5 kg / m 3 ·atm or more and 10 kg / m 3 ·atm or less. Here, if the solubility coefficient is greater than 10 kg / m 3 ·atm, a large amount of the gas in the gap dissolves, so there is a possibility that the dry etching resistance and / or mechanical strength of the underlying layer 102 may be reduced. If the solubility coefficient is less than 0.5 kg / m 3 ·atm, the effects aimed at by the present invention cannot be sufficiently obtained. Also, when the solubility coefficient of the gas in the gap with respect to the underlying layer layer 102 is S [kg / m 3 ·atm] and the diffusion coefficient of the gas in the gap in the underlying layer 102 is D [m 2 / s], the product (S·D) of S and D is preferably 0.5×10 -10 or more and 10×10 -10 or less. Here, if S·D is greater than 10×10 -10 a large amount of the gas in the gap dissolves, so there is a possibility that the dry etching resistance and / or mechanical strength of the underlying layer 102 may be reduced. If S·D is less than 0.5×10 -10 the effects aimed at by the present invention cannot be sufficiently obtained. Further, if 1% by weight or more of the gas in the gap dissolves in the curable composition, the dry etching resistance and / or mechanical strength of the cured film may be reduced. Therefore, the solubility of the gas in the gap in the curable composition at 1 atmospheric pressure is preferably 10 kg / m 3 or less.

[0091] Specific examples of gases in the gap include, for example, carbon dioxide, methane, various fluorocarbon gases, or mixtures of two or more of these gases. These mixtures of carbon dioxide, methane, various fluorocarbon gases, or mixtures of two or more of these gases can also be used in combination with gases that do not have high solubility coefficients, such as nitrogen, oxygen, helium, or argon. When using a mixture of gases, the diffusion coefficient and solubility coefficient of the mixture can be calculated as a weighted average value according to the molar ratio of each gas. The contact process can be carried out, for example, under a pressure of 0.0001 atmospheres to 10 atmospheres. <Curing process [4]> In the curing process, as shown in [4] of Figure 1, a cured film is formed by curing the curable composition by irradiating it with light as curing energy. In the curing process, for example, light may be irradiated through the mold 106 to a layer formed by partially mixing curable composition (A1) 103 and curable composition (A2) 104. More specifically, light may be irradiated through the mold 106 to the curable composition (A1) and / or (A2) filled in the fine pattern of the mold 106. As a result, the curable composition (A1) and / or (A2) filled in the fine pattern of the mold 106 hardens to form a cured film 108 having a pattern.

[0092] Here, the light 107 to be irradiated can be selected according to the sensitivity wavelength of the curable compositions (A1) and (A2). Specifically, the light 107 can be appropriately selected from ultraviolet light, X-rays, or electron beams with a wavelength of 150 nm to 400 nm. Among these, ultraviolet light is particularly preferred for light 107. This is because many commercially available curing aids (photopolymerization initiators) are compounds that are sensitive to ultraviolet light. Examples of light sources that emit ultraviolet light include high-pressure mercury lamps, ultra-high-pressure mercury lamps, low-pressure mercury lamps, deep-UV lamps, carbon arc lamps, chemical lamps, metal halide lamps, xenon lamps, KrF excimer lasers, ArF excimer lasers, F2 excimer lasers, etc., but ultra-high-pressure mercury lamps are particularly preferred. The number of light sources used may be one or more. Furthermore, the light irradiation may be performed over the entire area of ​​the curable composition (A1) and / or (A2) filled in the fine pattern of the mold, or it may be limited to only a portion of the area. Also, the light irradiation may be performed intermittently over the entire area of ​​the substrate multiple times, or it may be performed continuously over the entire area. Moreover, in the first irradiation process, a first area may be irradiated with light, and in the second irradiation process, a second area different from the first area may be irradiated with light.

[0093] In the curing process, as mentioned above, light leakage, that is, the diffusion of light outside the shot area, may occur due to cost constraints of the mold and equipment. In this embodiment, if the curable composition (A1) is substantially photoreactive, the curable composition (A1) will not cure by light irradiation alone. Therefore, the curable composition (A1) on adjacent shot areas will not cure due to light leakage generated from the shot area. As a result, even in adjacent shot areas, a pattern with few unfilled defects can be formed over the entire area with a short filling time. On the other hand, in the shot area, as mentioned above, as a result of mixing the curable composition (A1) and the curable composition (A2), the photoinitiator (b2) component of the curable composition (A2) also migrates to the curable composition (A1). As a result, the curable composition (A1) becomes photosensitive, and both the curable composition (A1) and (A2) cure with the irradiated light to become a cured film 108 having a pattern. <Separation process [5]> In the separation process, the cured film 108 and the mold 106 are separated, as schematically shown in [5] in Figure 1. For example, by separating the patterned cured film 108 from the mold 106, a cured film 108 with a pattern that is the reverse of the fine pattern of the mold 106 is obtained in an upright state. Here, some of the cured film remains in the recesses of the patterned cured film 108. This film may be called residual film 109.

[0094] If a condensable gas is used as the gap gas in the contact step [3], the condensable gas may vaporize as the pressure at the interface between the cured film 108 and the mold 106 decreases when the cured film 108 and the mold 106 are separated in the separation step. This can reduce the force required to separate the cured film 108 and the mold 106.

