WO2016098314A1 - Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component - Google Patents

Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component Download PDF

Info

Publication number
WO2016098314A1
WO2016098314A1 PCT/JP2015/006106 JP2015006106W WO2016098314A1 WO 2016098314 A1 WO2016098314 A1 WO 2016098314A1 JP 2015006106 W JP2015006106 W JP 2015006106W WO 2016098314 A1 WO2016098314 A1 WO 2016098314A1
Authority
WO
WIPO (PCT)
Prior art keywords
adhesion layer
meth
substrate
compound
acrylate
Prior art date
Application number
PCT/JP2015/006106
Other languages
French (fr)
Inventor
Tomonori OTANI
Toshiki Ito
Takeshi Honma
Original Assignee
Canon Kabushiki Kaisha
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2015187477A external-priority patent/JP6704701B2/en
Application filed by Canon Kabushiki Kaisha filed Critical Canon Kabushiki Kaisha
Priority to KR1020177018766A priority Critical patent/KR101952058B1/en
Publication of WO2016098314A1 publication Critical patent/WO2016098314A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3105—After-treatment
    • H01L21/311—Etching the insulating layers by chemical or physical means
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G75/00—Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen, or carbon in the main chain of the macromolecule
    • C08G75/02—Polythioethers
    • C08G75/04—Polythioethers from mercapto compounds or metallic derivatives thereof
    • C08G75/045—Polythioethers from mercapto compounds or metallic derivatives thereof from mercapto compounds and unsaturated compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G75/00—Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen, or carbon in the main chain of the macromolecule
    • C08G75/02—Polythioethers
    • C08G75/0204—Polyarylenethioethers
    • C08G75/0209—Polyarylenethioethers derived from monomers containing one aromatic ring
    • C08G75/0213—Polyarylenethioethers derived from monomers containing one aromatic ring containing elements other than carbon, hydrogen or sulfur
    • C08G75/0222—Polyarylenethioethers derived from monomers containing one aromatic ring containing elements other than carbon, hydrogen or sulfur containing nitrogen
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/0002—Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/027—Non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/004—Photosensitive materials
    • G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
    • G03F7/11—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers having cover layers or intermediate layers, e.g. subbing layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/027—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34
    • H01L21/0271—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers

Definitions

  • the present invention relates to an adhesion layer composition, methods for forming an adhesion layer and a cured product, and methods for manufacturing an optical component, a circuit board, an imprinting mold and a device component.
  • MEMS microelectromechanical systems
  • a mold having a fine relief pattern in the surface thereof is pressed against a substrate to which a photocurable composition (resist) has been applied, and the photocurable composition is cured in this state.
  • the relief pattern of the mold is transferred to the cured film of the photocurable composition, thereby forming a pattern on the substrate.
  • the photo-nanoimprinting technique enables a fine structure of the order of several nanometers to be formed on a substrate.
  • a photocurable composition is applied to the region on a substrate to which a pattern will be formed (disposing step). Subsequently, the photocurable composition is shaped in a mold having a pattern (mold contact step). Then, the photocurable composition is cured by being irradiated with light (irradiation step), and separated from the mold (mold-releasing step). Through these steps, a resin pattern (photo-cured film) having a specific shape is formed on the substrate.
  • adhesion between the photocurable composition and the substrate is important. If the adhesion between the photocurable composition and the substrate is low, part of the photo-cured product of the photocurable composition can remain undesirably in the mold and be removed from the substrate together with the mold when the mold is removed. This is a cause of a defect of pattern separation.
  • a technique is devised for increasing the adhesion between the photocurable composition and the substrate by forming an adhesion layer between the photocurable composition and the substrate (PTL 1).
  • the adhesion layer is formed using an organic compound having in the molecule thereof a thiol group and a reactive functional group capable of forming a chemical bond with an organic compound.
  • the adhesion layer is required to have a high adhesion to the photocurable composition and the substrate, and, in addition, to have a high strength so as to be a strong film.
  • the organic compound disclosed in PTL 1 is used for binding the thiol group to the substrate, and for binding the reactive functional group to the photocurable composition.
  • the adhesion between the photocurable composition and the substrate is thus increased, whereas the strength of the adhesion layer itself is insufficient.
  • An adhesion layer having a low strength can be broken in the mold-releasing step and cause a defect of pattern separation.
  • the present invention provides an adhesion layer composition that can reduce a defect of pattern separation.
  • an adhesion layer composition containing a compound (A) having at least three ethylenic unsaturated groups in the molecule thereof and a compound (B) having at least two thiol groups in the molecule thereof.
  • Fig. 1A is a schematic sectional view illustrating a method for forming a cured product pattern according to an embodiment of the present invention.
  • Fig. 1B is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • Fig. 1C is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • Fig. 1D is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • Fig. 1E is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • Fig. 1A is a schematic sectional view illustrating a method for forming a cured product pattern according to an embodiment of the present invention.
  • Fig. 1B is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the
  • FIG. 1F is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • Fig. 1G is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • Fig. 1H is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
  • the adhesion layer composition 100 (hereinafter referred to as the composition 100 in some cases) disclosed herein is intended to form an adhesion layer 101 between a substrate 102 and a photocurable composition 103 (hereinafter referred to as the composition 103 in some cases).
  • the adhesion layer composition 100 contains a compound (A) having at least three ethylenic unsaturated groups and a compound (B) having at least two thiol groups capable of binding to the ethylenic unsaturated groups.
  • the phrase "functional group (of Y) capable of binding to X" is a functional group that can form a chemical bond such as covalent bond, an ionic bond, a hydrogen bond, or a bond by intermolecular force between X and Y.
  • the "functional group (of Y) capable of binding to X” used herein is a functional group capable of forming a covalent bond between X and Y. Such a functional group can form a strong bond between X and Y.
  • the adhesion layer composition 100 of an embodiment of the present invention may be suitable for the case where it is applied onto a substrate 102 and cured to form a cured product.
  • a composite including the adhesion layer 101 formed by curing the adhesion layer composition 100 and a substrate 102 is suitably used as a substrate on which a photocurable composition 103 will be disposed for producing a photo-cured product 109.
  • the adhesion layer composition 100 can be used as an adhesion layer composition used for imprinting, and is, in particularly, useful as an adhesion layer composition used for photo-nanoimprinting.
  • Compound (A) used in the present embodiment has at least three ethylenic unsaturated groups in the molecule thereof.
  • the ethylenic unsaturated group of compound (A) is a functional group that will bind to the photocurable composition 103. More specifically, compound (A) forms a covalent bond with a polymerizable compound in the photocurable composition 103 by a chain transfer reaction with radicals produced in the photocurable composition 103 in an irradiation step described later. Thus a chemical bond is formed between the adhesion layer and the photocurable composition 103. Consequently, the adhesion between the adhesion layer 101 and the cured product 109 of the photocurable composition 103 is increased.
  • the ethylenic unsaturated groups of compound (A) are not particularly limited as long as they are functional groups that can bind to the photocurable composition 103, and can be selected according to the constituents and contents thereof of the photocurable composition 103.
  • a functional group that can easily form a covalent bond with the photocurable composition 103 is advantageous as an ethylenic unsaturated group of compound (A).
  • Such a functional group can form a strong bond between the adhesion layer 101 and the photocurable composition 103.
  • the ethylenic unsaturated group may be vinyl, allyl, (meth)acryloyl, or the like. If the photocurable composition 103 contains a (meth)acryloyl compound as a polymerizable compound, it is advantageous that the ethylenic unsaturated group be (meth)acryloyl, which forms easily a covalent bond with the photocurable compound.
  • a (meth)acryloyl group mentioned herein refers to the acryloyl group or the methacryloyl group.
  • the ethylenic unsaturated groups of compound (A) will form a sulfide bond with the thiol group of compound (B) by a thiol-ene reaction in an adhesion layer forming step described later.
  • the ethylenic unsaturated group of compound (A) is a functional group that can bind to compound (B).
  • part of the ethylenic unsaturated groups of compound (A) will form covalent bonds with the ethylenic unsaturated groups of other molecules of compound (A) by radical chain transfer reaction among the molecules.
  • compound (A) Because of the three or more ethylenic unsaturated groups of compound (A), compound (A) has the function of forming a cross link between compound (B) and the photocurable composition 103 or the photo-cured product 109 of the photocurable composition 103 by the mechanism described above. Compound (A) also has the function of forming a cross link between two molecules thereof or a cross link with compound (B).
  • the amount of free molecules of compounds (A) and (B) not binding to the substrate 102 can be reduced.
  • the strength of the adhesion layer 101 can be increased.
  • the photocurable composition 103 is varied in constitution and, accordingly, the properties thereof are changed in such a manner, for example, that there occurs a defect such as separation of the pattern of the cured product 109 of the photocurable composition 103.
  • the use of the adhesion layer composition 100 of the present embodiment considerably reduces the amount of free molecules of compound (A) or (B) not binding to the substrate 102 in the adhesion layer 101 in comparison with the known techniques.
  • the dissolution of compound (A) or (B) into the photocurable composition 103 in the step of applying the composition 103 can be significantly reduced. Consequently, a defect such as separation of the pattern of the photo-cured product 109 can be prevented.
  • compound (A) having a larger number of ethylenic unsaturated groups forms a more three-dimensional cross-linked structure, accordingly increasing the strength of the adhesion layer 101. Also, such compound (A) facilitates the formation of chemical bonds among molecules thereof, between compound (A) and compound (B), and between compound (A) and the photocurable composition 103. Therefore the number of ethylenic unsaturated groups of compound (A) is at least three, and desirably four or more, more desirably six or more.
  • the ethylenic unsaturated group may be vinyl or acrylic group
  • the compounds having at least three vinyl or acrylic groups that can be used as compound (A) include, but are not limited to, 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane, 1,2,4-trivinylcyclohexane, triallylamine, triallyl 1,3,5-benzenetricarboxylate, triallyl citrate, triallyl cyanurate, triallyl isocyanurate, triallyl phosphorate, tetraallyloxyethane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane, and pentaerythritol triallyl ether.
  • Compound (A) may be a monofunctional (meth)acrylic compound having a (meth)acryloyl group, and examples thereof include, but are not limited to, 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)acryl
  • Compound (A) may be a polyfunctional (meth)acrylic compound having two (meth)acryloyl groups, and examples thereof include, but are not limited to, trimethylolpropane di(meth)acrylate, dimethyloltricyclodecane diacrylate, 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, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-adamantane dimethanol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, bis(hydroxymethyl)tricyclodecane di(meth)acrylate, EO-modified 2,2-bis(4-((meth
  • Compound (A) may be a polyfunctional (meth)acrylic compound having at least three (meth)acryloyl groups, and examples thereof include, but are not limited to, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate, EO/PO-modified trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tris(acryloyloxy)isocyanurate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.
  • (meth)acrylate refers to an acrylate or the methacrylate containing the same alcohol residue as the acrylate.
  • EO represents ethylene oxide
  • EO-modified compound Z is a compound in which the (meth)acrylic acid residue and alcohol residue of compound Z are bound to each other with an ethylene oxide block structure therebetween.
  • PO represents propylene oxide
  • PO-modified compound W is a compound in which the (meth)acrylic acid residue and alcohol residue of compound Z are bound to each other with a propylene oxide block structure therebetween.
  • Compound (B) used in the present embodiment has at least two thiol groups in the molecule thereof.
  • the thiol group of compound (B) is a functional group that will bind to the substrate 102.
  • the thiol group of compound (B) forms any one of chemical bonds, such as a covalent bond, a hydrogen bond or a bond by intermolecular force, with a functional group present at the surface of the substrate 102 in the adhesion layer forming step described later. More specifically, the adhesion layer 101 and the substrate 102 are bound to each other with a sulfur atom therebetween. Consequently, the adhesion between the adhesion layer 101 and the substrate 102 is increased.
  • the thiol groups of compound (B) will form sulfide bonds with part of the ethylenic unsaturated groups of compound (A) by a thiol-ene reaction in the adhesion layer forming step described later.
  • the thiol group of compound (B) is a functional group that will bind to compound (A).
  • compound (B) Because of the two or more thiol groups of compound (B), compound (B) has the function of forming a cross link between the substrate 102 and compound (A) or between the molecules of compound (A) by the mechanism described above.
  • the amount of free molecules of compounds (A) and (B) not binding to the substrate 102 can be reduced.
  • the dissolution of compound (A) or (B) into the photocurable composition 103 in the step of applying the photocurable composition 103 can be significantly reduced, and a defect such as separation of the pattern of the photo-cured product 109 can be prevented.
  • compound (B) has three or more thiol groups.
  • Compound (B) having three or more thiol groups forms a more three-dimensional cross-linked structure, accordingly increasing the strength of the adhesion layer 101.
  • such compound (B) facilitates the formation of chemical bonds with compound (A) and with the substrate 102.
  • compound (B) is more effective in the above-described point of view. More advantageously, compound (B) has four or more thiol groups.
  • Examples of the compound having at least two thiol groups that can be used as compound (B) include, but are not limited to, bifunctional thiol compounds, such as 1,4-bis(3-mercaptobutyryloxy)butane; trifunctional thiol compounds, such as 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate), and pentaerythritol tris(3-mercaptobutyrate); and tetrafunctional thiol compounds, such as pentaerythritol tetrakis(mercaptoacetate), pentaerythritol tetrakis(3-mercaptobutyrate), and pentaerythritol tetrakis(3-mercaptopropionate).
  • bifunctional thiol compounds
  • Compound (A) and compound (B) each may be composed of a single compound or a combination of a plurality of compounds.
  • compound (A) have three or more ethylenic unsaturated groups, or that compound (B) have three or more thiol groups.
  • Such compound (A) and compound (B) can easily form a three-dimensional cross-linked structure, accordingly increasing the strength of the adhesion layer 101 that is formed by curing the adhesion layer composition 100.
  • the total number of thiol groups in the adhesion layer composition 100 is excessively large relative to the total number of ethylenic unsaturated groups, all the ethylenic unsaturated groups of compound (A) can be used for the reaction with the thiol groups of compound (B) in the adhesion layer forming step. Consequently, the surface of the adhesion layer 101 opposite the substrate 102 becomes short of ethylenic unsaturated groups.
  • the ethylenic unsaturated group is the functional group intended to bind to the photocurable composition 103 applied on the surface of the adhesion layer 101 opposite the substrate 102. Therefore the adhesion between the adhesion layer 101 and the photocurable composition 103 becomes insufficient.
  • the proportions of compound (A) and compound (B) satisfy the following.
  • the functional group number ratio ⁇ / ⁇ of the total number ⁇ of ethylenic unsaturated groups to the total number ⁇ of the thiol groups is in the range of 1/9 to 9. More desirably, the ⁇ / ⁇ ratio is in the range of 1/2 to 9, and particularly in the range of 1 to 4.
  • a represents the number of ethylenic unsaturated groups in the molecule of compound (A);
  • n A represents the amount of compound (A) by mole in the adhesion layer composition 100; and
  • N A represents the Avogadro constant.
  • b represents the number of thiol groups in the molecule of compound (B);
  • n B represents the amount of compound (B) by mole in the adhesion layer composition 100; and
  • N A represents the Avogadro constant.
  • the total content of compounds (A) and (B) in the adhesion layer composition 100 may be determined according to the viscosity of the adhesion layer composition 100, the thickness of the adhesion layer, and the like.
  • the total content of compounds (A) and (B) may be in the range of 0.01% to 10% by weight, desirably in the range of 0.1% to 7% by weight, relative to the total weight of the composition 100.
  • the adhesion layer composition 100 contains a volatile solvent (C) (hereinafter simply referred to as solvent (C)). Solvent (C) in the adhesion layer composition 100 reduces the viscosity of the adhesion layer composition 100. Consequently, the adhesion layer composition 100 can be easily applied onto the substrate 102.
  • solvent C
  • Solvent (C) in the adhesion layer composition 100 reduces the viscosity of the adhesion layer composition 100. Consequently, the adhesion layer composition 100 can be easily applied onto the substrate 102.
  • Solvent (C) is not particularly limited as long as it can dissolve compound (A) and compound (B), and desirably has a boiling point of 80°C to 200°C under normal pressure. More desirably, solvent (C) is an organic solvent having at least one structure of an ester structure, a ketone structure, a hydroxy group, and an ether structure. Such a solvent is superior in dissolving compound (A) and compound (B) and in wetting the substrate 102.
  • solvent (C) examples include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, cyclohexanone, 2-heptanone, ⁇ -butyrolactone, and ethyl lactate. These may be used singly or in combination. From the viewpoint of easily applying the adhesion layer composition, propylene glycol monomethyl ether acetate or a mixed solvent thereof is advantageous.
  • the content of solvent (C) in the adhesion layer composition 100 is appropriately determined according to the viscosities of compound (A) and compound (B), the ease of application of the composition, and the thickness of the adhesion layer 101, and the like.
  • the content of solvent (C) in the adhesion layer composition 100 may be 70% by mass or more, and is desirably 90% by mass or more, more desirably 95% by mass or more, relative to the total mass of the adhesion layer composition 100. If the content of solvent (C) in the adhesion layer composition 100 is less than 70% by mass, the composition might not have satisfactory characteristics for being applied.
  • the upper limit of the solvent (C) content in the adhesion layer composition 100 is not particularly limited, and is desirably 99.9% by mass.
  • the adhesion layer composition 100 of the present embodiment may further contain a thermal polymerization initiator (D).
  • Thermal polymerization initiator (D) in the adhesion layer composition 100 promotes polymerization reaction, thereby reducing the amount of unreacted compound (A). Consequently, it is suppressed that the unreacted compound (A) dissolves in the photocurable composition 103 (described later) applied onto the adhesion layer and adversely affects the photocurable composition 103.
  • thermal polymerization initiator (D) include azo compounds and organic peroxides. These compounds may be used singly or in combination.
  • Exemplary azo compounds include azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyronitrile), 2,2'-azobis-2-methylbutyronitrile, 1,1'-azobis(1-cyclohexanecarbonitrile), 2,2'-azobis(methylisobutyrate), 2,2'-azobis(2-amidinopropane)dihydrochloride, and 2,2'-azobis(N-butyl-2-methylpropionamide).
  • Exemplary organic peroxides include hydroperoxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxybenzoate, benzoyl peroxide, peroxy ketal, ketone peroxide, t-butyl peroxyacetate, 2,2-bis(t-butyldioxy)butane, t-butylbenzoyl peroxide, butyl 4,4-bis[(t-butyl)peroxy]pentanate, di-t-hexyl peroxide, t-butyl ⁇ -cumyl peroxide, di-t-butyl peroxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, and t-butyl hydroperoxide.
  • Such a compound examples include 2,2'-azobis(N-butyl-2-methylpropionamide), t-butyl peroxyacetate, 2,2-bis(t-butyldioxy)butane, t-butylbenzoyl peroxide, butyl 4,4-bis[(t-butyl)peroxy]pentanate, di-t-hexyl peroxide, t-butyl ⁇ -cumyl peroxide, di-t-butyl peroxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, and t-butyl hydroperoxide.
  • the adhesion layer composition 100 of the present embodiment may further contain additives (X) in addition to compounds (A) and (B), solvent (C) and thermal polymerization initiator (D), according to the use thereof within a range in which the intended effects of the present invention are produced.
  • additives include a surfactant, a crosslinking agent, a polymer component, an antioxidant, and a polymerization inhibitor.
  • the viscosity of the adhesion layer composition 100 of the present embodiment depends on the constituents and contents of the constituents, such as compound (A), compound (B), solvent (C), and thermal polymerization initiator (D), and is desirably in the range of 0.5 mPa*s to 20 mPa*s at 23°C. Desirably, it is in the range of 1 mPa*s to 10 mPa*s, such as 1 mPa*s to 5 mPa*s.
  • the adhesion layer composition 100 having a viscosity of 20 mPa*s or less can be easily applied to the substrate 102, and accordingly, the thickness of the coating of the adhesion layer composition 100 on the substrate 102 can be easily adjusted.
  • the impurity content in the adhesion layer composition 100 is as low as possible.
  • Impurities mentioned herein refer to constituents other than compound (A), compound (B), solvent (C), thermal polymerization initiator (D) and other additives (X).
  • adhesion layer composition 100 have been purified.
  • filtration through a filter is advantageous for purification.
  • the mixture of the constituents may be filtered through a filter having a pore size in the range of 0.001 ⁇ m to 5.0 ⁇ m. This filtration may be performed in a plurality of steps or repeated several times. The filtrate may be further filtered. A plurality of filters having different pore sizes may be used.
  • the filter may be made of, but not limited to, polyethylene, polypropylene, fluororesin, or nylon.
  • Impurities such as particulate matter can be removed from the adhesion layer composition 100 by such purification.