[0095] The method for separating the patterned cured film 108 from the mold 106 is not limited to any particular conditions, as long as no part of the patterned cured film 108 is physically damaged during separation. For example, the substrate 101 may be fixed and the mold 106 may be moved away from the substrate 101. Alternatively, the mold 106 may be fixed and the substrate 101 may be moved away from the mold 106. Or, both may be pulled in opposite directions to separate them.

[0096] By a series of steps (manufacturing process) having the above steps [2-1] to [5], preferably steps [1] to [5] in this order, a cured film having a desired uneven pattern shape (a pattern shape due to the uneven shape of the mold 106) at a desired position can be obtained.

[0097] In the film formation method or pattern formation method of this embodiment, the curable composition (A1) is laminated collectively over most of the substrate surface in step [2-1], and the repeating unit (shot) consisting of steps [2-2] to [5] can be repeated multiple times on the same substrate. Alternatively, steps [2-1] to [5] may be repeated multiple times on the same substrate. By repeating the repeating unit (shot) consisting of steps [2-1] to [5] or steps [2-2] to [5] multiple times, a cured film 108 having multiple desired patterns at desired positions on the substrate can be obtained.

[0098] The following describes an example in which the film-forming method of this embodiment is applied to a method for forming a film without a pattern (for example, a planar film). The film-forming method may include, for example, a forming step of forming a base layer, a placement step of placing a curable composition on the base layer, a contact step of bringing the curable composition into contact with a mold, a curing step of curing the curable composition, and a separation step of separating the curable composition from the mold. Here, a mold having a flat surface is used as the mold, and a cured film having a surface following the flat surface can be formed through the contact step, curing step and separation step. The placement step is performed after the forming step, the contact step is performed after the placement step, the curing step is performed after the contact step, and the separation step is performed after the curing step. ≪Manufacturing Methods for Circuit Boards, Electronic Components, and Optical Instruments≫ Using a cured film 108 having a pattern formed according to the first embodiment as a mask, the substrate 101 (or the layer to be processed if the substrate 101 has a layer to be processed) can be processed using a processing method such as etching. Alternatively, the layer to be processed may be deposited on the cured film 108 having a pattern, and then the pattern transfer may be performed using a processing method such as etching. In this way, a fine structure such as a circuit structure can be formed on the substrate 101 using the cured film 108 having a pattern. This makes it possible to manufacture devices such as semiconductor devices. Furthermore, it is also possible to form electronic devices including such devices, such as displays, cameras, and medical devices. Examples of devices include LSIs, system LSIs, DRAMs, SDRAMs, RDRAMs, D-RDRAMs, and NAND flash memory.

[0099] It is also possible to obtain an optical component that utilizes a cured film 108 having a pattern formed according to the first embodiment as an optical component such as a diffraction grating or a polarizing plate (including when it is used as a part of an optical component). In such a case, the optical component can have at least a substrate 101 and a cured film 108 having a pattern on the substrate 101.

[0100] Furthermore, by performing known photolithography processes such as nanoimprint lithography (NIL) or extreme ultraviolet exposure (EUV) on a film without a pattern formed according to the first embodiment (for example, a planarized film), devices such as semiconductor devices can be manufactured. ≪Second Embodiment≫ The film-forming method of the second embodiment may be implemented as a method for forming a film without a pattern (e.g., a planar film), or as a method for forming a film with a pattern (a pattern-forming method). First, an example in which the film-forming method of the third embodiment is applied to forming a film without a pattern will be described. The film-forming method may include, for example, a formation step of forming a base layer, a placement step of placing a curable organism on the base layer, a contact step of bringing a curable composition into contact with a mold, a curing step of curing the curable composition, and a separation step of separating the curable composition from the mold. The placement step is performed after the formation step, the contact step is performed after the placement step, the curing step is performed after the contact step, and the separation step is performed after the curing step. In the contact step, as schematically shown in Figure 3, a mold 18 having a flat surface is used as the contact surface with the curable composition.

[0101] The mold 18 has a surface (contact surface) that comes into contact with the curable composition, and this surface may be made of an organic material. The mold 18 may have a base material 220 and a protective layer 210 that covers the base material 220. The base material 220 of the mold 18 may be made of, for example, a glass-based material, silicon, spinite, fused silica, synthetic silica, silicon, organic polymer, siloxane polymer, fluorocarbon polymer, metal, cured sapphire, other similar materials, or a combination of two or more of these materials. Glass-based materials may include, for example, soda-lime glass, borosilicate glass, alkali-barium silicate glass, aluminosilicate glass, synthetic silica, or fused silica. For example, if the base material 220 of the mold 18 is made of an organic material such as an organic polymer, siloxane polymer, or fluorocarbon polymer and has a thickness of 2 μm or more, the protective layer 210 may be omitted.