  • unexpected defects can be prevented which particulate matter or other impurities may cause in the adhesion layer formed by applying the adhesion layer composition 100.
  • the adhesion layer composition 100 of the present embodiment is used for manufacturing a circuit board used in semiconductor devices, it is desirable to avoid the contamination of the composition 100 with metallic impurities containing a metal atom as much as possible in order to prevent the metallic impurities from interfering with the operation of the resulting circuit board. In this instance, it is desirable to reduce the concentration of metallic impurities in the adhesion layer composition 100 to 10 ppm or less, more desirably 100 ppb or less.
  • the photocurable composition 103 used with the adhesion layer 101 formed of the adhesion layer composition 100 of the present embodiment generally contains a polymerizable compound (component (E)) and a photopolymerization initiator (component (F)).
  • Component (E) is a polymerizable compound.
  • the polymerizable compound mentioned used herein is a compound that reacts with a polymerizing factor, such as radicals, produced from the photopolymerization initiator (component (F)) and forms a polymer film by chain reaction (polymerization reaction).
  • the polymerizable compound, or component (E) may be composed of a single polymerizable compound or a combination of a plurality of polymerizable compounds.
  • the polymerizable compound may be a radically polymerizable compound.
  • the radically polymerizable compound may have one or more acryloyl group or methacryloyl group, and hence may be a (meth)acrylic compound.
  • the polymerizable compound, or component (E) desirably contains a (meth)acrylic compound. Also, it is more desirable that the (meth)acrylic compound be the main constituent of component (E). Optimally, component (E) is a (meth)acrylic compound. When a (meth)acrylic compound is the main constituent of component (E), the (meth)acrylic compound accounts for 90% by weight or more of component (E).
  • the radically polymerizable compound is a combination of a plurality of compounds each having at least one acryloyl group or methacryloyl group, it is advantageous that radically polymerizable compound contain a monofunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate monomer.
  • a monofunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate monomer By combining a monofunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate monomer, a strong cured film can be formed.
  • Examples of the monofunctional (meth)acrylic compound having one acryloyl group or methacryloyl group include, but are not limited to, 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
  • Some monofunctional (meth)acrylic compounds are commercially available, and examples thereof include, but are not limited to, Aronix series M101, M102, M110, M111, M113, M117, M5700, TO-1317, M120, M150 and M156 (each produced by Toagosei); MEDOL 10, MIBDOL 10, CHDOL 10, MMDOL 30, MEDOL 30, MIBDOL 30, CHDOL 30, LA, IBXA, 2-MTA, HPA, and Biscoat series #150, #155, #158, #190, #192, #193, #220, #2000, #2100 and #2150 (each produced by Osaka Organic Chemical Industry); Light Acrylates BO-A, EC-A, DMP-A, THF-A, HOP-A, HOA-MPE, HOA-MPL, PO-A, P-200A, NP-4EA and NP-8EA, and epoxy ester M-600A (each produced by Kyoeisha Chemical); KAYARAD TC110S, R
  • polyfunctional (meth)acrylic compound having two or more acryloyl or methacryloyl groups include, but are not limited to, 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, dimethyloltricyclodecane diacrylate, 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, 1,6-hex
  • the polyfunctional (meth)acrylic compound is commercially available, and example thereof include, but are not limited to, Yupimer UV SA1002 and Yupimer UV SA2007 (each produced by Mitsubishi Chemical); Biscoat series #195, #230, #215, #260, #335HP, #295, #300, #360, #700, GPT and 3PA (each produced by Osaka Organic Chemical Industry); Light Acrylates 4EG-A, 9EG-A, NP-A, DCP-A, BP-4EA, BP-4PA, TMP-A, PE-3A, PE-4A and DPE-6A (each produce by Kyoeisha Chemical); A-DCP, A-HD-N, A-NOD-N and A-DOD-N (each produced by Shin-Nakamura Chemical); KAYARAD PET-30, TMPTA, R-604, DPHA, DPCA-20, -30, -60 and -120, HX-620, D-310, and D-330 (each produced by Nippon Kay
  • (meth)acrylate refers to an acrylate or the methacrylate containing the same alcohol residue as the acrylate.
  • a (meth)acryloyl group mentioned herein refers to the acryloyl group or the methacryloyl group.
  • EO represents ethylene oxide
  • PO represents propylene oxide.
  • Component (F) is a photopolymerization initiator.
  • the photopolymerization initiator used herein is a compound capable of sensing light having a specific wavelength to produce a polymerizing factor (radicals)
  • the photopolymerization initiator is a radical generator that produces radicals with light (radiations, such as infrared radiation, visible light radiation, ultraviolet radiation, far ultraviolet radiation, X-ray radiation, charged particle radiation such as electron beams, and other radiation). More specifically, the photopolymerization initiator generates radicals with light having, for example, a wavelength in the range of 150 nm to 400 nm.
  • Component (F) may be composed of a single photopolymerization initiator or a combination of a plurality of photopolymerization initiators.
  • radical generators include, but are not limited to, substituted or unsubstituted 2,4,5-triarylimidazole dimers, 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 and benzophenone derivatives, such as N,N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4-chlorobenzophenone, 4,4'-dime
  • the radical generator may be commercially available, and examples thereof include, but are not limited to, Irgacure series 184, 369, 651, 500, 819, 907, 784 and 2959, CGI-1700, -1750 and -1850, CG24-61, Darocur series l116 and 1173, Lucirin TPO, LR 8893, and LR 8970 (each produced by BASF); and Ubecryl P36 (produced by UCB).
  • the proportion of component (F) to component (E) in the photocurable composition 103 may be in the range of 0.01% to 10% by weight, and is desirably in the range of 0.1% to 7% by weight.
  • the proportion of component (F) is 0.01% by weight or more relative to the total weight of components (E) in the photocurable composition 103, the photocurable composition 103 can be cured in a shorter time, thus increasing reaction efficiency. Also, when the proportion of component (F) is 10.0% by weight or less relative to the total weight of component (E), the resulting cured film tends to be prevented from being degraded in mechanical strength.
  • the photocurable composition 103 may further contain additives (G) in addition to component (E) and component (F) according to the use of the composition within a range in which the intended effects of the present invention are produced.
  • additives (G) include a sensitizer, a hydrogen donor, an internal releasing agent, a surfactant, an antioxidant, a solvent, a polymer component, and a polymerization initiator other than component (F).
  • the sensitizer is optionally added to promote the polymerization reaction or increase reaction conversion rate.
  • the sensitizer may be a sensitizing dye.
  • the sensitizing dye is a compound that is excited by absorbing light having a specific wavelength and interacts with component (F).
  • the phrase "interacts with” mentioned here implies that, for example, energy or electrons transfer from the excited sensitizing dye to component (F).
  • sensitizing dye examples 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, camphorquinone derivatives, acridine dyes, thiopyrylium salt-based dyes, merocyanine dyes, quinoline dyes, styryl quinoline dyes, ketocoumarin dyes, thioxanthene dyes, xanthene dyes, oxonol dyes, cyanine dyes, rhodamine dyes, and pyrylium salt-based dyes.
  • sensitizing dyes may be used singly or in combination.
  • the hydrogen donor is a compound that can react with an initiator radical generated from component (F) or a chain end radical, thereby producing a more reactive radical. It is advantageous to add a hydrogen donor when component (F) is a photoradical generator.
  • hydrogen donor examples include, but are not limited to, amine compounds, such as n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthiourea, s-benzylisothiuronium-p-toluene sulfonate, triethylamine, diethylaminoethyl methacrylate, triethylenetetramine, 4,4'-bis(dialkylamino)benzophenone, ethyl N,N-dimethylaminobenzate, isoamyl N,N-dimethylaminobenzoate, pentyl 4-(dimethylamino)benzoate, triethanolamine, and N-phenylglycine; and mercapto compounds, such as 2-mercapto-N-phenylbenzoimidazole and mercaptopropionic acid esters.
  • amine compounds such as n-butylamine, di-n-butyl
  • These hydrogen donors may be used singly or in combination.
  • the hydrogen donor may have a function as a sensitizer.
  • the proportion of each additive may be in the range of 0.1% to 20% by weight relative to the total weight of component (E). Desirably, it is in the range of 0.1% to 5.0% by weight, and more desirably in the range of 0.2% to 2.0% by weight.
  • the proportion of the sensitizer is 0.1% by weight or more relative to the total weight of component (E)
  • polymerization can be promoted more effectively.
  • the proportion of the sensitizer or the hydrogen donor to 5.0% by weight or less
  • the photocurable composition 103 can be cured into a polymer film having a sufficiently large molecular weight. Also, these constituents in such a proportion can be miscible with the photocurable composition 103 and prevent the degradation of the storage stability of the photocurable composition 103.
  • An internal releasing agent may be added to the photocurable composition 103 in order to reduce the interfacial bonding strength between a mold 104 and the photo-cured product 109 of the photocurable composition 103, that is, to reduce the force for removing the mold in a mold-releasing step described later.
  • the internal releasing agent mentioned herein is a releasing agent that has been added to the photocurable composition 103 in advance of applying the photocurable composition 103.
  • the internal releasing agent may be composed of a single material or a combination of a plurality of materials.
  • the internal releasing agent may be a surfactant, such as a silicone surfactant, a fluorosurfactant, or a hydrocarbon surfactant.
  • the internal releasing agent is not polymerizable.
  • the fluorosurfactant may be a polyalkylene oxide (such as polyethylene oxide or polypropylene oxide) adduct of an alcohol having a perfluoroalkyl group, or a polyalkylene oxide (such as polyethylene oxide or polypropylene oxide) adduct of perfluoropolyether.
  • the fluorosurfactant may have a hydroxy, alkoxy, alkyl, amino or thiol group or the like in a part (for example, a terminal group) of the molecule.
  • the fluorosurfactant may be a commercially available product.
  • the commercially available fluorosurfactant include, but are not limited to, Megafac series F-444, TF-2066, TF-2067 and TF-2068 (each produced by DIC); Fluorad series FC-430 and FC-431 (each produced by Sumitomo 3M); Surflon S-382 (produced by AGC); EFTOP EF-122A, 122B, 122C, EF-121, EF-126, EF-127 and MF-100 (each produced by Tochem Products); PF-636, PF-6320, PF-656 and PF-6520 (each produced by OMNOVA Solutions); Unidyne series DS-401, DS-403 and DS-451 (each produced by Daikin Industries); and Ftergent series 250, 251, 222F and 208G (each produced by Neos).
  • the internal releasing agent may be a hydrocarbon surfactant.
  • the hydrocarbon surfactant may be an alkyl alcohol polyalkylene oxide adduct produced by adding an alkylene oxide having a carbon number of 2 to 4 to an alkyl alcohol having a carbon number of 1 to 50.
  • alkyl alcohol polyalkylene oxide adduct examples include methyl alcohol ethylene oxide adduct, decyl alcohol ethylene oxide adduct, lauryl alcohol ethylene oxide adduct, cetyl alcohol ethylene oxide adduct, stearyl alcohol ethylene oxide adduct, and stearyl alcohol ethylene oxide/propylene oxide adduct.
  • the terminal group of the alkyl alcohol polyalkylene oxide adduct is not limited to the hydroxy group, which is formed by simply adding a polyalkylene oxide to an alkyl alcohol.
  • the hydroxy group may be substituted with a polar functional group, such as carboxy, amino, pyridyl, thiol, or silanol, or a hydrophobic functional group, such as alkyl or alkoxy.
  • a commercially available alkyl alcohol polyalkylene oxide adduct may be used.
  • the commercially available alkyl alcohol polyalkylene oxide adduct include, but are not limited to, polyoxyethylene methyl ethers (methyl alcohol ethylene oxide adducts), such as BLAUNON series MP-400, MP-550 and MP-1000 (each produced by Aoki Oil Industrial); polyoxyethylene decyl ethers (decyl alcohol ethylene oxide adducts), such as FINESURF series D-1303, D-1305, D-1307 and D-1310 (each produced by Aoki Oil Industrial); polyoxyethylene lauryl ethers (lauryl alcohol ethylene oxide adduct), such as BLAUNON EL-1505 (produced by Aoki Oil Industrial); polyoxyethylene cetyl ethers (cetyl alcohol ethylene oxide adducts), such as BLAUNON series CH-305 and CH-310 (each produced by Aoki Oil Industrial); polyoxyethylene stearyl ethers
  • alkyl alcohol polyalkylene oxide adducts are advantageous as the internal releasing agent.
  • the proportion of the internal releasing agent may be in the range of 0.001% to 10% by weight relative to the total weight of the polymerizable compound or component (E). Desirably, it is in the range of 0.01% to 7% by weight, and more desirably in the range of 0.05% to 5% by weight.
  • the proportion of the internal releasing agent is at least in the range of 0.001% to 10% by weight, the mold can be easily removed, and the photocurable composition can satisfactorily fill the mold.
  • At least components (E) and (F) are mixed and dissolved in each other at a predetermined temperature, for example, in the range of 0°C to 100°C.
  • a predetermined temperature for example, in the range of 0°C to 100°C.
  • G additives
  • the mixture of the constituents of the photocurable composition 103 other than solvent may have a viscosity in the range of 1 mPa*s to 100 mPa*s at 23°C. Desirably, it is in the range of 1 mPa*s to 50 mPa*s, such as 1 mPa*s to 20 mPa*s.
  • the photocurable composition 103 having a viscosity of 100 mPa*s or less can fill the recesses of the fine pattern of the mold 104 without taking a long time when the photocurable composition 103 is brought into contact with the mold 104.
  • the use of such a photocurable composition 103 enables photo-nanoimprinting with a high productivity. Also, filling failure that causes a defect in the resulting pattern is unlikely to occur.
  • the photocurable composition 103 having a viscosity of 1 mPa*s or more can be easily applied uniformly on the substrate 102, and is unlikely to flow out of the mold as the photocurable composition 103 is brought into contact with the mold.
  • the mixture of the constituents of the photocurable composition 103 other than solvent may have a surface tension in the range of 5 mN/m to 70 mN/m at 23°C. Desirably, it is in the range of 7 mN/m to 35 mN/m, such as 10 mN/m to 32 mN/m.
  • the photocurable composition 103 having a surface tension of 5 mN/m or more can fill the recesses of the fine pattern of the mold 104 without taking a long time as the photocurable composition 103 is brought into contact with the mold 104.
  • the photocurable composition 103 has a surface tension of 70 mN/m or less
  • the cured film 109 formed by irradiating the photocurable composition 103 with light has a smooth surface.
  • the impurity content in the photocurable composition 103 is as low as possible.
  • the photocurable composition 103 have been purified as with the adhesion layer composition 100.
  • filtration through a filter is advantageous for purification.
  • the mixture of the above-described constituents may be filtered through a filter having a pore size in the range of 0.001 ⁇ m to 5.0 ⁇ m. This filtration may be performed in a plurality of steps or repeated several times. The filtrate may be further filtered. A plurality of filters having different pore sizes may be used.
  • the filter may be made of, but not limited to, polyethylene, polypropylene, fluororesin, or nylon.
  • Impurities such as particulate matter can be removed from the photocurable composition 103 by such purification.
  • unexpected pattern defects can be prevented which result from unevenness caused by particulate matter or other impurities in the cured film 109 formed by curing the photocurable composition 103.
  • the photocurable composition 103 is used for manufacturing a circuit board used in semiconductor devices, it is desirable to avoid the contamination with metallic impurities containing a metal atom as much as possible in order to prevent the metallic impurities from interfering with the operation of the resulting circuit board. In this instance, it is desirable to reduce the concentration of metallic impurities in the photocurable composition 103 to 10 ppm or less, more desirably 100 ppb or less.
  • FIGs. 1A to 1H are schematic sectional views illustrating a method for forming a cured product pattern according to the present embodiment.
  • the method for forming a cured product pattern includes: (1) a first step of forming an adhesion layer on a substrate, using the adhesion layer composition of an embodiment of the invention (adhesion layer forming step); (2) a second step of disposing a photocurable composition on the substrate (disposing step); (3) a third step of bringing the photocurable composition into contact with a mold (mold contact step); (5) a fourth step of irradiating the photocurable composition with light with the mold in contact therewith (irradiation step); and (6) a fifth step of removing the mold from the cured film formed in the fourth step (mold-releasing step).
  • the method may include the following step between the third and the fourth step: (4) a step of aligning the mold with the substrate (alignment step).
  • This method for forming a cured product pattern incorporates a photo-nanoimprinting technique.
  • the cured product pattern formed by the method of the present embodiment may have a line width in the range of 1 nm to 10 mm, advantageously in the range of 10 nm to 100 ⁇ m.
  • methods for forming nanometer scale (1 nm to 100 nm) patterns (having a relief structure) using light are called photo-nanoimprinting.
  • an adhesion layer 101 mainly containing a polymer is formed on a substrate 102, as shown in Fig. 1A, using the above-described adhesion layer composition 100.
  • the substrate 102 is a workpiece to which the photocurable composition 103 will be disposed (applied) and is typically silicon wafer. Since the silicon wafer has silanol groups and hydroxy groups at the surface thereof. Accordingly, it is expected that chemical bonds are easily formed between the substrate 102 and the thiol groups of compound (B) by heating. Thus, the adhesion layer 101 and the substrate 102 are bound to each other with sulfur atoms therebetween.
  • the substrate 102 is however not limited to silicon wafer.
  • the substrate 102 may be arbitrarily selected from among substrates used for semiconductor devices, such as substrates made of aluminum, titanium-tungsten alloy, aluminum-silicon alloy, aluminum-copper-silicon alloy, silicon oxide, or silicon nitride.
  • the substrate 102 may be a substrate provided thereon with one or more films, such as a spin-on-glass film, an organic film, a metal film, an oxide film, and a nitride film.
  • the substrate 102 has hydroxy groups at the surface thereof. This is because the hydroxy groups at the surface of the substrate 102 facilitates the formation by heating of chemical bonds between the substrate 102 and the thiol groups of compound (B).
  • the adhesion layer composition 100 may be applied onto the substrate 102 by, for example, an ink jet method, dip coating, air knife coating, curtain coating, wire bar coating, gravure coating, extrusion coating, spin coating, or a slit scan method. From the viewpoint of easy application, particularly of forming a uniform thickness, spin coating is advantageous.
  • solvent (C) is removed from the adhesion layer composition 100 by drying.
  • solvent (C) is desirable to perform reactions between compound (B) and the substrate 102 and between compound (A) and compound (B) simultaneously with the removal of solvent (C).
  • chemical bonds are formed between the substrate 102 and the adhesion layer 101 and between compounds (A) and (B) in the adhesion layer 101.
  • the chemical bond between compound (A) and compound (B) is a sulfide bond formed by a thiol-ene reaction between the ethylenic unsaturated group of compound (A) and the thiol group of compound (B).
  • the substrate 102 and the adhesion layer composition 100 are desirably heated.
  • the heating temperature for the reactions is set depending on the reactivity between compound (B) and the substrate 102, the reactivity between compound and compound (B), and the boiling points of compound (A), compound (B) and solvent (C), and other factors.
  • the heating temperature may be in the range of 70°C to 250°C, and is desirably in the range of 100°C to 220°C, such as 140°C to 220°C.
  • the drying of solvent (C), the reaction between the substrate 102 and compound (B), and the crosslinking reaction between compound (A) and compound (B) may be performed at the same temperature or different temperatures. Hence, these operation and reactions may be performed at one time or one after another.
  • the thickness of the adhesion layer 101 formed by applying the adhesion layer composition 100 onto the substrate 102 depends on use, and may be, for example, in the range of 0.1 nm to 100 nm. Desirably, it is in the range of 0.5 nm to 60 nm, such as 1 nm to 10 nm.
  • a multilayer adhesion layer 101 may be formed by repeating the application of the adhesion layer composition 100 in such a manner that another adhesion layer is formed on a previously formed adhesion layer.
  • the resulting adhesion layer 101 is as flat as possible.
  • the surface roughness of the adhesion layer is desirably 1 nm or less.
  • a composite including the substrate 102 and the adhesion layer 101 formed on the substrate 102 are formed as below.
  • the adhesion layer 101 contains sulfide bonds formed by a thiol-ene reaction between the ethylenic unsaturated group of compound (A) and the thiol group of compound (B). Also, the adhesion layer 101 and the substrate 102 are bound to each other by the thiol group of compound (B), hence binding together with a sulfur atom therebetween.
  • the adhesion layer 101 contains sulfur atoms deriving from compound (B), and many of the sulfur atoms are present at the surface of the adhesion layer 101 adjacent to the substrate 102.
  • the thiol group of compound (B) is a functional group capable of binding to the substrate 102 and, accordingly, the molecules of compound (B) are likely to be distributed close to the substrate 102 by the adhesion layer forming step.
  • compound (B) binding to the substrate 102 reacts with compound (A).
  • many of the sulfur atoms deriving from compound (B) are present at the surface of the adhesion layer 101 adjacent to the substrate 102.
  • ethylenic unsaturated groups deriving from compound (A) are present at the surface of the adhesion layer 101 opposite the substrate 102.
  • the ethylenic unsaturated groups enable the adhesion layer 101 to be bound to the photocurable composition 103 through the steps of (2) to (5).
  • the photocurable composition 103 is applied onto the adhesion layer 101 on the substrate 102, and thus a coating film of the composition 103 is disposed on the substrate 102, as shown in Fig. 1B.
  • the photocurable composition 103 may be applied by, for example, an ink jet method, dip coating, air knife coating, curtain coating, a wire bar coating, gravure coating, extrusion coating, spin coating, or a slit scan method.
  • an ink jet method is particularly suitable.
  • the thickness of the coating film of the photocurable composition depends on use, and may be, for example, in the range of 0.01 ⁇ m to 100.0 ⁇ m.
  • the coating film of the photocurable composition 103 formed in the preceding disposing step is brought into contact with a mold 104 having an original pattern to be transferred, as shown in Fig. 1C (c-1).
  • a mold 104 having an original pattern to be transferred as shown in Fig. 1C (c-1).
  • the recesses of the original fine pattern in the surface of the mold 104 are filled with (part of) the photocurable composition 103, so that a coating film 105 filling the fine pattern of the mold 104 is formed (Fig. 1C (c-2)).
  • the mold 104 is made of an optically transparent material in view of the subsequent irradiation step.
  • the material of the mold 104 include glass, quartz, optically transparent resins, such as polymethyl methacrylate (PMMA) and polycarbonate, transparent metal films formed by vapor deposition, soft films of polydimethylsiloxane or the like, photo-cured films, and metal films. If an optically transparent resin is used as the material of the mold 104, the optically transparent resin is a material insoluble in any constituent of the photocurable composition 103. Quartz is particularly suitable as the material of the mold 104 because it has a small thermal expansion coefficient and is accordingly unlikely to deform the pattern.
  • the fine pattern in the surface of the mold 104 may have a height in the range of 4 nm to 200 nm and each trace of the pattern may have an aspect ratio in the range of 1 to 10.
  • the mold 104 may be surface-treated before the mold contact step so that the mold 104 can be easily removed from the photocurable composition 103.
  • a releasing agent may be applied to the surface of the mold 104.
  • Examples of the releasing agent to be applied to the surface of the mold 104 include silicone releasing agents, fluorine-based releasing agents, hydrocarbon releasing agents, polyethylene-based releasing agents, polypropylene-based releasing agents, paraffin releasing agents, montanic releasing agents, and carnauba releasing agents.
  • the pressure (mold pressure) applied to the photocurable composition 103 is not particularly limited, but is typically in the range of 0 MPa to 100 MPa.
  • the pressure is desirably in the range of 0 MPa to 50 MPa, and more desirably in the range of 0 MPa to 30 MPa, such as 0 MPa to 20 MPa.
  • the period of time for which the mold 104 is kept in contact with the photocurable composition 103 is not particularly limited. It is typically in the range of 0.1 s to 600 s, and is desirably in the range of 0.1 s to 300 s, more desirably in the range of 0.1 s to 180 s, such as 0.1 s to 120 s.
  • the mold contact step can be performed in any atmosphere of atmospheres of air, reduced pressure and an inert gas, it is advantageous that the mold contact step is performed in an atmosphere of reduced pressure or an inert gas, from the viewpoint of preventing oxygen or moisture from affecting the curing reaction.
  • Inert gases that can be used in this step include nitrogen, carbon dioxide, helium, argon, chlorofluorocarbon gases, and mixtures of these gases.
  • the pressure of the gas may be in the range of 0.0001 to 10 atmospheres.
  • the mold contact step may be performed in an atmosphere containing a condensable gas (hereinafter referred to as condensable gas atmosphere).
  • condensable gas atmosphere refers to the gas that will be condensed into liquid by capillary force generated in the operation of filling the mold. More specifically, the condensable gas is condensed into liquid by capillary force generated when the gas, together with (part of) the coating film 105, fills the recesses of the fine pattern of the mold 104 and the gap between the mold 104 and the substrate 102 or the adhesion layer 101.
  • the condensable gas is in the form of gas in the atmosphere before the photocurable composition 103 (to which the pattern will be transferred) is brought into contact with the mold 104 in the mold contact step (Fig. 1C (C-1)).
  • the gas having filled the recesses of the fine pattern is turned into liquid, thereby removing air bubbles. Consequently, the coating film of the photocurable composition can satisfactorily fill the recesses of the mold.
  • the condensable gas may be dissolved in the photocurable composition 103.
  • the boiling point of the condensable gas is lower than or equal to the temperature of the atmosphere, and may be in the range of -10°C to 23°C, such as 10°C to 23°C.
  • the mold 104 can be satisfactorily filled.
  • the vapor pressure of the condensable gas at the temperature of the atmosphere in the mold contact step is lower than or equal to the pressure the mold 104 applies in the mold contact step and may be in the range of 0.1 MPa to 0.4 MPa.
  • the mold 104 can be satisfactorily filled. If the vapor pressure is higher than 0.4 MPa at ambient temperature, air bubbles are unlikely to be removed as expected. In contrast, if the vapor pressure is lower than 0.1 MPa at ambient temperature, decompression is required. This makes complicated the imprinting apparatus used for forming a patterned film by the method of the present embodiment.
  • the ambient temperature in the mold contact step may be in the range of, but is not limited to, 20°C to 25°C.
  • FCs fluorocarbons
  • CFCs chlorofluorocarbons
  • HFCs hydrofluorocarbons
  • HCFCs hydrochlorofluorocarbons
  • CHF 2 CH 2 CF 3 , HFC-245fa, PFP 1,1,1,3,3-pentafluoropropane
  • HFEs hydrofluoro ethers
  • pentafluoroethyl methyl ether CF 3 CF 2 OCH 3 , HFE-245mc
  • Condensable gases may be used singly or in combination.
  • the condensable gas may be a mixture of a condensable gas and a non-condensable gas, such as air, nitrogen, carbon dioxide, helium, or argon.
  • Helium is suitable as the non-condensable gas to be mixed with the condensable gas from the viewpoint of satisfactorily filling the mold.
  • Helium can pass through the mold 104.
  • the gas (condensable gas and helium) together with (part of) the coating film 105, has filled the recesses of the fine pattern of the mold 104, helium passes through the mold 104, while the condensable gas turns into liquid.
  • the use of helium as the non-condensable gas is effective in satisfactorily filling the mold.
  • At least either position of the mold or the substrate or workpiece is adjusted so that alignment marks 106 on the mold and alignment marks 107 on the substrate are aligned with each other, if necessary, as shown in Fig. 1D.
  • the contact portion between the photocurable composition 103 and the mold 104 is irradiated with light through the mold 104 with the mold and the substrate aligned in the alignment step (4), as shown in Fig. 1E.
  • the coating film 105 filling the fine pattern of the mold 104 is irradiated with light 107 through the mold 104 (Fig. 1E (e-1)).
  • the portions of the coating film 105 filling the fine pattern of the mold 104 are cured into a cured product 109 by the irradiation light 108 (Fig. 1E (e-2)).
  • the light for irradiating the photocurable composition 103 that forms the coating film 105 filling the fine pattern of the mold 104 is appropriately selected according to the wavelength to which the photocurable composition 103 is sensitive.
  • Examples of such light include ultraviolet light having a wavelength of 150 nm to 400 nm, X-ray radiation, and electron beams.
  • ultraviolet light is more suitable as the light for irradiating the photocurable composition 103 (irradiation light 108). This is because many of the commercially available curing agents (photopolymerization initiators) are sensitive to ultraviolet light.
  • Light sources that emit ultraviolet light include high-pressure mercury-vapor lamps, ultrahigh-pressure mercury-vapor lamps, low-pressure mercury-vapor lamps, Deep-UV lamps, carbon arc lamps, chemical lamps, metal halide lamps, xenon lamps, KrF excimer lasers, ArF excimer lasers, and F 2 excimer lasers.
  • An ultrahigh-pressure mercury-vapor lamp is advantageous.
  • the number of light sources may be one or more.
  • the coating film 105 filling the fine pattern of the mold 104 may be irradiated in part or entirety.
  • the irradiation may be performed over the entire region of the substrate 102 intermittently several times or continuously.
  • region A may be irradiated in a first stage of irradiation
  • region B different from region A, may be irradiated in a second stage of the irradiation.
  • the amount of exposure of the photocurable composition 103 may be 90 mJ/cm 2 or less.
  • a small amount of exposure is desirable, 30 mJ/cm 2 or less is optimal.
  • a small amount of exposure mentioned herein implies 76 mJ/cm 2 or less.
  • the mold 104 is removed from the cured product 109.
  • a cured product pattern 110 having a specific shape has been formed on the substrate 102.
  • the cured product 109 is separated from the mold 104, as shown in Fig. 1F, to obtain a cured product pattern 110 formed in the irradiation step (5) and having a pattern reverse to the fine pattern of the mold 104.
  • the condensable gas evaporates as the pressure at the interface between the cured product 109 and the mold 104 is reduced by removing the mold 104 from the cured product 109. This is effective in removing the mold 104 from the cured product 109 with a low force.
  • the mold 104 may be moved so as to go away from the substrate 102 (workpiece) fixed, or the substrate 102 may be moved so as to go away from the mold 104 fixed.
  • the mold 104 and the substrate 102 may be drawn in the opposite directions so as to separate from each other.
  • the above-described process including the steps of (1) to (6) forms in a desired position a cured film having a desired relief pattern derived from the relief pattern in the mold 104.
  • the resulting cured film may be used as, for example, an optical member such as a Fresnel lens or a diffraction grating, or a member in the optical member.
  • the optical member includes at least the substrate 102 and the cured product pattern 110 on the substrate 102.
  • a repeating unit (shot) including steps (1) to (6) may be repeated several times for the same substrate 102.
  • a cured product pattern 110 can be formed which has a plurality of desired patterns derived from the relief pattern of the mold 104 in a desired region.
  • the cured product pattern 110 formed through the mold-releasing step (6) has a specific pattern, and a portion of which may lie in a region other than the region in which the pattern should be formed (hereinafter such a portion of the cured product pattern may be referred to as an unwanted portion).
  • the unwanted portion of the cured product pattern and the portion of the adhesion layer 101 underlying the unwanted portion are removed as shown in Fig. 1G. Consequently, a cured product pattern 111 having a desired relief pattern structure (derived from the relief pattern of the mold 104) is formed.
  • the unwanted portion of the cured product pattern 110 and the portion of the adhesion layer 101 underlying the unwanted portion may be removed by, for example, etching.
  • the surface of the substrate 102 is exposed in the recesses of the cured product pattern 110.
  • any technique may be applied without particular limitation.
  • dry etching may be applied.
  • a known dry etching apparatus can be used.
  • the source gas used for this dry etching can be selected, according to the elemental composition of the cured film 110 to be etched.
  • the source gas examples include halogen-containing gases, such as CF 4 , C 2 F 6 , C 3 F 8 , CCl 2 F 2 , CCl 4 , CBrF 3 , BCl 3 , PCl 3 , SF 6 , and Cl 2 ; oxygen-containing gases, such as O 2 , CO, and CO 2 ; inert gases, such as He, N 2 , and Ar; and other gases such as H 2 and NH 3 .
  • halogen-containing gases such as CF 4 , C 2 F 6 , C 3 F 8 , CCl 2 F 2 , CCl 4 , CBrF 3 , BCl 3 , PCl 3 , SF 6 , and Cl 2
  • oxygen-containing gases such as O 2 , CO, and CO 2
  • inert gases such as He, N 2 , and Ar
  • other gases such as H 2 and NH 3 .
  • a mixed gas of these gases may be used.
  • the cured product pattern 111 having a desired relief pattern structure (derived from the relief pattern of the mold 104) in a desired position is formed, and, thus, an article having the cured product pattern 111 is completed. If the substrate 102 is processed using the cured product pattern 111, a processing step (Step of (8)) is performed on the substrate as described below.
  • the resulting cured product pattern 111 may be used as an optical member, such as a diffraction grating or a polarizer (or a part of such an optical member) for an optical component.
  • the optical component includes at least the substrate 102 and the cured product pattern 111 on the substrate 102.
  • the cured product pattern 111 having a relief pattern structure formed by the method of the present embodiment may be used as an interlayer insulating film of electronic components, such as semiconductor devices.
  • the cured product pattern 111 may also be used as a resist film in a process for manufacturing semiconductor devices.
  • the semiconductor devices include, but are not limited to, LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM.
  • the cured product pattern 111 is used as a resist film, portions (regions denoted by reference numeral 112 in Fig. 1G) of the substrate that have been exposed by the step (7) of removing unwanted portions are subjected to etching or ion implantation.
  • the cured product pattern 111 functions as an etching mask.
  • the substrate 102 may be provided with electronic members.
  • a circuit structure 113 (Fig. 1H) is formed on the substrate 102 according to the structure of the cured product pattern 111.
  • a circuit board used for a semiconductor device or the like is produced.
  • the resulting circuit board may be connected to a control mechanism for the circuit board for producing an electronic apparatus, such as a display, a camera, or a medical apparatus.
  • the cured product pattern 111 may be used as a resist film for etching or ion implantation in a process for manufacturing an optical component or a device component, such as a flow channel structure of microfluidics and a patterned medium structure.
  • the cured product pattern 111 may be used as a mask (resist film) for etching or ion implantation in a process for manufacturing an optical component.
  • the cured product pattern 111 may be used for producing an imprinting mold by etching a quartz substrate that is the substrate 102.
  • the quartz substrate may be directly etched using the cured product pattern 111 as a mask.
  • a hard mask material layer may be etched using the cured product pattern 111 as a mask, and the quartz substrate is etched using the thus transferred pattern of the hard mask material as a mask.
  • a second cured product of a second curable material may be formed in the recesses of the cured product pattern 111, and the second cured product may be used as a mask for etching the quartz substrate.
  • dry etching For etching exposed portions of the substrate using the cured product pattern 111 as a mask, dry etching can be applied.
  • dry etching a known dry etching apparatus may be used.
  • the source gas used for this dry etching can be selected, according to the elemental composition of the cured film to be etched.
  • the source gas examples include halogen-containing gases, such as CF 4 , CHF 3 , C 2 F 6 , C 3 F 8 , C 4 F 8 , CCl 2 F 2 , CCl 4 , CBrF 3 , BCl 3 , PCl 3 , SF 6 , and Cl 2 ; oxygen-containing gases, such as O 2 , CO, and CO 2 ; inert gases, such as He, N 2 , and Ar; and other gases such as H 2 and NH 3 .
  • fluorine-containing gases such as CF 4 , CHF 3 , C 2 F 6 , C 3 F 8 , C 4 F 8 , CCl 2 F 2 , CBrF 3 , and SF 6 .
  • the photocurable composition used in the present embodiment is highly resistant to dry etching using these fluorine-containing gases. A mixed gas of these gases may be used.
  • the processing of the substrate 102 using the cured product pattern 111 is performed by etching or ion implantation.
  • the method for processing the substrate 102 is however not limited to these techniques.
  • the substrate 102 with the cured product pattern 111 thereon may be subjected to plating or the like.
  • the cured product pattern 111 may finally be removed from the substrate, or may be left as a member of the device.
  • the following compound (A), compound (B) and solvent (C) were mixed to prepare an adhesion layer composition.
  • solvent (C) propylene glycol monomethyl ether acetate (produced by Tokyo Chemical Industry) was used.
  • an adhesion layer composition containing compound (A) and (B) with a total content of 0.5% by weight was prepared for each combination of compound (A) and compound (B) shown in Table 1, there were prepared an adhesion layer composition containing compound (A) and (B) with a total content of 0.5% by weight, and an adhesion layer composition containing compounds (A) and (B) with a total content of 5.0% by weight.
  • Adhesion layer composition was filtered through a polytetrafluoroethylene filter of 0.2 ⁇ m in pore size. Adhesion layer compositions 1 to 17 shown in Table 1 were thus prepared. (Compound (A))
  • A-1) Dipentaerythritol hexaacrylate (Light Acrylate DPE-6A, produced by Kyoeisha Chemical)
  • A-2) Dipentaerythritol tetraacrylate (Light Acrylate PE-4A, produced by Kyoeisha Chemical)
  • A-3) Trimethylolpropane triacrylate (Biscoat #295, produced by Osaka Organic Chemical Industry)
  • A-4) Tricyclodecanedimethanol diacrylate (A-DCP, produced by Shin-Nakamura Chemical) (Compound (B))
  • B-1 Pentaerythritol tetrakis(3-mercaptopropionate) (produced by Tokyo Chemical Industry)
  • B-2) Trimethylolpropane tris(3-mercaptopropionate) (produced by Tokyo Chemical Industry)
  • B-3) Pentaerythritol tetrakis(3-mercaptobutyrate)
  • Karenz MT PE-1 produced by Showa Denko
  • B-4 1,3,5-Tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione
  • Karenz MT NR-1 1,10-Decanedithiol (produced by Tokyo Chemical Industry)
  • component (E) as a polymerizable compound and component (F) as a photopolymerization initiator were mixed, and the mixture was filtered through an ultrahigh molecular weight polyethylene filter of 0.2 ⁇ m in pore size to yield photocurable composition (p-1).
  • Each of the adhesion layer compositions 1 to 17 with a total compound content of 5.0% by weight was applied to a silicon wafer by spin coating at 3000 rpm for 30 s. Then, the coating of the composition was heated on a hot plate to yield an adhesion layer. The coatings of compositions 1 to 7, 14 and 15 were heated at 220°C for 10 minutes, and the coatings of compositions 8 to 13 and 16 and 17 were heated at 160°C for 120 minutes.
  • the surface of the adhesion layer formed in the above described operation (1) was wiped with a wiper Bemcot (manufactured by Asahi Kasei) soaked with acetone for examining the curability of the adhesion layer composition.
  • the curability was rated as A; when at least part of the adhesion layer was dissolved or separated, the curability was rated as B.
  • Each of the adhesion layer compositions 1 to 17 with a total compound content of 0.5% by weight was applied to a silicon wafer by spin coating at 3000 rpm for 30 s. Then, the coating of the adhesion layer composition was heated on a hot plate to yield an adhesion layer. The coatings of compositions 1 to 7, 14 and 15 were heated at 220°C for 10 minutes, and the coatings of compositions 8 to 13 and 16 and 17 were heated at 160°C for 120 minutes. Thus adhesion layers having a thickness of 10 nm or less were formed.
  • photocurable composition (p-1) Onto the silicon wafer on which the adhesion layer had been formed in the above-described operation (1), 2 ⁇ L of photocurable composition (p-1) was dropped. Then, the photocurable composition (p-1) was covered with a 1 mm thick quartz glass having a pattern so as to fill a region of 35 mm ⁇ 25 mm.
  • the photocurable composition was irradiated for 200 s through the quartz glass with light that was emitted from a UV light source with an ultrahigh-pressure mercury-vapor lamp and passed through an interference filter.
  • the photocurable composition (p-1) was cured into a cured film.
  • the interference filter was VPF-25C-10-15-31300 (manufactured by Sigmakoki), and the irradiation light was ultraviolet light having a single wavelength of 313 ⁇ 5 nm and an illuminance of 1.0 mW/cm 2 .
  • Examples 1 to 16 each used an adhesion layer made of any one of the adhesion layer compositions 1 to 6. Comparative Example 1 did not use an adhesion layer, and Comparative Example 2 used a composition containing a monomer having a bifunctional ethylenic unsaturated group and a bifunctional thiol group.