[0102] The protective layer 210 may have a multilayer structure. Furthermore, the protective layer 210 constituting the surface of the mold 18 may be composed of organic materials. The outermost surface of the protective layer 210 is preferably a fluororesin. The protective layer 210 may be composed of, for example, a hydrocarbon polymer or a fluororesin. Examples of hydrocarbon polymers include acrylic resins such as polytrimethylsilylpropyne (PTMSP) and polymethyl methacrylate (PMMA), polycarbonate polymers, polyimides, polyethylene, and polypropylene. Examples of fluororesins include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), perfluoroalkoxyalkane (PFA), perfluoroethylenepropene copolymer (FEP), and amorphous fluoropolymer. Amorphous fluoropolymers may include perfluorodioxoletetrafluoroethylene copolymer. Furthermore, amorphous fluoropolymers may include chemical structures containing -(CXY-CF2-)a-(-Z-)b-, where X and Y may be F, Cl, or H. Z may be a fluorocarbon ring structure of a 4-membered, 5-membered, or 6-membered ring containing at least one COC bond. Alternatively, amorphous fluoropolymers may include the following: For example, copolymers of bistrifluoromethyl-4,5-difluoro-1,3-dioxol (PDD) (shown in formula 1, for example). Furthermore, amorphous fluoropolymers may include chemical structures containing -(CF2-Z-CF2-), where X and Y may be F, Cl, or H. Z may be a fluorocarbon ring structure of a 4-membered, 5-membered, or 6-membered ring containing at least one COC bond, as shown in formula 2. Examples of commercially available fluoropolymers include Teflon (a registered trademark of DuPont) and Cytop (AGC).

[0103] The difference in height of the surface irregularities of the mold 18 is preferably 4 nm or less. After the contact step in which the mold 18 is brought into contact with the curable organism, a curing step [4] and a separation step [5] are performed to form a cured film having a surface that conforms to the flat surface of the mold 18.

[0104] In the contact process, for example, a gas (hereinafter referred to as gap gas) is present in the space between the substrate 200 and the mold 18, and the solubility coefficient of the gap gas for the organic material or protective layer 210 constituting the surface of the mold 18 is 0.5 kg / m³. 3 ·ATM or more 10kg / m 3 This can be done under the condition that the pressure is less than or equal to atm. Here, 10 kg / m 3 If the value is greater than atm, the protective layer 210 may detach from the substrate 220 due to expansion. Also, the solubility coefficient of the gas in the gap for the organic material constituting the surface of the mold 18 or the protective layer 210 should be S [kg / m 3 ·atm], the diffusion coefficient of the gas in the gap in the organic material or protective layer 210 constituting the surface of the mold 18 is D[m 2 When [s] is given, the product of S and D (S·D) is 0.5 × 10 -10 The above 10 x 10 -10 The following is preferable: where S·D is 10 × 10 -10 If the solubility is greater than this, the protective layer 210 may peel off from the substrate 220 due to the expansion of the protective layer 220. Furthermore, if 1% or more of gap gas dissolves in the curable composition, the dry etching resistance and / or mechanical strength of the cured film will be reduced, so the solubility of gap gas in the curable composition at 1 atmosphere should be 10 kg / m³. 3 The following is preferable:

[0105] Specific examples of gases in the gap include, for example, carbon dioxide, methane, various fluorocarbon gases, or mixtures of two or more of these gases. These mixtures of carbon dioxide, methane, various fluorocarbon gases, or mixtures of two or more of these gases can also be used in combination with gases that do not have high solubility coefficients, such as nitrogen, oxygen, helium, and argon. When using a mixed gas, the diffusion coefficient and solubility coefficient of the mixed gas can be calculated as a weighted average value according to the molar ratio of each gas. The contact process can be carried out, for example, under a pressure of 0.0001 atmospheres to 10 atmospheres.

[0106]

number

[0107]

number

[0108] Known photolithography processes such as nanoimprint lithography (NIL) and extreme ultraviolet exposure (EUV) can be performed on the flat cured film obtained by the above film formation method. Alternatively, a spin-on-glass (SOG) film and / or silicon oxide layer can be laminated, and a curable composition can be applied thereon for photolithography. This makes it possible to manufacture devices such as semiconductor devices. Furthermore, it is possible to form electronic devices including such devices, such as displays, cameras, and medical devices. Examples of devices include LSIs, system LSIs, DRAMs, SDRAMs, RDRAMs, D-RDRAMs, and NAND flash memory.

[0109] The following describes an example in which the film-forming method of the second embodiment is applied to a method for forming a film having a pattern (pattern-forming method). The film-forming method may include, for example, a forming step of forming a base layer, a placement step of placing a curable organism on the base layer, a contact step of bringing a curable composition into contact with a mold, a curing step of curing the curable composition, and a separation step of separating the curable composition from the mold. Here, the mold has a pattern, and a film on which the pattern is transferred can be formed through the contact step, the curing step, and the separation step. The placement step is performed after the forming step, the contact step is performed after the placement step, the curing step is performed after the contact step, and the separation step is performed after the curing step. [Examples]

[0110] To supplement the above embodiments, more specific examples will be described below. <Calculation of filling time in pattern formation> The time from when the mold comes into contact with droplets of liquid curable composition (A2) dropped in a square arrangement onto the substrate, until adjacent droplets collide and form bubbles, and then until the resulting bubbles dissolve into the curable composition (A2), the mold, and the substrate and completely disappear, was theoretically calculated as follows. This time is the filling time.

[0111] The filling time is the sum of the dynamic spread time and the static spread time. The dynamic spread time is the time from when the mold comes into contact with the curable composition until adjacent droplets come into contact with each other, trapping gas (gas in the gap) at the three-phase interface of the mold, substrate, and droplets, and forming bubbles. The static spread time is the time until the formed bubbles dissolve into the curable composition (A2), mold, and substrate and completely disappear.