Abstract

An adhesion layer composition contains a compound (A) having at least three ethylenic unsaturated groups in the molecule thereof, and a compound (B) having at least two thiol groups in the molecule thereof.

Description

ADHESION LAYER COMPOSITION, METHODS FOR FORMING ADHESION LAYER AND CURED PRODUCT PATTERN, AND METHODS FOR MANUFACTURING OPTICAL COMPONENT, CIRCUIT BOARD, IMPRINTING MOLD AND DEVICE COMPONENT
The present invention relates to an adhesion layer composition, methods for forming an adhesion layer and a cured product, and methods for manufacturing an optical component, a circuit board, an imprinting mold and a device component.
Miniaturization is increasingly demanded for semiconductor devices, microelectromechanical systems (MEMS) and the like, and, in these fields, photo-nanoimprinting techniques are attracting attention.
In the photo-nanoimprinting technique, a mold having a fine relief pattern in the surface thereof is pressed against a substrate to which a photocurable composition (resist) has been applied, and the photocurable composition is cured in this state. Thus, the relief pattern of the mold is transferred to the cured film of the photocurable composition, thereby forming a pattern on the substrate. The photo-nanoimprinting technique enables a fine structure of the order of several nanometers to be formed on a substrate.
In a photo-nanoimprinting technique, first, a photocurable composition is applied to the region on a substrate to which a pattern will be formed (disposing step). Subsequently, the photocurable composition is shaped in a mold having a pattern (mold contact step). Then, the photocurable composition is cured by being irradiated with light (irradiation step), and separated from the mold (mold-releasing step). Through these steps, a resin pattern (photo-cured film) having a specific shape is formed on the substrate.
In the mold-releasing step, adhesion between the photocurable composition and the substrate is important. If the adhesion between the photocurable composition and the substrate is low, part of the photo-cured product of the photocurable composition can remain undesirably in the mold and be removed from the substrate together with the mold when the mold is removed. This is a cause of a defect of pattern separation.
A technique is devised for increasing the adhesion between the photocurable composition and the substrate by forming an adhesion layer between the photocurable composition and the substrate (PTL 1).
In the technique of PTL 1, the adhesion layer is formed using an organic compound having in the molecule thereof a thiol group and a reactive functional group capable of forming a chemical bond with an organic compound.
Japanese Patent Laid-Open No. 2013-153084
The adhesion layer is required to have a high adhesion to the photocurable composition and the substrate, and, in addition, to have a high strength so as to be a strong film. The organic compound disclosed in PTL 1 is used for binding the thiol group to the substrate, and for binding the reactive functional group to the photocurable composition. The adhesion between the photocurable composition and the substrate is thus increased, whereas the strength of the adhesion layer itself is insufficient. An adhesion layer having a low strength can be broken in the mold-releasing step and cause a defect of pattern separation.
It is known that the strength of a cured film of a curable composition can be increased by adding a crosslinking agent to the curable composition. Unfortunately, if the strength of an adhesion layer is increased by adding a known crosslinking agent, the number of the functional groups capable of binding the photocurable composition to the substrate is reduced, and consequently the adhesion decreases.
Accordingly, the present invention provides an adhesion layer composition that can reduce a defect of pattern separation.
According to an aspect of the present invention, there is provided an adhesion layer composition containing a compound (A) having at least three ethylenic unsaturated groups in the molecule thereof and a compound (B) having at least two thiol groups in the molecule thereof.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawing.
Fig. 1A is a schematic sectional view illustrating a method for forming a cured product pattern according to an embodiment of the present invention. Fig. 1B is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention. Fig. 1C is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention. Fig. 1D is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention. Fig. 1E is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention. Fig. 1F is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention. Fig. 1G is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention. Fig. 1H is a schematic sectional view illustrating a method for forming a cured product pattern according to the embodiment of the present invention.
Embodiments of the present invention will now be described in detail. The present invention is not limited to the following embodiments and includes any modification or change that can be made within the scope and spirit of the invention on the basis of the knowledge of those skilled in the art.
The adhesion layer composition 100 (hereinafter referred to as the composition 100 in some cases) disclosed herein is intended to form an adhesion layer 101 between a substrate 102 and a photocurable composition 103 (hereinafter referred to as the composition 103 in some cases). The adhesion layer composition 100 contains a compound (A) having at least three ethylenic unsaturated groups and a compound (B) having at least two thiol groups capable of binding to the ethylenic unsaturated groups.
The phrase "functional group (of Y) capable of binding to X" is a functional group that can form a chemical bond such as covalent bond, an ionic bond, a hydrogen bond, or a bond by intermolecular force between X and Y. Advantageously, the "functional group (of Y) capable of binding to X" used herein is a functional group capable of forming a covalent bond between X and Y. Such a functional group can form a strong bond between X and Y.
The adhesion layer composition 100 of an embodiment of the present invention may be suitable for the case where it is applied onto a substrate 102 and cured to form a cured product. A composite including the adhesion layer 101 formed by curing the adhesion layer composition 100 and a substrate 102 is suitably used as a substrate on which a photocurable composition 103 will be disposed for producing a photo-cured product 109. The adhesion layer composition 100 can be used as an adhesion layer composition used for imprinting, and is, in particularly, useful as an adhesion layer composition used for photo-nanoimprinting.
The constituents of the adhesion layer composition 100 will now be described in detail.
Compound (A)
Compound (A) used in the present embodiment has at least three ethylenic unsaturated groups in the molecule thereof.
The ethylenic unsaturated group of compound (A) is a functional group that will bind to the photocurable composition 103. More specifically, compound (A) forms a covalent bond with a polymerizable compound in the photocurable composition 103 by a chain transfer reaction with radicals produced in the photocurable composition 103 in an irradiation step described later. Thus a chemical bond is formed between the adhesion layer and the photocurable composition 103. Consequently, the adhesion between the adhesion layer 101 and the cured product 109 of the photocurable composition 103 is increased.
The ethylenic unsaturated groups of compound (A) are not particularly limited as long as they are functional groups that can bind to the photocurable composition 103, and can be selected according to the constituents and contents thereof of the photocurable composition 103. For example, a functional group that can easily form a covalent bond with the photocurable composition 103 is advantageous as an ethylenic unsaturated group of compound (A). Such a functional group can form a strong bond between the adhesion layer 101 and the photocurable composition 103.
The ethylenic unsaturated group may be vinyl, allyl, (meth)acryloyl, or the like. If the photocurable composition 103 contains a (meth)acryloyl compound as a polymerizable compound, it is advantageous that the ethylenic unsaturated group be (meth)acryloyl, which forms easily a covalent bond with the photocurable compound. A (meth)acryloyl group mentioned herein refers to the acryloyl group or the methacryloyl group.
Also, part of the ethylenic unsaturated groups of compound (A) will form a sulfide bond with the thiol group of compound (B) by a thiol-ene reaction in an adhesion layer forming step described later. Hence, the ethylenic unsaturated group of compound (A) is a functional group that can bind to compound (B).
Also, part of the ethylenic unsaturated groups of compound (A) will form covalent bonds with the ethylenic unsaturated groups of other molecules of compound (A) by radical chain transfer reaction among the molecules.
Because of the three or more ethylenic unsaturated groups of compound (A), compound (A) has the function of forming a cross link between compound (B) and the photocurable composition 103 or the photo-cured product 109 of the photocurable composition 103 by the mechanism described above. Compound (A) also has the function of forming a cross link between two molecules thereof or a cross link with compound (B).
By forming a chemical bond between compound (A) and compound (B) so as to form a structure having a cross link between the compounds that form the adhesion layer 101, the amount of free molecules of compounds (A) and (B) not binding to the substrate 102 can be reduced. Thus, the strength of the adhesion layer 101 can be increased.
If an unreacted free molecules of compound (A) or compound (B) is present in the adhesion layer 101, such a portion will dissolve into the photocurable composition 103 applied onto the adhesion layer 101 in the step of applying the photocurable composition 103. Consequently, the photocurable composition 103 is varied in constitution and, accordingly, the properties thereof are changed in such a manner, for example, that there occurs a defect such as separation of the pattern of the cured product 109 of the photocurable composition 103.
On the other hand, the use of the adhesion layer composition 100 of the present embodiment considerably reduces the amount of free molecules of compound (A) or (B) not binding to the substrate 102 in the adhesion layer 101 in comparison with the known techniques. Thus, the dissolution of compound (A) or (B) into the photocurable composition 103 in the step of applying the composition 103 can be significantly reduced. Consequently, a defect such as separation of the pattern of the photo-cured product 109 can be prevented.
From the viewpoint of producing the effects described above to a higher extent, a larger number of ethylenic unsaturated groups are desired in compound (A). Compound (A) having a larger number of ethylenic unsaturated groups forms a more three-dimensional cross-linked structure, accordingly increasing the strength of the adhesion layer 101. Also, such compound (A) facilitates the formation of chemical bonds among molecules thereof, between compound (A) and compound (B), and between compound (A) and the photocurable composition 103. Therefore the number of ethylenic unsaturated groups of compound (A) is at least three, and desirably four or more, more desirably six or more.
The ethylenic unsaturated group may be vinyl or acrylic group, and the compounds having at least three vinyl or acrylic groups that can be used as compound (A) include, but are not limited to, 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane, 1,2,4-trivinylcyclohexane, triallylamine, triallyl 1,3,5-benzenetricarboxylate, triallyl citrate, triallyl cyanurate, triallyl isocyanurate, triallyl phosphorate, tetraallyloxyethane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane, and pentaerythritol triallyl ether.
Compound (A) may be a monofunctional (meth)acrylic compound having a (meth)acryloyl group, and examples thereof include, but are not limited to, 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, 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, pentyl (meth)acrylate, 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,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.
Compound (A) may be a polyfunctional (meth)acrylic compound having two (meth)acryloyl groups, and examples thereof include, but are not limited to, trimethylolpropane di(meth)acrylate, dimethyloltricyclodecane diacrylate, 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, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-adamantane dimethanol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, bis(hydroxymethyl)tricyclodecane di(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.
Compound (A) may be a polyfunctional (meth)acrylic compound having at least three (meth)acryloyl groups, and examples thereof include, but are not limited to, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate, EO/PO-modified trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tris(acryloyloxy)isocyanurate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.
In the above-cited compounds, (meth)acrylate refers to an acrylate or the methacrylate containing the same alcohol residue as the acrylate. EO represents ethylene oxide, and EO-modified compound Z is a compound in which the (meth)acrylic acid residue and alcohol residue of compound Z are bound to each other with an ethylene oxide block structure therebetween. PO represents propylene oxide, and PO-modified compound W is a compound in which the (meth)acrylic acid residue and alcohol residue of compound Z are bound to each other with a propylene oxide block structure therebetween.
Compound (B)
Compound (B) used in the present embodiment has at least two thiol groups in the molecule thereof.
The thiol group of compound (B) is a functional group that will bind to the substrate 102. The thiol group of compound (B) forms any one of chemical bonds, such as a covalent bond, a hydrogen bond or a bond by intermolecular force, with a functional group present at the surface of the substrate 102 in the adhesion layer forming step described later. More specifically, the adhesion layer 101 and the substrate 102 are bound to each other with a sulfur atom therebetween. Consequently, the adhesion between the adhesion layer 101 and the substrate 102 is increased.
The thiol groups of compound (B) will form sulfide bonds with part of the ethylenic unsaturated groups of compound (A) by a thiol-ene reaction in the adhesion layer forming step described later. Hence, the thiol group of compound (B) is a functional group that will bind to compound (A).
Because of the two or more thiol groups of compound (B), compound (B) has the function of forming a cross link between the substrate 102 and compound (A) or between the molecules of compound (A) by the mechanism described above.
By forming a chemical bond between compound (A) and compound (B) so as to form a structure having a cross link between the compounds that form the adhesion layer 101, the amount of free molecules of compounds (A) and (B) not binding to the substrate 102 can be reduced. Thus, the dissolution of compound (A) or (B) into the photocurable composition 103 in the step of applying the photocurable composition 103 can be significantly reduced, and a defect such as separation of the pattern of the photo-cured product 109 can be prevented.
From the viewpoint of producing the effects described above to a higher extent, a larger number of thiol groups are desired, and advantageously, compound (B) has three or more thiol groups. Compound (B) having three or more thiol groups forms a more three-dimensional cross-linked structure, accordingly increasing the strength of the adhesion layer 101. Also, such compound (B) facilitates the formation of chemical bonds with compound (A) and with the substrate 102. As the number of thiol groups become larger, compound (B) is more effective in the above-described point of view. More advantageously, compound (B) has four or more thiol groups.
Examples of the compound having at least two thiol groups that can be used as compound (B) include, but are not limited to, bifunctional thiol compounds, such as 1,4-bis(3-mercaptobutyryloxy)butane; trifunctional thiol compounds, such as 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate), and pentaerythritol tris(3-mercaptobutyrate); and tetrafunctional thiol compounds, such as pentaerythritol tetrakis(mercaptoacetate), pentaerythritol tetrakis(3-mercaptobutyrate), and pentaerythritol tetrakis(3-mercaptopropionate).
Compound (A) and compound (B) each may be composed of a single compound or a combination of a plurality of compounds.
In addition, it is advantageous that compound (A) have three or more ethylenic unsaturated groups, or that compound (B) have three or more thiol groups. Such compound (A) and compound (B) can easily form a three-dimensional cross-linked structure, accordingly increasing the strength of the adhesion layer 101 that is formed by curing the adhesion layer composition 100.
If the total number of thiol groups in the adhesion layer composition 100 is excessively large relative to the total number of ethylenic unsaturated groups, all the ethylenic unsaturated groups of compound (A) can be used for the reaction with the thiol groups of compound (B) in the adhesion layer forming step. Consequently, the surface of the adhesion layer 101 opposite the substrate 102 becomes short of ethylenic unsaturated groups. The ethylenic unsaturated group is the functional group intended to bind to the photocurable composition 103 applied on the surface of the adhesion layer 101 opposite the substrate 102. Therefore the adhesion between the adhesion layer 101 and the photocurable composition 103 becomes insufficient.
In contrast, if the total number of thiol groups in the adhesion layer composition 100 is excessively small relative to the total number of ethylenic unsaturated groups, the probability of forming cross links between compound (A) and compound (B) is reduced, and the amount of free compound (A) not binding to the substrate 102 increases.
Accordingly, it is desirable that the proportions of compound (A) and compound (B) satisfy the following. In the adhesion layer composition 100, the functional group number ratio α/β of the total number α of ethylenic unsaturated groups to the total number β of the thiol groups is in the range of 1/9 to 9. More desirably, the α/β ratio is in the range of 1/2 to 9, and particularly in the range of 1 to 4. By controlling the functional group number ratio in the adhesion layer composition 100 in such a range, the adhesion of the adhesion layer 101 to the photocurable composition 103 can be increased while the strength of the adhesion layer 101 is increased.
The total number α of the ethylenic unsaturated groups of compound (A) in the adhesion layer composition 100 can be calculated using equation (1): α = a × nA × NA. In equation (1), a represents the number of ethylenic unsaturated groups in the molecule of compound (A); nA represents the amount of compound (A) by mole in the adhesion layer composition 100; and NA represents the Avogadro constant.
Similarly, the total number β of the thiol groups of compound (A) in the adhesion layer composition 100 can be calculated using equation (2): β = b × nB × NA. In equation (2), b represents the number of thiol groups in the molecule of compound (B); nB represents the amount of compound (B) by mole in the adhesion layer composition 100; and NA represents the Avogadro constant.
The total content of compounds (A) and (B) in the adhesion layer composition 100 may be determined according to the viscosity of the adhesion layer composition 100, the thickness of the adhesion layer, and the like. The total content of compounds (A) and (B) may be in the range of 0.01% to 10% by weight, desirably in the range of 0.1% to 7% by weight, relative to the total weight of the composition 100.
Volatile Solvent (C)
The adhesion layer composition 100 according to the present embodiment contains a volatile solvent (C) (hereinafter simply referred to as solvent (C)). Solvent (C) in the adhesion layer composition 100 reduces the viscosity of the adhesion layer composition 100. Consequently, the adhesion layer composition 100 can be easily applied onto the substrate 102.
Solvent (C) is not particularly limited as long as it can dissolve compound (A) and compound (B), and desirably has a boiling point of 80°C to 200°C under normal pressure. More desirably, solvent (C) is an organic solvent having at least one structure of an ester structure, a ketone structure, a hydroxy group, and an ether structure. Such a solvent is superior in dissolving compound (A) and compound (B) and in wetting the substrate 102.
Examples of the solvent that can be used as solvent (C) include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, cyclohexanone, 2-heptanone, γ-butyrolactone, and ethyl lactate. These may be used singly or in combination. From the viewpoint of easily applying the adhesion layer composition, propylene glycol monomethyl ether acetate or a mixed solvent thereof is advantageous.
The content of solvent (C) in the adhesion layer composition 100 is appropriately determined according to the viscosities of compound (A) and compound (B), the ease of application of the composition, and the thickness of the adhesion layer 101, and the like. The content of solvent (C) in the adhesion layer composition 100 may be 70% by mass or more, and is desirably 90% by mass or more, more desirably 95% by mass or more, relative to the total mass of the adhesion layer composition 100. If the content of solvent (C) in the adhesion layer composition 100 is less than 70% by mass, the composition might not have satisfactory characteristics for being applied. The upper limit of the solvent (C) content in the adhesion layer composition 100 is not particularly limited, and is desirably 99.9% by mass.
Thermal Polymerization Initiator (D)
The adhesion layer composition 100 of the present embodiment may further contain a thermal polymerization initiator (D). Thermal polymerization initiator (D) in the adhesion layer composition 100 promotes polymerization reaction, thereby reducing the amount of unreacted compound (A). Consequently, it is suppressed that the unreacted compound (A) dissolves in the photocurable composition 103 (described later) applied onto the adhesion layer and adversely affects the photocurable composition 103. Examples of thermal polymerization initiator (D) include azo compounds and organic peroxides. These compounds may be used singly or in combination.
Exemplary azo compounds include azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyronitrile), 2,2'-azobis-2-methylbutyronitrile, 1,1'-azobis(1-cyclohexanecarbonitrile), 2,2'-azobis(methylisobutyrate), 2,2'-azobis(2-amidinopropane)dihydrochloride, and 2,2'-azobis(N-butyl-2-methylpropionamide).
Exemplary organic peroxides include hydroperoxide, dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxybenzoate, benzoyl peroxide, peroxy ketal, ketone peroxide, t-butyl peroxyacetate, 2,2-bis(t-butyldioxy)butane, t-butylbenzoyl peroxide, butyl 4,4-bis[(t-butyl)peroxy]pentanate, di-t-hexyl peroxide, t-butyl α-cumyl peroxide, di-t-butyl peroxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, and t-butyl hydroperoxide.
Among these advantageous are compounds whose decomposition temperature is 100°C or more, and examples of such a compound include 2,2'-azobis(N-butyl-2-methylpropionamide), t-butyl peroxyacetate, 2,2-bis(t-butyldioxy)butane, t-butylbenzoyl peroxide, butyl 4,4-bis[(t-butyl)peroxy]pentanate, di-t-hexyl peroxide, t-butyl α-cumyl peroxide, di-t-butyl peroxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, and t-butyl hydroperoxide.
Other Constituents (X)
The adhesion layer composition 100 of the present embodiment may further contain additives (X) in addition to compounds (A) and (B), solvent (C) and thermal polymerization initiator (D), according to the use thereof within a range in which the intended effects of the present invention are produced. Such additives include a surfactant, a crosslinking agent, a polymer component, an antioxidant, and a polymerization inhibitor.
Viscosity of Adhesion Layer Composition
The viscosity of the adhesion layer composition 100 of the present embodiment depends on the constituents and contents of the constituents, such as compound (A), compound (B), solvent (C), and thermal polymerization initiator (D), and is desirably in the range of 0.5 mPa*s to 20 mPa*s at 23°C. Desirably, it is in the range of 1 mPa*s to 10 mPa*s, such as 1 mPa*s to 5 mPa*s.
The adhesion layer composition 100 having a viscosity of 20 mPa*s or less can be easily applied to the substrate 102, and accordingly, the thickness of the coating of the adhesion layer composition 100 on the substrate 102 can be easily adjusted.
Impurities in Adhesion Layer Composition
Desirably, the impurity content in the adhesion layer composition 100 is as low as possible. Impurities mentioned herein refer to constituents other than compound (A), compound (B), solvent (C), thermal polymerization initiator (D) and other additives (X).
It is therefore desirable that the adhesion layer composition 100 have been purified. For example, filtration through a filter is advantageous for purification.
For filtration through a filter, more specifically, the mixture of the constituents may be filtered through a filter having a pore size in the range of 0.001 μm to 5.0 μm. This filtration may be performed in a plurality of steps or repeated several times. The filtrate may be further filtered. A plurality of filters having different pore sizes may be used. The filter may be made of, but not limited to, polyethylene, polypropylene, fluororesin, or nylon.
Impurities such as particulate matter can be removed from the adhesion layer composition 100 by such purification. Thus, unexpected defects can be prevented which particulate matter or other impurities may cause in the adhesion layer formed by applying the adhesion layer composition 100.
If the adhesion layer composition 100 of the present embodiment is used for manufacturing a circuit board used in semiconductor devices, it is desirable to avoid the contamination of the composition 100 with metallic impurities containing a metal atom as much as possible in order to prevent the metallic impurities from interfering with the operation of the resulting circuit board. In this instance, it is desirable to reduce the concentration of metallic impurities in the adhesion layer composition 100 to 10 ppm or less, more desirably 100 ppb or less.
Photocurable Composition
The photocurable composition 103 used with the adhesion layer 101 formed of the adhesion layer composition 100 of the present embodiment generally contains a polymerizable compound (component (E)) and a photopolymerization initiator (component (F)).
Component (E): Polymerizable Compound
Component (E) is a polymerizable compound. The polymerizable compound mentioned used herein is a compound that reacts with a polymerizing factor, such as radicals, produced from the photopolymerization initiator (component (F)) and forms a polymer film by chain reaction (polymerization reaction).
The polymerizable compound, or component (E), may be composed of a single polymerizable compound or a combination of a plurality of polymerizable compounds.
The polymerizable compound may be a radically polymerizable compound. The radically polymerizable compound may have one or more acryloyl group or methacryloyl group, and hence may be a (meth)acrylic compound.
Thus, the polymerizable compound, or component (E), desirably contains a (meth)acrylic compound. Also, it is more desirable that the (meth)acrylic compound be the main constituent of component (E). Optimally, component (E) is a (meth)acrylic compound. When a (meth)acrylic compound is the main constituent of component (E), the (meth)acrylic compound accounts for 90% by weight or more of component (E).
If the radically polymerizable compound is a combination of a plurality of compounds each having at least one acryloyl group or methacryloyl group, it is advantageous that radically polymerizable compound contain a monofunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate monomer. By combining a monofunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate monomer, a strong cured film can be formed.
Examples of the monofunctional (meth)acrylic compound having one acryloyl group or methacryloyl group include, but are not limited to, 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, 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, pentyl (meth)acrylate, 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,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.
Some monofunctional (meth)acrylic compounds are commercially available, and examples thereof include, but are not limited to, Aronix series M101, M102, M110, M111, M113, M117, M5700, TO-1317, M120, M150 and M156 (each produced by Toagosei); MEDOL 10, MIBDOL 10, CHDOL 10, MMDOL 30, MEDOL 30, MIBDOL 30, CHDOL 30, LA, IBXA, 2-MTA, HPA, and Biscoat series #150, #155, #158, #190, #192, #193, #220, #2000, #2100 and #2150 (each produced by Osaka Organic Chemical Industry); Light Acrylates BO-A, EC-A, DMP-A, THF-A, HOP-A, HOA-MPE, HOA-MPL, PO-A, P-200A, NP-4EA and NP-8EA, and epoxy ester M-600A (each produced by Kyoeisha Chemical); KAYARAD TC110S, R-564 and R-128H (each produced by Nippon Kayaku); NK esters AMP-10G and AMP-20G (each produced by Shin-Nakamura Chemical); FA-511A, 512A and 513A (each produced by Hitachi Chemical); PHE, CEA, PHE-2, PHE-4, BR-31, BR-31M and BR-32 (each produced by Dai-ichi Kogyo Seiyaku); VP (produced by BASF); and ACMO, DMAA and DMAPAA (each produced by Kohjin).
Examples of the polyfunctional (meth)acrylic compound having two or more acryloyl or methacryloyl groups include, but are not limited to, 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, dimethyloltricyclodecane diacrylate, 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, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-adamantanedimethanol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, 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.
The polyfunctional (meth)acrylic compound is commercially available, and example thereof include, but are not limited to, Yupimer UV SA1002 and Yupimer UV SA2007 (each produced by Mitsubishi Chemical); Biscoat series #195, #230, #215, #260, #335HP, #295, #300, #360, #700, GPT and 3PA (each produced by Osaka Organic Chemical Industry); Light Acrylates 4EG-A, 9EG-A, NP-A, DCP-A, BP-4EA, BP-4PA, TMP-A, PE-3A, PE-4A and DPE-6A (each produce by Kyoeisha Chemical); A-DCP, A-HD-N, A-NOD-N and A-DOD-N (each produced by Shin-Nakamura Chemical); KAYARAD PET-30, TMPTA, R-604, DPHA, DPCA-20, -30, -60 and -120, HX-620, D-310, and D-330 (each produced by Nippon Kayaku); Aronix series M208, M210, M215, M220, M240, M305, M309, M310, M315, M325 and M400 (each produced by Toagosei); and Ripoxy VR-77, Ripoxy VR-60 and Ripoxy VR-90 (each produced by Showa Denko).
In the above-cited compounds, (meth)acrylate refers to an acrylate or the methacrylate containing the same alcohol residue as the acrylate. Also, a (meth)acryloyl group mentioned herein refers to the acryloyl group or the methacryloyl group. EO represents ethylene oxide, and PO represents propylene oxide.
Component (F): Photopolymerization Initiator
Component (F) is a photopolymerization initiator. The photopolymerization initiator used herein is a compound capable of sensing light having a specific wavelength to produce a polymerizing factor (radicals) Specifically, the photopolymerization initiator is a radical generator that produces radicals with light (radiations, such as infrared radiation, visible light radiation, ultraviolet radiation, far ultraviolet radiation, X-ray radiation, charged particle radiation such as electron beams, and other radiation). More specifically, the photopolymerization initiator generates radicals with light having, for example, a wavelength in the range of 150 nm to 400 nm.
Component (F) may be composed of a single photopolymerization initiator or a combination of a plurality of photopolymerization initiators.
Exemplary radical generators include, but are not limited to, substituted or unsubstituted 2,4,5-triarylimidazole dimers, 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 and benzophenone derivatives, such as N,N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, and 4,4'-diaminobenzophenone; α-aminoaromatic ketone derivatives, such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one; quinones, such as 2-ethylanthraquinone, phenanthrenequinone, 2-t-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, and 2,3-dimethylanthraquinone; benzoin ether derivatives, such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzoin and benzoin derivatives, such as methylbenzoin, ethylbenzoin, and propylbenzoin; benzyl derivatives such as benzyl dimethyl ketal; acridine derivatives, such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; N-phenylglycine and N-phenylglycine derivatives; acetophenone and acetophenone derivatives, such as 3-methylacetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, and 2,2-dimethoxy-2-phenylacetophenone; thioxanthone and thioxanthone derivatives, such as 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; oxime ester derivatives, such as 1,2-octanedione, 1-[4-(phenylthio)phenyl-,2-(o-benzoyloxime)], ethanone,1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,1-(O-acetyloxime); and xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-one, and 2-hydroxy-2-methyl-1-phenylpropane-1-one.
The radical generator may be commercially available, and examples thereof include, but are not limited to, Irgacure series 184, 369, 651, 500, 819, 907, 784 and 2959, CGI-1700, -1750 and -1850, CG24-61, Darocur series l116 and 1173, Lucirin TPO, LR 8893, and LR 8970 (each produced by BASF); and Ubecryl P36 (produced by UCB).
The proportion of component (F) to component (E) in the photocurable composition 103 may be in the range of 0.01% to 10% by weight, and is desirably in the range of 0.1% to 7% by weight.
When the proportion of component (F) is 0.01% by weight or more relative to the total weight of components (E) in the photocurable composition 103, the photocurable composition 103 can be cured in a shorter time, thus increasing reaction efficiency. Also, when the proportion of component (F) is 10.0% by weight or less relative to the total weight of component (E), the resulting cured film tends to be prevented from being degraded in mechanical strength.
Other Additives (G)
The photocurable composition 103 may further contain additives (G) in addition to component (E) and component (F) according to the use of the composition within a range in which the intended effects of the present invention are produced. Such additives (G) include a sensitizer, a hydrogen donor, an internal releasing agent, a surfactant, an antioxidant, a solvent, a polymer component, and a polymerization initiator other than component (F).
The sensitizer is optionally added to promote the polymerization reaction or increase reaction conversion rate. The sensitizer may be a sensitizing dye.
The sensitizing dye is a compound that is excited by absorbing light having a specific wavelength and interacts with component (F). The phrase "interacts with" mentioned here implies that, for example, energy or electrons transfer from the excited sensitizing dye to component (F).
Examples of the sensitizing dye 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, camphorquinone derivatives, acridine dyes, thiopyrylium salt-based dyes, merocyanine dyes, quinoline dyes, styryl quinoline dyes, ketocoumarin dyes, thioxanthene dyes, xanthene dyes, oxonol dyes, cyanine dyes, rhodamine dyes, and pyrylium salt-based dyes.
These sensitizing dyes may be used singly or in combination.
The hydrogen donor is a compound that can react with an initiator radical generated from component (F) or a chain end radical, thereby producing a more reactive radical. It is advantageous to add a hydrogen donor when component (F) is a photoradical generator.
Examples of the hydrogen donor include, but are not limited to, amine compounds, such as n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthiourea, s-benzylisothiuronium-p-toluene sulfonate, triethylamine, diethylaminoethyl methacrylate, triethylenetetramine, 4,4'-bis(dialkylamino)benzophenone, ethyl N,N-dimethylaminobenzate, isoamyl N,N-dimethylaminobenzoate, pentyl 4-(dimethylamino)benzoate, triethanolamine, and N-phenylglycine; and mercapto compounds, such as 2-mercapto-N-phenylbenzoimidazole and mercaptopropionic acid esters.
These hydrogen donors may be used singly or in combination.
The hydrogen donor may have a function as a sensitizer.
If the photocurable composition 103 contains a sensitizer or a hydrogen donor as other additives (G), the proportion of each additive may be in the range of 0.1% to 20% by weight relative to the total weight of component (E). Desirably, it is in the range of 0.1% to 5.0% by weight, and more desirably in the range of 0.2% to 2.0% by weight. When the proportion of the sensitizer is 0.1% by weight or more relative to the total weight of component (E), polymerization can be promoted more effectively. Also, by controlling the proportion of the sensitizer or the hydrogen donor to 5.0% by weight or less, the photocurable composition 103 can be cured into a polymer film having a sufficiently large molecular weight. Also, these constituents in such a proportion can be miscible with the photocurable composition 103 and prevent the degradation of the storage stability of the photocurable composition 103.
An internal releasing agent may be added to the photocurable composition 103 in order to reduce the interfacial bonding strength between a mold 104 and the photo-cured product 109 of the photocurable composition 103, that is, to reduce the force for removing the mold in a mold-releasing step described later. The internal releasing agent mentioned herein is a releasing agent that has been added to the photocurable composition 103 in advance of applying the photocurable composition 103. The internal releasing agent may be composed of a single material or a combination of a plurality of materials.
The internal releasing agent may be a surfactant, such as a silicone surfactant, a fluorosurfactant, or a hydrocarbon surfactant. In the present embodiment, the internal releasing agent is not polymerizable.
The fluorosurfactant may be a polyalkylene oxide (such as polyethylene oxide or polypropylene oxide) adduct of an alcohol having a perfluoroalkyl group, or a polyalkylene oxide (such as polyethylene oxide or polypropylene oxide) adduct of perfluoropolyether. The fluorosurfactant may have a hydroxy, alkoxy, alkyl, amino or thiol group or the like in a part (for example, a terminal group) of the molecule.
The fluorosurfactant may be a commercially available product. Examples of the commercially available fluorosurfactant include, but are not limited to, Megafac series F-444, TF-2066, TF-2067 and TF-2068 (each produced by DIC); Fluorad series FC-430 and FC-431 (each produced by Sumitomo 3M); Surflon S-382 (produced by AGC); EFTOP EF-122A, 122B, 122C, EF-121, EF-126, EF-127 and MF-100 (each produced by Tochem Products); PF-636, PF-6320, PF-656 and PF-6520 (each produced by OMNOVA Solutions); Unidyne series DS-401, DS-403 and DS-451 (each produced by Daikin Industries); and Ftergent series 250, 251, 222F and 208G (each produced by Neos).
The internal releasing agent may be a hydrocarbon surfactant.
The hydrocarbon surfactant may be an alkyl alcohol polyalkylene oxide adduct produced by adding an alkylene oxide having a carbon number of 2 to 4 to an alkyl alcohol having a carbon number of 1 to 50.
Examples of the alkyl alcohol polyalkylene oxide adduct include methyl alcohol ethylene oxide adduct, decyl alcohol ethylene oxide adduct, lauryl alcohol ethylene oxide adduct, cetyl alcohol ethylene oxide adduct, stearyl alcohol ethylene oxide adduct, and stearyl alcohol ethylene oxide/propylene oxide adduct. The terminal group of the alkyl alcohol polyalkylene oxide adduct is not limited to the hydroxy group, which is formed by simply adding a polyalkylene oxide to an alkyl alcohol. The hydroxy group may be substituted with a polar functional group, such as carboxy, amino, pyridyl, thiol, or silanol, or a hydrophobic functional group, such as alkyl or alkoxy.
A commercially available alkyl alcohol polyalkylene oxide adduct may be used. Examples of the commercially available alkyl alcohol polyalkylene oxide adduct include, but are not limited to, polyoxyethylene methyl ethers (methyl alcohol ethylene oxide adducts), such as BLAUNON series MP-400, MP-550 and MP-1000 (each produced by Aoki Oil Industrial); polyoxyethylene decyl ethers (decyl alcohol ethylene oxide adducts), such as FINESURF series D-1303, D-1305, D-1307 and D-1310 (each produced by Aoki Oil Industrial); polyoxyethylene lauryl ethers (lauryl alcohol ethylene oxide adduct), such as BLAUNON EL-1505 (produced by Aoki Oil Industrial); polyoxyethylene cetyl ethers (cetyl alcohol ethylene oxide adducts), such as BLAUNON series CH-305 and CH-310 (each produced by Aoki Oil Industrial); polyoxyethylene stearyl ethers (stearyl alcohol ethylene oxide adducts), such as BLAUNON series SR-705, SR-707, SR-715, SR-720, SR-730 and SR-750 (each produced by Aoki Oil Industrial); random copolymer type polyoxyethylene/polyoxypropylene stearyl ethers, such as BLAUNON series SA-50/50 1000R and SA-30/70 2000R (each produced by Aoki Oil Industrial); polyoxyethylene methyl ethers, such as Pluriol A760E (produced by BASF); and polyoxyethylene alkyl ethers, such as EMULGEN series (produced by Kao).
Among the above-cited hydrocarbon surfactants, alkyl alcohol polyalkylene oxide adducts, particularly, long chain alkyl alcohol polyalkylene oxide adducts, are advantageous as the internal releasing agent. When the photocurable composition 103 contains an internal releasing agent as one of the other additives (G), the proportion of the internal releasing agent may be in the range of 0.001% to 10% by weight relative to the total weight of the polymerizable compound or component (E). Desirably, it is in the range of 0.01% to 7% by weight, and more desirably in the range of 0.05% to 5% by weight. When the proportion of the internal releasing agent is at least in the range of 0.001% to 10% by weight, the mold can be easily removed, and the photocurable composition can satisfactorily fill the mold.
Temperature for Preparing Photocurable Composition
For preparing the photocurable composition 103, at least components (E) and (F) are mixed and dissolved in each other at a predetermined temperature, for example, in the range of 0°C to 100°C. The same applies to the case of containing other additives (G).
Viscosity of Photocurable Composition
The mixture of the constituents of the photocurable composition 103 other than solvent may have a viscosity in the range of 1 mPa*s to 100 mPa*s at 23°C. Desirably, it is in the range of 1 mPa*s to 50 mPa*s, such as 1 mPa*s to 20 mPa*s.
The photocurable composition 103 having a viscosity of 100 mPa*s or less can fill the recesses of the fine pattern of the mold 104 without taking a long time when the photocurable composition 103 is brought into contact with the mold 104. The use of such a photocurable composition 103 enables photo-nanoimprinting with a high productivity. Also, filling failure that causes a defect in the resulting pattern is unlikely to occur.
The photocurable composition 103 having a viscosity of 1 mPa*s or more can be easily applied uniformly on the substrate 102, and is unlikely to flow out of the mold as the photocurable composition 103 is brought into contact with the mold.
Surface Tension of Photocurable Composition
The mixture of the constituents of the photocurable composition 103 other than solvent may have a surface tension in the range of 5 mN/m to 70 mN/m at 23°C. Desirably, it is in the range of 7 mN/m to 35 mN/m, such as 10 mN/m to 32 mN/m. The photocurable composition 103 having a surface tension of 5 mN/m or more can fill the recesses of the fine pattern of the mold 104 without taking a long time as the photocurable composition 103 is brought into contact with the mold 104.
Also, when the photocurable composition 103 has a surface tension of 70 mN/m or less, the cured film 109 formed by irradiating the photocurable composition 103 with light has a smooth surface.
Impurities in Photocurable Composition
Desirably, the impurity content in the photocurable composition 103 is as low as possible.
It is therefore desirable that the photocurable composition 103 have been purified as with the adhesion layer composition 100. For example, filtration through a filter is advantageous for purification.
For filtration through a filter, more specifically, the mixture of the above-described constituents may be filtered through a filter having a pore size in the range of 0.001 μm to 5.0 μm. This filtration may be performed in a plurality of steps or repeated several times. The filtrate may be further filtered. A plurality of filters having different pore sizes may be used. The filter may be made of, but not limited to, polyethylene, polypropylene, fluororesin, or nylon.
Impurities such as particulate matter can be removed from the photocurable composition 103 by such purification. Thus, unexpected pattern defects can be prevented which result from unevenness caused by particulate matter or other impurities in the cured film 109 formed by curing the photocurable composition 103.
If the photocurable composition 103 is used for manufacturing a circuit board used in semiconductor devices, it is desirable to avoid the contamination with metallic impurities containing a metal atom as much as possible in order to prevent the metallic impurities from interfering with the operation of the resulting circuit board. In this instance, it is desirable to reduce the concentration of metallic impurities in the photocurable composition 103 to 10 ppm or less, more desirably 100 ppb or less.
Formation of Cured Product Pattern
A method for forming a cured product pattern (cured film having a pattern) according to an embodiment will now be described. Figs. 1A to 1H are schematic sectional views illustrating a method for forming a cured product pattern according to the present embodiment.
In the present embodiment, the method for forming a cured product pattern includes:
(1) a first step of forming an adhesion layer on a substrate, using the adhesion layer composition of an embodiment of the invention (adhesion layer forming step);
(2) a second step of disposing a photocurable composition on the substrate (disposing step);
(3) a third step of bringing the photocurable composition into contact with a mold (mold contact step);
(5) a fourth step of irradiating the photocurable composition with light with the mold in contact therewith (irradiation step); and
(6) a fifth step of removing the mold from the cured film formed in the fourth step (mold-releasing step).
The method may include the following step between the third and the fourth step:
(4) a step of aligning the mold with the substrate (alignment step).
This method for forming a cured product pattern incorporates a photo-nanoimprinting technique.
The cured product pattern formed by the method of the present embodiment may have a line width in the range of 1 nm to 10 mm, advantageously in the range of 10 nm to 100 μm. In general, methods for forming nanometer scale (1 nm to 100 nm) patterns (having a relief structure) using light are called photo-nanoimprinting.
The steps of the method will now be described.
Adhesion Layer Forming Step (1)
In the adhesion layer forming step, an adhesion layer 101 mainly containing a polymer is formed on a substrate 102, as shown in Fig. 1A, using the above-described adhesion layer composition 100.
The substrate 102 is a workpiece to which the photocurable composition 103 will be disposed (applied) and is typically silicon wafer. Since the silicon wafer has silanol groups and hydroxy groups at the surface thereof. Accordingly, it is expected that chemical bonds are easily formed between the substrate 102 and the thiol groups of compound (B) by heating. Thus, the adhesion layer 101 and the substrate 102 are bound to each other with sulfur atoms therebetween.
The substrate 102 is however not limited to silicon wafer. The substrate 102 may be arbitrarily selected from among substrates used for semiconductor devices, such as substrates made of aluminum, titanium-tungsten alloy, aluminum-silicon alloy, aluminum-copper-silicon alloy, silicon oxide, or silicon nitride. Alternatively, the substrate 102 may be a substrate provided thereon with one or more films, such as a spin-on-glass film, an organic film, a metal film, an oxide film, and a nitride film. Desirably, the substrate 102 has hydroxy groups at the surface thereof. This is because the hydroxy groups at the surface of the substrate 102 facilitates the formation by heating of chemical bonds between the substrate 102 and the thiol groups of compound (B).
The adhesion layer composition 100 may be applied onto the substrate 102 by, for example, an ink jet method, dip coating, air knife coating, curtain coating, wire bar coating, gravure coating, extrusion coating, spin coating, or a slit scan method. From the viewpoint of easy application, particularly of forming a uniform thickness, spin coating is advantageous.
After the application of the adhesion layer composition 100 onto the substrate 102, solvent (C) is removed from the adhesion layer composition 100 by drying. At this time, it is desirable to perform reactions between compound (B) and the substrate 102 and between compound (A) and compound (B) simultaneously with the removal of solvent (C). Thus, chemical bonds are formed between the substrate 102 and the adhesion layer 101 and between compounds (A) and (B) in the adhesion layer 101. The chemical bond between compound (A) and compound (B) is a sulfide bond formed by a thiol-ene reaction between the ethylenic unsaturated group of compound (A) and the thiol group of compound (B).
For those reactions, the substrate 102 and the adhesion layer composition 100 are desirably heated. The heating temperature for the reactions is set depending on the reactivity between compound (B) and the substrate 102, the reactivity between compound and compound (B), and the boiling points of compound (A), compound (B) and solvent (C), and other factors. The heating temperature may be in the range of 70°C to 250°C, and is desirably in the range of 100°C to 220°C, such as 140°C to 220°C. The drying of solvent (C), the reaction between the substrate 102 and compound (B), and the crosslinking reaction between compound (A) and compound (B) may be performed at the same temperature or different temperatures. Hence, these operation and reactions may be performed at one time or one after another.
The thickness of the adhesion layer 101 formed by applying the adhesion layer composition 100 onto the substrate 102 depends on use, and may be, for example, in the range of 0.1 nm to 100 nm. Desirably, it is in the range of 0.5 nm to 60 nm, such as 1 nm to 10 nm.
When the adhesion layer 101 is formed by applying the adhesion layer composition 100 onto the substrate 102, a multilayer adhesion layer 101 may be formed by repeating the application of the adhesion layer composition 100 in such a manner that another adhesion layer is formed on a previously formed adhesion layer. Desirably, the resulting adhesion layer 101 is as flat as possible. The surface roughness of the adhesion layer is desirably 1 nm or less.
A composite including the substrate 102 and the adhesion layer 101 formed on the substrate 102 are formed as below. The adhesion layer 101 contains sulfide bonds formed by a thiol-ene reaction between the ethylenic unsaturated group of compound (A) and the thiol group of compound (B). Also, the adhesion layer 101 and the substrate 102 are bound to each other by the thiol group of compound (B), hence binding together with a sulfur atom therebetween.