[0112] The dynamic spread time was calculated by coupling the lubrication equation for droplets of the cylindrical curable composition (A2) with the motion equation of the mold. The reason for adopting the lubrication equation is that the spacing between the applied droplets is about 100 μm, and the height of the droplet distribution is on the order of a few nanometers to a few micrometers, resulting in a high aspect ratio, so the pressure change in the height direction can be ignored. Also, the Reynolds number can be considered sufficiently small, so it was treated as an incompressible fluid. An analytical solution exists for the above coupled equation, and the dynamic spread time T DS teeth,

[0113]

number

[0114] This is the result. Here, V is the volume of one droplet, R is half the distance between droplets, R0 is the radius of the cylinder of the droplet of curable composition (A2), μ is the viscosity of curable composition (A2), σ is the surface tension, θ u The contact angle between the curable composition (A2) and the mold, θ d This is the contact angle between the curable composition and the substrate.

[0115] Next, the time T required for static spread. SS The calculation method is shown below. As shown in Figure 4, at the moment when droplets of the curable composition (A2) collide, the bubbles shown in white have the same volume at a radius r. g It is approximated by a cylinder of radius r, and the calculation domain also has the same volume. c It is approximated by a cylinder. Under these initial conditions, the ideal gas law, the equation for gas mass, the diffusion equation of the gas into the mold, the diffusion equation of the gas into the underlying layer, the diffusion equation of the gas into the curable composition (A2), the equation representing the conservation of mass of the curable composition (A2), the lubrication equation for the curable composition region, and the equation of motion for the mold are coupled to obtain the bubble volume and pressure p g Then, the time evolution equation for the mold height h is obtained. The equation for an ideal gas is given as follows:

[0116]

number

[0117] Here, p g ρ is the pressure of the gas. g Here, R is the density of the gas, R is the gas constant, and T is the temperature. The equation for the mass of the gas is given below.

[0118]

number

[0119] Here, M g is the mass of the gas.

[0120] The diffusion equation for the diffusion of gas into the mold or substrate is given below.

[0121]

number

[0122] Here, C g D is the gas concentration in the mold. g is the diffusion coefficient of the gas into the mold or substrate. The boundary conditions were that dissolution according to Henry's Law occurs only at the surface where the mold or substrate is in contact with the bubbles, and that no exchange of materials occurs at the surface in contact with the curable composition (A2).

[0123] The diffusion equation for gas diffusion into the curable composition (A2) is the same as the diffusion equation for gas diffusion into the mold or substrate. However, the boundary conditions are as follows: dissolution according to Henry's Law occurs only at the surface where the curable composition (A2) is in contact with the bubbles, and no exchange of mass occurs at the surface in contact with the mold or the cylindrical side of the calculation domain. The equation for the conservation of mass of the curable composition (A2) is given below.

[0124]

number

[0125] Here ,ρ I The density of the curable composition (A2) is V d The volume of the droplet of the curable composition (A2) is M. r is the total mass of the curable composition (A2). The lubrication equation for the region of the curable composition (A2) is given as follows:

[0126]

number

[0127] Here, μ is the viscosity of the curable composition (A2) as described above. The equation of motion for the mold is given below.

[0128]

number

[0129] With the target film thickness RLT as the thickness h of the curable composition (A2),

[0130]

number

[0131] This condition was used as the termination criterion in the Static Spread calculation.

[0132] Furthermore, when there is no underlayer and droplets of the curable composition (A2) are placed directly on the silicon substrate, the solubility and diffusion coefficient in the underlayer were assumed to be 0 for calculation purposes. <Calculation of filling time in flattening> In the case of flattening, the organic material or protective layer constituting the surface of the mold was considered to play the same role as the underlayer in the calculation of the filling time for pattern formation. <Calculation of the diffusion coefficient of gas in a curable composition> In this example, the diffusion coefficient of the gas in the curable composition (A2) was calculated using molecular dynamics calculations for a molecular assembly containing 10 gas molecules for every 500 molecules constituting the composition. In this example, molecular dynamics calculations were performed using GROMACS-2016.4 (Copyright (c) 2001-2017, The GROMACS development team at Uppsala University, Stockholm University and the Royal Institute of Technology, Sweden). The molecular dynamics calculation method is described in Non-Patent Literature 3.

[0133] In molecular dynamics calculations, the sampling of equilibrium states was obtained by placing the target molecules within a unit cell subject to periodic boundary conditions, calculating the forces acting between atoms in each molecule for each time step, and then calculating the trajectory of all atoms as it evolves over time.

[0134] To perform molecular dynamics calculations, it is necessary to pre-set parameters called force field parameters, which define the interactions between atoms. The method for setting these parameters will be described later. Molecular dynamics calculations consist of three stages: compression, relaxation, equilibrium, and production run. The compression stage is performed to form an appropriate molecular assembly, the equilibrium stage is performed to guide the calculation system to a thermodynamic equilibrium state, and the production run is performed to sample the equilibrium state. The calculation conditions used for the compression stage are a simulation time of 40 ps, ​​a temperature of 700 K, a compressibility setting of 0.000045, and a pressure setting of 10000 atm, and it is a constant temperature and constant pressure simulation using the Berendsen method. The calculation conditions used for the equilibrium stage are a simulation time of 5 ns, a temperature of 300 K, a compressibility setting of 0.000045, and a pressure setting of 1 atm, and it is a constant temperature and constant pressure simulation using the Berendsen method. The calculation conditions used for the Production Run are a simulation time of 20 ns, a temperature of 300 K, a compressibility setting of 0.000045, and a pressure setting of 1 atm. This is a constant temperature and constant pressure simulation using the Berendsen method.