The adhesion layer 101, or polymer layer, contains sulfur atoms deriving from compound (B), and many of the sulfur atoms are present at the surface of the adhesion layer 101 adjacent to the substrate 102. This is because the thiol group of compound (B) is a functional group capable of binding to the substrate 102 and, accordingly, the molecules of compound (B) are likely to be distributed close to the substrate 102 by the adhesion layer forming step. Then, compound (B) binding to the substrate 102 reacts with compound (A). Thus, many of the sulfur atoms deriving from compound (B) are present at the surface of the adhesion layer 101 adjacent to the substrate 102. At the surface of the adhesion layer 101 opposite the substrate 102, ethylenic unsaturated groups deriving from compound (A) are present. The ethylenic unsaturated groups enable the adhesion layer 101 to be bound to the photocurable composition 103 through the steps of (2) to (5).
Disposing Step (2)
In the disposing step, the photocurable composition 103 is applied onto the adhesion layer 101 on the substrate 102, and thus a coating film of the composition 103 is disposed on the substrate 102, as shown in Fig. 1B.
In the present embodiment, the photocurable composition 103 may be applied by, for example, an ink jet method, dip coating, air knife coating, curtain coating, a wire bar coating, gravure coating, extrusion coating, spin coating, or a slit scan method. For a photo-nanoimprinting method, an ink jet method is particularly suitable. The thickness of the coating film of the photocurable composition (to which a pattern will be transferred) depends on use, and may be, for example, in the range of 0.01 μm to 100.0 μm.
Mold Contact Step (3)
Subsequently, the coating film of the photocurable composition 103 formed in the preceding disposing step is brought into contact with a mold 104 having an original pattern to be transferred, as shown in Fig. 1C (c-1). Thus the recesses of the original fine pattern in the surface of the mold 104 are filled with (part of) the photocurable composition 103, so that a coating film 105 filling the fine pattern of the mold 104 is formed (Fig. 1C (c-2)).
Advantageously, the mold 104 is made of an optically transparent material in view of the subsequent irradiation step. Examples of the material of the mold 104 include glass, quartz, optically transparent resins, such as polymethyl methacrylate (PMMA) and polycarbonate, transparent metal films formed by vapor deposition, soft films of polydimethylsiloxane or the like, photo-cured films, and metal films. If an optically transparent resin is used as the material of the mold 104, the optically transparent resin is a material insoluble in any constituent of the photocurable composition 103. Quartz is particularly suitable as the material of the mold 104 because it has a small thermal expansion coefficient and is accordingly unlikely to deform the pattern.
The fine pattern in the surface of the mold 104 may have a height in the range of 4 nm to 200 nm and each trace of the pattern may have an aspect ratio in the range of 1 to 10.
The mold 104 may be surface-treated before the mold contact step so that the mold 104 can be easily removed from the photocurable composition 103. For the surface treatment, a releasing agent may be applied to the surface of the mold 104.
Examples of the releasing agent to be applied to the surface of the mold 104 include silicone releasing agents, fluorine-based releasing agents, hydrocarbon releasing agents, polyethylene-based releasing agents, polypropylene-based releasing agents, paraffin releasing agents, montanic releasing agents, and carnauba releasing agents. Commercially available releasing agents that are the type of being applied, such as Optool DSX produced by Daikin Industries, can be advantageously used. Those releasing agents may be used singly or in combination. Fluorine-based and hydrocarbon releasing agents are particularly advantageous.
When the photocurable composition 103 is brought into contact with the mold 104 as shown in Fig. 1C (c-1), the pressure (mold pressure) applied to the photocurable composition 103 is not particularly limited, but is typically in the range of 0 MPa to 100 MPa. The pressure is desirably in the range of 0 MPa to 50 MPa, and more desirably in the range of 0 MPa to 30 MPa, such as 0 MPa to 20 MPa.
The period of time for which the mold 104 is kept in contact with the photocurable composition 103 is not particularly limited. It is typically in the range of 0.1 s to 600 s, and is desirably in the range of 0.1 s to 300 s, more desirably in the range of 0.1 s to 180 s, such as 0.1 s to 120 s.
Although the mold contact step can be performed in any atmosphere of atmospheres of air, reduced pressure and an inert gas, it is advantageous that the mold contact step is performed in an atmosphere of reduced pressure or an inert gas, from the viewpoint of preventing oxygen or moisture from affecting the curing reaction. Inert gases that can be used in this step include nitrogen, carbon dioxide, helium, argon, chlorofluorocarbon gases, and mixtures of these gases. When the mold contact step is performed in an atmosphere of a specific gas, including the case of air, the pressure of the gas may be in the range of 0.0001 to 10 atmospheres.
The mold contact step may be performed in an atmosphere containing a condensable gas (hereinafter referred to as condensable gas atmosphere). The condensable gas mentioned herein refers to the gas that will be condensed into liquid by capillary force generated in the operation of filling the mold. More specifically, the condensable gas is condensed into liquid by capillary force generated when the gas, together with (part of) the coating film 105, fills the recesses of the fine pattern of the mold 104 and the gap between the mold 104 and the substrate 102 or the adhesion layer 101. The condensable gas is in the form of gas in the atmosphere before the photocurable composition 103 (to which the pattern will be transferred) is brought into contact with the mold 104 in the mold contact step (Fig. 1C (C-1)).
In the mold contact step performed in a condensable gas atmosphere, the gas having filled the recesses of the fine pattern is turned into liquid, thereby removing air bubbles. Consequently, the coating film of the photocurable composition can satisfactorily fill the recesses of the mold. The condensable gas may be dissolved in the photocurable composition 103.
The boiling point of the condensable gas is lower than or equal to the temperature of the atmosphere, and may be in the range of -10°C to 23°C, such as 10°C to 23°C. When the condensable gas has a boiling point in this range, the mold 104 can be satisfactorily filled.
The vapor pressure of the condensable gas at the temperature of the atmosphere in the mold contact step is lower than or equal to the pressure the mold 104 applies in the mold contact step and may be in the range of 0.1 MPa to 0.4 MPa. When the condensable gas has a vapor pressure in this range, the mold 104 can be satisfactorily filled. If the vapor pressure is higher than 0.4 MPa at ambient temperature, air bubbles are unlikely to be removed as expected. In contrast, if the vapor pressure is lower than 0.1 MPa at ambient temperature, decompression is required. This makes complicated the imprinting apparatus used for forming a patterned film by the method of the present embodiment.
The ambient temperature in the mold contact step may be in the range of, but is not limited to, 20°C to 25°C.
Examples of the condensable gas include fluorocarbons (FCs) including chlorofluorocarbons (CFCs), such as trichlorofluoromethane; hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs), such as 1,1,1,3,3-pentafluoropropane (CHF2CH2CF3, HFC-245fa, PFP); and hydrofluoro ethers (HFEs), such as pentafluoroethyl methyl ether (CF3CF2OCH3, HFE-245mc).
From the viewpoint of satisfactorily filling the mold at a temperature of 20°C to 25°C in the atmosphere in the mold contact step, advantageous are 1,1,1,3,3-pentafluoropropane (vapor pressure at 23°C: 0.14 MPa, boiling point: 15°C), trichlorofluoromethane (vapor pressure at 23°C: 0.1056 MPa, boiling point: 24°C) and pentafluoroethyl methyl ether. Particularly advantageous is 1,1,1,3,3-pentafluoropropane because of having high safety.
Condensable gases may be used singly or in combination. The condensable gas may be a mixture of a condensable gas and a non-condensable gas, such as air, nitrogen, carbon dioxide, helium, or argon. Helium is suitable as the non-condensable gas to be mixed with the condensable gas from the viewpoint of satisfactorily filling the mold. Helium can pass through the mold 104. When the gas (condensable gas and helium), together with (part of) the coating film 105, has filled the recesses of the fine pattern of the mold 104, helium passes through the mold 104, while the condensable gas turns into liquid. Thus, the use of helium as the non-condensable gas is effective in satisfactorily filling the mold.
Alignment Step (4)
In the subsequent step, at least either position of the mold or the substrate or workpiece is adjusted so that alignment marks 106 on the mold and alignment marks 107 on the substrate are aligned with each other, if necessary, as shown in Fig. 1D.
Irradiation Step (5)
Subsequently, the contact portion between the photocurable composition 103 and the mold 104 is irradiated with light through the mold 104 with the mold and the substrate aligned in the alignment step (4), as shown in Fig. 1E. More specifically, the coating film 105 filling the fine pattern of the mold 104 is irradiated with light 107 through the mold 104 (Fig. 1E (e-1)). Thus the portions of the coating film 105 filling the fine pattern of the mold 104 are cured into a cured product 109 by the irradiation light 108 (Fig. 1E (e-2)).
The light for irradiating the photocurable composition 103 that forms the coating film 105 filling the fine pattern of the mold 104 is appropriately selected according to the wavelength to which the photocurable composition 103 is sensitive. Examples of such light include ultraviolet light having a wavelength of 150 nm to 400 nm, X-ray radiation, and electron beams.
Among these, ultraviolet light is more suitable as the light for irradiating the photocurable composition 103 (irradiation light 108). This is because many of the commercially available curing agents (photopolymerization initiators) are sensitive to ultraviolet light. Light sources that emit ultraviolet light include high-pressure mercury-vapor lamps, ultrahigh-pressure mercury-vapor lamps, low-pressure mercury-vapor lamps, Deep-UV lamps, carbon arc lamps, chemical lamps, metal halide lamps, xenon lamps, KrF excimer lasers, ArF excimer lasers, and F2 excimer lasers. An ultrahigh-pressure mercury-vapor lamp is advantageous. The number of light sources may be one or more. The coating film 105 filling the fine pattern of the mold 104 may be irradiated in part or entirety.
The irradiation may be performed over the entire region of the substrate 102 intermittently several times or continuously. Alternatively, for example, region A may be irradiated in a first stage of irradiation, and region B, different from region A, may be irradiated in a second stage of the irradiation.
In the irradiation step, the amount of exposure of the photocurable composition 103 may be 90 mJ/cm2 or less. A small amount of exposure is desirable, 30 mJ/cm2 or less is optimal. A small amount of exposure mentioned herein implies 76 mJ/cm2 or less.
Mold-Releasing Step (6)
Subsequently, the mold 104 is removed from the cured product 109. At this time, a cured product pattern 110 having a specific shape has been formed on the substrate 102.
In the mold-releasing step, the cured product 109 is separated from the mold 104, as shown in Fig. 1F, to obtain a cured product pattern 110 formed in the irradiation step (5) and having a pattern reverse to the fine pattern of the mold 104.
In the case of performing the mold contact step in a condensable gas atmosphere, the condensable gas evaporates as the pressure at the interface between the cured product 109 and the mold 104 is reduced by removing the mold 104 from the cured product 109. This is effective in removing the mold 104 from the cured product 109 with a low force.
How to remove the mold 104 from the cured product 109, including the conditions for mold releasing, is not particularly limited as long as the cured product 109 is not physically damaged. For example, the mold 104 may be moved so as to go away from the substrate 102 (workpiece) fixed, or the substrate 102 may be moved so as to go away from the mold 104 fixed. Alternatively, the mold 104 and the substrate 102 may be drawn in the opposite directions so as to separate from each other.
The above-described process including the steps of (1) to (6) forms in a desired position a cured film having a desired relief pattern derived from the relief pattern in the mold 104. The resulting cured film may be used as, for example, an optical member such as a Fresnel lens or a diffraction grating, or a member in the optical member. In this instance, the optical member includes at least the substrate 102 and the cured product pattern 110 on the substrate 102.
In the method for forming a cured product pattern according to the present embodiment, a repeating unit (shot) including steps (1) to (6) may be repeated several times for the same substrate 102. By repeating the repeating unit (shot) including the steps of (1) to (6) several times, a cured product pattern 110 can be formed which has a plurality of desired patterns derived from the relief pattern of the mold 104 in a desired region.
Unwanted Portion Removal Step (7) of Removing Part of Cured Film
The cured product pattern 110 formed through the mold-releasing step (6) has a specific pattern, and a portion of which may lie in a region other than the region in which the pattern should be formed (hereinafter such a portion of the cured product pattern may be referred to as an unwanted portion). In this instance, the unwanted portion of the cured product pattern and the portion of the adhesion layer 101 underlying the unwanted portion are removed as shown in Fig. 1G. Consequently, a cured product pattern 111 having a desired relief pattern structure (derived from the relief pattern of the mold 104) is formed.
In this step, the unwanted portion of the cured product pattern 110 and the portion of the adhesion layer 101 underlying the unwanted portion may be removed by, for example, etching. Thus, the surface of the substrate 102 is exposed in the recesses of the cured product pattern 110.
For removing unwanted portions in the recesses of the cured product pattern 110 and the portions of the adhesion layer 101 underlying the unwanted portions by etching, any technique may be applied without particular limitation. For example, dry etching may be applied. For the dry etching, a known dry etching apparatus can be used. The source gas used for this dry etching can be selected, according to the elemental composition of the cured film 110 to be etched. Examples of the source gas include halogen-containing gases, such as CF4, C2F6, C3F8, CCl2F2, CCl4, CBrF3, BCl3, PCl3, SF6, and Cl2; oxygen-containing gases, such as O2, CO, and CO2; inert gases, such as He, N2, and Ar; and other gases such as H2 and NH3. A mixed gas of these gases may be used.
In the above-described process including the steps of (1) to (7), the cured product pattern 111 having a desired relief pattern structure (derived from the relief pattern of the mold 104) in a desired position is formed, and, thus, an article having the cured product pattern 111 is completed. If the substrate 102 is processed using the cured product pattern 111, a processing step (Step of (8)) is performed on the substrate as described below.
Alternatively, the resulting cured product pattern 111 may be used as an optical member, such as a diffraction grating or a polarizer (or a part of such an optical member) for an optical component. In this instance, the optical component includes at least the substrate 102 and the cured product pattern 111 on the substrate 102.
Substrate Processing Step (8)
The cured product pattern 111 having a relief pattern structure formed by the method of the present embodiment may be used as an interlayer insulating film of electronic components, such as semiconductor devices. The cured product pattern 111 may also be used as a resist film in a process for manufacturing semiconductor devices. Examples of the semiconductor devices include, but are not limited to, LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM.
If the cured product pattern 111 is used as a resist film, portions (regions denoted by reference numeral 112 in Fig. 1G) of the substrate that have been exposed by the step (7) of removing unwanted portions are subjected to etching or ion implantation. In this instance, the cured product pattern 111 functions as an etching mask. In addition, the substrate 102 may be provided with electronic members. Thus, a circuit structure 113 (Fig. 1H) is formed on the substrate 102 according to the structure of the cured product pattern 111. Thus, a circuit board used for a semiconductor device or the like is produced. The resulting circuit board may be connected to a control mechanism for the circuit board for producing an electronic apparatus, such as a display, a camera, or a medical apparatus.
Similarly, the cured product pattern 111 may be used as a resist film for etching or ion implantation in a process for manufacturing an optical component or a device component, such as a flow channel structure of microfluidics and a patterned medium structure.
Similarly, the cured product pattern 111 may be used as a mask (resist film) for etching or ion implantation in a process for manufacturing an optical component.
Alternatively, the cured product pattern 111 may be used for producing an imprinting mold by etching a quartz substrate that is the substrate 102. In this instance, the quartz substrate may be directly etched using the cured product pattern 111 as a mask. Alternatively, a hard mask material layer may be etched using the cured product pattern 111 as a mask, and the quartz substrate is etched using the thus transferred pattern of the hard mask material as a mask. A second cured product of a second curable material may be formed in the recesses of the cured product pattern 111, and the second cured product may be used as a mask for etching the quartz substrate.
For etching exposed portions of the substrate using the cured product pattern 111 as a mask, dry etching can be applied. For the dry etching, a known dry etching apparatus may be used. The source gas used for this dry etching can be selected, according to the elemental composition of the cured film to be etched. Examples of the source gas include halogen-containing gases, such as CF4, CHF3, C2F6, C3F8, C4F8, CCl2F2, CCl4, CBrF3, BCl3, PCl3, SF6, and Cl2; oxygen-containing gases, such as O2, CO, and CO2; inert gases, such as He, N2, and Ar; and other gases such as H2 and NH3. Advantageous are fluorine-containing gases, such as CF4, CHF3, C2F6, C3F8, C4F8, CCl2F2, CBrF3, and SF6. The photocurable composition used in the present embodiment is highly resistant to dry etching using these fluorine-containing gases. A mixed gas of these gases may be used.
In the above-described embodiment, the processing of the substrate 102 using the cured product pattern 111 is performed by etching or ion implantation. The method for processing the substrate 102 is however not limited to these techniques. For example, the substrate 102 with the cured product pattern 111 thereon may be subjected to plating or the like.
In a process for manufacturing a substrate provided with a circuit or an electronic component, the cured product pattern 111 may finally be removed from the substrate, or may be left as a member of the device.
The present invention will be further described in detail with reference to the following Examples. However, the invention is not limited to the disclosed Examples. In the following description, "part(s)" and "%" are on a mass basis unless otherwise specified.
Preparation of Adhesion Layer Composition
The following compound (A), compound (B) and solvent (C) were mixed to prepare an adhesion layer composition. As solvent (C), propylene glycol monomethyl ether acetate (produced by Tokyo Chemical Industry) was used. For each combination of compound (A) and compound (B) shown in Table 1, there were prepared an adhesion layer composition containing compound (A) and (B) with a total content of 0.5% by weight, and an adhesion layer composition containing compounds (A) and (B) with a total content of 5.0% by weight.
The resulting adhesion layer composition was filtered through a polytetrafluoroethylene filter of 0.2 μm in pore size. Adhesion layer compositions 1 to 17 shown in Table 1 were thus prepared.
(Compound (A))
(A-1): Dipentaerythritol hexaacrylate (Light Acrylate DPE-6A, produced by Kyoeisha Chemical)
(A-2): Dipentaerythritol tetraacrylate (Light Acrylate PE-4A, produced by Kyoeisha Chemical)
(A-3): Trimethylolpropane triacrylate (Biscoat #295, produced by Osaka Organic Chemical Industry)
(A-4): Tricyclodecanedimethanol diacrylate (A-DCP, produced by Shin-Nakamura Chemical)
(Compound (B))
(B-1): Pentaerythritol tetrakis(3-mercaptopropionate) (produced by Tokyo Chemical Industry)
(B-2): Trimethylolpropane tris(3-mercaptopropionate) (produced by Tokyo Chemical Industry)
(B-3): Pentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT PE-1, produced by Showa Denko)
(B-4): 1,3,5-Tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (Karenz MT NR-1, produced by Showa Denko)
(B-5) 1,10-Decanedithiol (produced by Tokyo Chemical Industry)
Figure JPOXMLDOC01-appb-T000001
Preparation of Photocurable Composition
The following component (E) as a polymerizable compound and component (F) as a photopolymerization initiator were mixed, and the mixture was filtered through an ultrahigh molecular weight polyethylene filter of 0.2 μm in pore size to yield photocurable composition (p-1).
[Component (E): Polymerizable Compounds] 100 parts by weight in total
(E-1): Tricyclodecanedimethanol diacrylate (A-DCP, produced by Shin-Nakamura Chemical), 25 parts by weight
(E-2): Benzyl acrylate (V #160, produced by Osaka Organic Chemical Industry)
[Component (F): Photopolymerization Initiator] 75 parts by weight
(F-1): Lucirin TPO (produced by BASF), 3 parts by weight
Curability of Adhesion Layer Composition
The curability of the adhesion layer compositions was examined.
(1) Formation of Adhesion Layer 1
Each of the adhesion layer compositions 1 to 17 with a total compound content of 5.0% by weight was applied to a silicon wafer by spin coating at 3000 rpm for 30 s. Then, the coating of the composition was heated on a hot plate to yield an adhesion layer. The coatings of compositions 1 to 7, 14 and 15 were heated at 220°C for 10 minutes, and the coatings of compositions 8 to 13 and 16 and 17 were heated at 160°C for 120 minutes.
(2) Evaluation of Curability
The surface of the adhesion layer formed in the above described operation (1) was wiped with a wiper Bemcot (manufactured by Asahi Kasei) soaked with acetone for examining the curability of the adhesion layer composition. When the adhesion layer was not dissolved or separated by this operation, the curability was rated as A; when at least part of the adhesion layer was dissolved or separated, the curability was rated as B.
The results are shown collectively in Table 2.
Evaluation of Adhesion
Subsequently, the adhesion between the substrate and the cured film of the photocurable composition was examined for each of the adhesion layer compositions rated as A in the above examination of curability.
(1) Formation of Adhesion Layer 2
Each of the adhesion layer compositions 1 to 17 with a total compound content of 0.5% by weight was applied to a silicon wafer by spin coating at 3000 rpm for 30 s. Then, the coating of the adhesion layer composition was heated on a hot plate to yield an adhesion layer. The coatings of compositions 1 to 7, 14 and 15 were heated at 220°C for 10 minutes, and the coatings of compositions 8 to 13 and 16 and 17 were heated at 160°C for 120 minutes. Thus adhesion layers having a thickness of 10 nm or less were formed.
(2) Curing of Photocurable Composition
Onto the silicon wafer on which the adhesion layer had been formed in the above-described operation (1), 2 μL of photocurable composition (p-1) was dropped. Then, the photocurable composition (p-1) was covered with a 1 mm thick quartz glass having a pattern so as to fill a region of 35 mm × 25 mm.
Subsequently, the photocurable composition was irradiated for 200 s through the quartz glass with light that was emitted from a UV light source with an ultrahigh-pressure mercury-vapor lamp and passed through an interference filter. Thus the photocurable composition (p-1) was cured into a cured film. The interference filter was VPF-25C-10-15-31300 (manufactured by Sigmakoki), and the irradiation light was ultraviolet light having a single wavelength of 313 ± 5 nm and an illuminance of 1.0 mW/cm2.
(3) Evaluation of Adhesion
After the irradiation, the quartz glass was forcibly removed, and the cured film was visually checked for separation from the substrate. Samples exhibited no separation in the entire region of 35 mm × 25 mm were determined to be good, and samples exhibited some separation in the region of 35 mm × 25 mm were determined to be bad.
The results are shown collectively in Table 2.
Figure JPOXMLDOC01-appb-T000002
Examples 1 to 16 each used an adhesion layer made of any one of the adhesion layer compositions 1 to 6. Comparative Example 1 did not use an adhesion layer, and Comparative Example 2 used a composition containing a monomer having a bifunctional ethylenic unsaturated group and a bifunctional thiol group.
For each of the adhesion layer compositions of Examples 1 to 16, both the curability and the adhesion between the substrate and the cured film were good. This suggests that the use of any of the adhesion layers of the Examples can provide a cured film exhibiting a high adhesion to the substrate that is unlikely to cause a defect of pattern separation.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2014-253531, filed December 15, 2014 and No. 2015-187477 filed September 24, 2015, which are hereby incorporated by reference herein in their entirety.