[0135] The diffusion coefficient was calculated from the mean square displacement of the gas molecules based on the molecular motion history obtained by the aforementioned Production Run.

[0136] The force field parameters consist of two types: electrostatic force field parameters and non-electrostatic force field parameters. For the electrostatic force field parameters, we used the assigned charges to each atom, obtained by performing charge fitting on the electrostatic potential calculated using the Kohn-Sham method (exchange-correlation functional: B3LYP), a quantum chemical calculation technique, with basis sets 6-31g*), using points based on the MERZ-Singh-Killmans scheme.In the case of a high-frequency design, the Gaussian waveform Gaussian09(Gaus sian09,RevisionC.01,MJFrisch,GWTrucks,HBSchlegel,G EScuseria, MARobb,JRCheeseman,G.Scalmani,V.Barone,B.Mennucci,GAPetersson,H.Nakatsuji,M.Caricato,X.Li ,HPHratchian,AFIzmaylov,J.Bloino,G.Zheng,JLSonnenberg,M.Hada,M.Ehara,K.Toyota,R.Fukuda,J.Hasegawa,M .Ishida,T.Nakajima,Y.Honda,O.Kitao,H.Nakai,T.Vreven,JAMontgomery,Jr.,JEPeralta,F.Ogliaro,M.Bearpark, JJHeyd,E.Brothers,KNKudin,VNStaroverov,T.Keith,R.Kobayashi,J.Normand,K.Raghavachari,A.Rendell,JCBur ant,SSIyengar,J.Tomasi,M.Cossi,N.Rega,JMMillam,M.Klene,JEKnox,JBCross,V.Bakken,C.Adamo,J.Jaramillo,R .Gomperts,REStratmann,O.Yazyev,AJAustin,R.Cammi,C.Pomelli,JWOchterski,RLMartin,K.Morokuma,VGZakrzew ski,GAVoth,P.Salvador,JJDannenberg,S.Dapprich,ADDaniels,O.Farkas,JBForesman,JVOrtiz,JCioslowski,and DJFox,Gaussian,Inc.,Wallingford CT,2010.) Merz-Singh-Ki On the llmans scale, it is rated 4 and 5 in the various ranges. As a non-electrostatic force field parameter, we used the general amber force field (GAFF), which is commonly used for organic molecules. <Experimental Method for Measuring Filling Time in Pattern Forming Methods> A curable composition (A2-1) was prepared consisting of 9.0 parts by weight of isobornyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: IB-XA), 38 parts by weight of benzyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name: V#160), 47 parts by weight of neopentyl glycol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: NP-A), and 3 parts by weight of Lucirin TPO (manufactured by BASF).

[0137] 3.25 pL droplets of the curable composition (A2-1) were uniformly dropped in a square arrangement of 140 μm sides onto a 26 × 33 mm area of ​​a silicon substrate or a silicon substrate coated with a 200 nm thick underlayer, and a quartz blank mold (hereinafter referred to as "mold") was brought into contact with the surface. ODL-301 manufactured by Shin-Etsu Chemical Co., Ltd. was used as the base layer material.

[0138] Using a 5x magnification optical microscope, the spreading behavior of droplets of the curable composition (A2-1) was observed through the mold, specifically the shrinkage and disappearance behavior of bubbles trapped at the three-phase interface between the mold, substrate, and curable composition (A2-1). The time until disappearance was measured, and the time from contact between the curable composition and the mold until the bubbles disappeared was measured as the filling time.

[0139] In a helium atmosphere (gas in the gap = helium), the filling time was 2.7 seconds when the underlying layer thickness was zero nm, and 0.7 seconds when it was 200 nm thick. In an air atmosphere (gas in the gap = air), the bubbles did not disappear even after 24 seconds when the underlying layer thickness was zero nm, and 0.6 seconds when it was 200 nm thick. In a carbon dioxide atmosphere (gas in the gap = carbon dioxide), the filling time was 2.67 times longer than in a helium atmosphere when the underlying layer thickness was zero. <Liquid properties of curable compositions used in pattern formation methods> To perform theoretical calculations of the filling time, the viscosity, surface tension, contact angle with the substrate, and contact angle with the mold of the curable composition (A2-1) were measured, and the results are shown in Table 1.

[0140] [Table 1]

[0141] <Liquid properties of the curable composition used in the planarization method> In this embodiment, various calculations were performed on a model curable composition (A2-2) having the viscosity, surface tension, and contact angle with the organic material or protective layer constituting the surface of the substrate and mold as shown in Table 2.

[0142] [Table 2]

[0143] <Example of theoretical calculation of filling time for pattern formation> Table 3 summarizes the diffusion coefficients and solubility coefficients of the hardening composition (A2), the substrate, and the gases (helium, nitrogen, oxygen, carbon dioxide) in the mold, which are necessary for the theoretical calculation of filling time.

[0144] [Table 3]

[0145] The basis for the physical properties listed in Table 2 is explained below.

[0146] The solubility and diffusion coefficients of helium, nitrogen, oxygen, and carbon dioxide in silicon substrates were all assumed to be zero. This is based on the known fact that gases hardly permeate through silicon crystals.

[0147] The helium diffusion coefficient in the mold and the helium solubility coefficient in the mold were based on known values.

[0148] For carbon dioxide, nitrogen, and oxygen, the solubility coefficients and diffusion coefficients in the mold were both assumed to be zero. This is based on the known fact that carbon dioxide, nitrogen, and oxygen hardly permeate the mold compared to helium.

[0149] The solubility coefficients of helium, nitrogen, oxygen, and carbon dioxide in the curable composition (A2), and the helium, nitrogen, oxygen, and carbon dioxide in the curable composition, were determined using the molecular dynamics calculations described above, with the diffusion coefficient of isobornyl acrylate, one of the components of the curable composition (A2-1), being used.

[0150] The solubility coefficient of helium in the curable composition (A2) was chosen to be such that the calculated filling time without a substrate matched the measured filling time without a substrate, as shown in Comparative Example 1 in Table 4 below. For the solubility coefficients of nitrogen and oxygen in the curable composition (A2), as shown in Comparative Example 2 of Table 4 below, the calculated filling time when there is no substrate was adopted to match the measured filling time when there is no substrate.

[0151] The solubility coefficient of carbon dioxide in the curable composition (A2) was determined using a value that matched the calculated filling time in the absence of a substrate, as shown in Comparative Example 3 of Table 4 below.

[0152] For the solubility coefficient of helium in the substrate and the diffusion coefficient of helium in the substrate, as shown in Comparative Example 4 of Table 5 below, the calculated filling time when the substrate was 200 nm thick was adopted if it matched the measured filling time when the substrate was 200 nm thick.

[0153] The diffusion coefficients of nitrogen, oxygen, and carbon dioxide in the underlying layers were calculated from their mass ratio with helium, assuming that the diffusion coefficient of gas molecules in the underlying layers is inversely proportional to the molecular weight of the gas molecules.

[0154] For nitrogen and the solubility coefficient of nitrogen in the substrate, as shown in Comparative Example 5 in Table 5 below, the calculated filling time when the substrate is 200 nm thick was adopted as a value that matched the measured filling time when the substrate is 200 nm thick.

[0155] The solubility coefficient of carbon dioxide in the substrate was determined by assuming that the ratio of the solubility coefficient of carbon dioxide in the substrate to the solubility coefficient of nitrogen in the substrate is equal to the ratio of the solubility coefficient of carbon dioxide in the curable composition (A2) to the solubility coefficient of nitrogen in the curable composition (A2).

[0156] The diffusion coefficient and solubility coefficient of the gas mixture were calculated using weighted average values ​​according to the molar ratio of each gas.

[0157] [Comparative Example 1, Comparative Example 2, Comparative Example 3] In a pattern formation method without a base layer, the filling time was calculated using helium, nitrogen, and carbon dioxide as the atmospheric gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the curable composition droplet was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculated filling time results and measured values ​​are shown in Table 4.

[0158] [Table 4]

[0159] [Comparative Example 4, Comparative Example 5, Example 1] In pattern formation with a substrate thickness of 200 nm, the filling time was calculated using helium, nitrogen, and carbon dioxide as the ambient gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 2. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculated filling time results and measured values ​​are shown in Table 5.

[0160] [Table 5]

[0161] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere.

[0162] [Comparative Example 6, Comparative Example 7, Example 2] In pattern formation with a substrate thickness of 50 nm, the filling time was calculated using helium, nitrogen, and carbon dioxide as the atmospheric gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time are shown in Table 6.

[0163] [Table 6]

[0164] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere. [Comparative Example 8, Comparative Example 9, Example 3] In pattern formation with a substrate thickness of 40 nm, the filling time was calculated using helium, nitrogen, and carbon dioxide as the atmospheric gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time are shown in Table 7.

[0165] [Table 7]

[0166] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere. [Comparative Example 10, Comparative Example 11, Example 4] In pattern formation with a substrate thickness of 30 nm, the filling time was calculated using helium, nitrogen, and carbon dioxide as the ambient gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time are shown in Table 8.

[0167] [Table 8]

[0168] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere. [Comparative Example 12, Comparative Example 13, Example 5] In pattern formation with a substrate thickness of 20 nm, the filling time was calculated using helium, nitrogen, and carbon dioxide as the atmospheric gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time are shown in Table 9.

[0169] [Table 9]

[0170] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere. [Comparative Example 14, Comparative Example 15, Example 6] In pattern formation with a substrate thickness of 10 nm, the filling time was calculated using helium, nitrogen, and carbon dioxide as the ambient gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time are shown in Table 10.

[0171] [Table 10]

[0172] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere. [Comparative Example 16, Example 7] In pattern formation with a substrate thickness of 5 nm, the filling time was calculated using helium and carbon dioxide as the ambient gas (gas in the gap) by inputting the various coefficients listed in Tables 1 and 3. The volume of the droplet of the curable composition (A2-1) was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time are shown in Table 11.

[0173] [Table 11]

[0174] Theoretical calculations confirmed that the filling time is shorter in a carbon dioxide atmosphere.

[0175] [Comparative Example 17, Example 8, Example 9, Example 10] In pattern formation with a substrate thickness of 50 nm, the filling time was calculated when the ambient gas (gas in the gap) was a mixture of nitrogen and carbon dioxide. The droplet volume was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results of the filling time and the physical properties of the mixed gas are shown in Table 12.

[0176] [Table 12]

[0177] Theoretical calculations confirmed that when a mixture of nitrogen and carbon dioxide is used as the ambient gas, the filling time becomes shorter than 1 second when the molar ratio of carbon dioxide is 25% or higher.

[0178] [Comparative Example 18, Comparative Example 19, Example 11, Example 12, Example 13, Example 14] In pattern formation with a substrate thickness of 50 nm, the filling time was calculated when the ambient gas (gas in the gap) was a mixture of oxygen and carbon dioxide. The droplet volume was set to 3.5 pl, the film thickness after filling to 28 nm, and the initial droplet diameter to 100 μm. The mold thickness was set to 1 mm. The calculation results for the filling time and the physical properties of the mixed gas are shown in Table 13.

[0179] [Table 13]

[0180] Theoretical calculations confirmed that in a mixed gas atmosphere of oxygen and carbon dioxide, the filling time becomes shorter than 1 second when the molar ratio of carbon dioxide is 25% or higher.

[0181] <Example of theoretical calculation of filling time related to flattening> The filling time in a planarization method using a 2000nm thick Cytop (manufactured by AGC) as the protective layer of the mold was calculated as follows.

[0182] Table 14 summarizes the diffusion coefficients of the organic material or protective layer on the mold surface, the curable composition (A2-2), and the gases (helium, nitrogen, carbon dioxide) in the silicon substrate, as well as the solubility coefficients of the gases in the silicon substrate, which are necessary for the theoretical calculation of the filling time.

[0183] [Table 14]

[0184] The basis for the physical properties listed in Table 14 is explained below.

[0185] For the solubility coefficient of the organic material or protective layer on the mold surface, and the diffusion coefficient in the organic material or protective layer on the mold surface, known values ​​were used.

[0186] For the solubility coefficient and diffusion coefficient in the curable composition (A2-2), the values ​​for isobornyl acrylate were used, as in Table 3.

[0187] The solubility coefficient and diffusion coefficient in the silicon substrate were set to zero, as in Table 3.

[0188] [Comparative Example 20, Comparative Example 21, Example 15] In planarization with an organic material or protective layer thickness of 2000 nm on the mold surface, the filling time was calculated using helium, nitrogen, and carbon dioxide as the atmospheric gas (gas in the gap) by inputting the various coefficients listed in Tables 2 and 14. The volume of the droplet of curable composition (A2-2) was 1 pl, the film thickness after filling was 60 nm, and the diameter of the droplet at the start was 100 μm. The calculated filling times are shown in Table 15.

[0189] [Table 15]

[0190] Theoretical calculations have confirmed that in a carbon dioxide atmosphere (gas in the gap = carbon dioxide), the filling time is shorter than that of nitrogen and comparable to that of helium. Furthermore, since carbon dioxide gas is generally cheaper than helium gas, if the filling time is equivalent to that of helium, the cost of the atmosphere gas can be reduced without compromising throughput. [Comparative Example 22, Example 16] The filling time in the pattern formation method of this embodiment was measured by the following experiment. FNIS-031A manufactured by Fujifilm Corporation was used as the curable composition (A2-3). ODL-301 manufactured by Shin-Etsu Chemical Co., Ltd. was used as the underlayer material. 0.6 pL droplets of the curable composition (A2-3) were dropped onto a 26 × 33 mm area of ​​a silicon substrate coated with a 200 nm thick layer of ODL-301, at a uniform density to achieve an average film thickness of 32 nm. A quartz blank mold was then brought into contact with the substrate using carbon dioxide or helium as the atmospheric gas. After contact, ultraviolet light was irradiated through the mold after a predetermined waiting time to cure the curable composition (A2-3), and the mold was separated to obtain a cured film of the curable composition (A2-3). The number of defects in the cured film due to residual air bubbles was counted. The density of defects was 10 units / cm³. 2 The waiting time that falls below this limit was defined as the refueling time.

[0191] In all atmospheric gases, the longer the waiting time, the smaller the density of the defect portion. The filling time was less than 0.7 seconds for carbon dioxide (Example 16), while it took 0.9 seconds for helium (Comparative Example 22).

[0192] The following describes a method for manufacturing articles using the above-described film formation method or pattern formation method. The cured film or pattern of the cured material formed by the above-described film formation method or pattern formation method is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. Articles include electrical circuit elements, optical elements, MEMS, recording elements, sensors, or molds. Examples of electrical circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, as well as semiconductor elements such as LSI, CCD, image sensors, and FPGAs. Examples of optical elements include microlenses, light guides, waveguides, anti-reflective films, diffraction gratings, polarizing elements, color filters, light-emitting elements, displays, and solar cells. Examples of MEMS include DMDs, microfluidics, and electromechanical conversion elements. Examples of recording elements include optical discs such as CDs and DVDs, magnetic discs, magneto-optical discs, and magnetic heads. Examples of sensors include magnetic sensors, optical sensors, and gyro sensors. Examples of molds include molds for imprinting.

[0193] The pattern of the cured material is either used as is as a component of at least a part of the above-mentioned article, or temporarily used as a resist mask. After etching or ion implantation is performed during the substrate processing process, the resist mask is removed.

[0194] Next, a method for manufacturing articles will be described, which involves forming a pattern on a substrate using an imprinting device, processing the substrate on which the pattern has been formed, and manufacturing an article from the processed substrate. As shown in Figure 5(a), a substrate 1z such as a silicon wafer is prepared on which a workpiece material 2z such as an insulator is formed on its surface. Subsequently, an imprint material 3z is applied to the surface of the workpiece material 2z by an inkjet method or the like. This shows how multiple droplet-shaped imprint material 3z are applied to the substrate.

[0195] As shown in Figure 5(b), the mold 4z for imprinting is positioned opposite the imprint material 3z on the substrate, with the side where the uneven pattern is formed facing it. As shown in Figure 5(c), the substrate 1 to which the imprint material 3z is applied and the mold 4z are brought into contact, and pressure is applied. The imprint material 3z fills the gap between the mold 4z and the workpiece 2z. In this state, when light is irradiated through the mold 4z as curing energy, the imprint material 3z hardens.

[0196] As shown in Figure 5(d), after the imprint material 3z has hardened, when the mold 4z and substrate 1z are separated, a pattern of the hardened imprint material 3z is formed on the substrate 1z. In this pattern, the recesses of the mold correspond to the protrusions of the hardened material, and the protrusions of the mold correspond to the recesses of the hardened material. In other words, the uneven pattern of the mold 4z has been transferred to the imprint material 3z.

[0197] As shown in Figure 5(e), when etching is performed using the cured material pattern as an etching-resistant mask, the parts of the workpiece 2z surface that are free of or have a thin remaining cured material are removed, forming grooves 5z. As shown in Figure 5(f), when the cured material pattern is removed, an article with grooves 5z formed on the surface of the workpiece 2z can be obtained. Here, the cured material pattern was removed, but it may also be used without removal after processing, for example, as an interlayer insulating film included in semiconductor devices, i.e., as a component of the article.

[0198] Next, other methods for manufacturing articles will be described. As shown in Figure 6(a), a substrate 1y such as quartz glass is prepared, and then an imprint material 3y is applied to the surface of the substrate 1y by an inkjet method or the like. If necessary, a layer of another material such as metal or a metal compound may be provided on the surface of the substrate 1y.

[0199] As shown in FIG. 6(b), an imprint mold 4y is opposed to an imprint material 3y on a substrate with the side having its concavo-convex pattern facing the imprint material 3y on the substrate. As shown in FIG. 6(c), the substrate 1y provided with the imprint material 3y is brought into contact with the mold 4y and pressure is applied. The imprint material 3y is filled in the gap between the mold 4y and the substrate 1y. When light is irradiated through the mold 4y in this state, the imprint material 3 is cured.

[0200] As shown in FIG. 6(d), after the imprint material 3y is cured and then the mold 4y and the substrate 1y are separated, a pattern of the cured product of the imprint material 3y is formed on the substrate 1y. Thus, an article having the pattern of the cured product as a component member is obtained. In addition, if the substrate 1y is etched using the pattern of the cured product as a mask in the state of FIG. 6(d), an article in which the concave and convex portions are inverted with respect to the mold 4y, for example, an imprint mold can also be obtained. Next, an article manufacturing method for manufacturing an article using a film forming method for forming a film having the above flat surface will be described. Hereinafter, the article manufacturing method includes a film forming step of forming a film on a substrate according to the above film forming method, and a processing step of processing the substrate on which the film is formed, and an article is manufactured from the substrate that has undergone those steps. The processing step may include, for example, a step of forming a photoresist film on the film, a step of forming a latent image on the photoresist film using an exposure apparatus, and a step of developing the latent image to form a photoresist pattern. The processing step may further include a step of processing the substrate 1 (for example, etching, ion implantation) using the photoresist pattern.

[0201] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Therefore, claims are attached to disclose the scope of the invention.

Claims

1. A film forming method for forming a film made of a curable composition using a mold having a surface made of organic material, A placement step of placing the curable composition on a substrate, A contact step is performed after the arrangement step, bringing the curable composition into contact with the surface of the mold. A curing step is performed after the contact step to cure the curable composition, The process includes a separation step of separating the curable composition and the mold after the curing step, In the contact process, there is a gas filling the space between the substrate and the mold. The aforementioned gas contains 25% or more carbon dioxide in molar proportions. The solubility coefficient of the gas in the organic material constituting the surface of the mold is 0.5 kg / m³. ３ ・ATM or more 10kg / m ３ - It is less than or equal to ATM. A film formation method characterized by the following:

2. The mold has a flat surface and undergoes the contact step, the curing step and the separation step. Then, the film having a surface that conforms to the flat surface is formed. The film formation method according to feature 1.

3. The mold has a pattern and performs the contact step, the curing step and the separation step. Subsequently, the film on which the pattern is transferred is formed. The film formation method according to claim 1 or 2.

4. A film-forming method for forming a film made of a curable composition using a mold having a surface made of organic material, A placement step of placing the curable composition on a substrate, A contact step is performed after the arrangement step, bringing the curable composition into contact with the surface of the mold, A curing step is performed after the contact step to cure the curable composition, The process includes a separation step of separating the curable composition and the mold after the curing step, In the contact process, there is a gas filling the space between the substrate and the mold. The solubility coefficient of the gas in the curable composition is 10 kg / m³. ３ - It is less than or equal to ATM, The solubility coefficient of the gas in the organic material is S [kg / m³] ３ - atm], the diffusion coefficient of the gas in the organic material is D [m ２ When / s], S and D are 0.5 × 10 －１０ The above 10 x 10 －１０ The following is: A film formation method characterized by the following:

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