Claims (19)

  1. An adhesion layer composition containing:
    a compound (A) having at least three ethylenic unsaturated groups in the molecule thereof; and
    a compound (B) having at least two thiol groups in the molecule thereof.
  2. The adhesion layer composition according to Claim 1, further containing a volatile solvent.
  3. The adhesion layer composition according to Claim 2, wherein the volatile solvent content is in the range of 70% by mass to 99.9% by mass relative to the total mass of the adhesion layer composition.
  4. The adhesion layer composition according to any one of Claims 1 to 3, wherein the adhesion layer composition is free from a photopolymerization initiator.
  5. The adhesion layer composition according to any one of Claims 1 to 4, further containing a thermal polymerization initiator.
  6. The adhesion layer composition according to any one of Claims 1 to 5, wherein the ethylenic unsaturated group of the compound (A) is an acryloyl group or a methacryloyl group.
  7. The adhesion layer composition according to any one of Claims 1 to 6, wherein the adhesion layer composition is used for forming an adhesion layer between a substrate and a photocurable composition containing an acryloyl group or a methacryloyl group.
  8. The adhesion layer composition according to any one of Claims 1 to 7, wherein the compound (A) is at least one selected from the group consisting of dipentaerythritol hexaacrylate, pentaerythritol tetraacrylate, and trimethylolpropane triacrylate.
  9. The adhesion layer composition according to any one of Claims 1 to 8, wherein the compound (B) is at least one selected from the group consisting of pentaerythritol tetrakis(3-mercaptopropionate), trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), and 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione.
  10. A method for forming an adhesion layer, the method comprising:
    applying the adhesion layer composition as set forth in any one of Claims 1 to 9 onto a substrate; and
    heating the adhesion layer composition on the substrate, thereby curing the adhesion layer composition.
  11. A method for forming a cured product pattern, the method comprising:
    a first step of forming an adhesion layer by applying the adhesion layer composition as set forth in any one of Claims 1 to 9 onto a substrate;
    a second step of disposing a photocurable composition on the substrate having the adhesion layer;
    a third step of bringing the photocurable composition into contact with a mold having an original pattern to be transferred;
    a fourth step of irradiating the photocurable composition with light to form a cured product; and
    a fifth step of separating the cured product from the mold.
  12. The method according to Claim 11, wherein the substrate onto which the adhesion layer composition is applied in the first step has hydroxyl groups at the surface thereof.
  13. The method according to Claim 11 or 12, wherein the photocurable composition contains an ethylenic unsaturated group.
  14. The method according to any one of Claims 11 to 13, wherein the second step is performed in an atmosphere containing a condensable gas.
  15. A method for manufacturing an optical component, the method comprising forming a cured product pattern by the method as set forth in any one of Claims 11 to 14.
  16. A method for manufacturing a circuit board, the method comprising:
    forming a cured product pattern on a substrate by the method as set forth in any one of Claims 11 to 14; and
    performing etching or ion implantation on the substrate, using the cured product pattern as a mask.
  17. The method according to Claim 16, wherein the circuit board is used in a semiconductor device.
  18. A method for manufacturing an imprinting mold, the method comprising:
    forming a cured product pattern on a substrate by the method as set forth in any one of Claims 11 to 14; and
    etching the substrate using the cured product pattern as a mask.
  19. A device component comprising:
    a substrate;
    a cured product having a relief pattern on the substrate; and
    an organic layer between the substrate and the cured product, the organic layer containing sulfur atoms, large part of the sulfur atoms being present at the surface adjacent to the substrate of the organic layer.
PCT/JP2015/006106 2014-12-15 2015-12-08 Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component WO2016098314A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020177018766A KR101952058B1 (en) 2014-12-15 2015-12-08 Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2014-253531 2014-12-15
JP2014253531 2014-12-15
JP2015-187477 2015-09-24
JP2015187477A JP6704701B2 (en) 2014-12-15 2015-09-24 Adhesion layer forming composition, adhesion layer production method, cured product pattern production method, optical component production method, circuit board production method, imprint mold production method, and device component

Publications (1)

Publication Number Publication Date
WO2016098314A1 true WO2016098314A1 (en) 2016-06-23

Family

ID=56126222

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/006106 WO2016098314A1 (en) 2014-12-15 2015-12-08 Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component

Country Status (1)

Country Link
WO (1) WO2016098314A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200308329A1 (en) * 2018-03-23 2020-10-01 Kateeva, Inc. Compositions and techniques for forming organic thin films

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010182986A (en) * 2009-02-09 2010-08-19 Nof Corp Manufacturing method of substrate with metal pattern and the substrate
US20130032971A1 (en) * 2010-04-09 2013-02-07 Fujifilm Corporation Method for forming patterns and method for producing patterned substrates
JP2013153084A (en) * 2012-01-25 2013-08-08 Dainippon Printing Co Ltd Production method of pattern structure and base material for patterning used therein
US20140220353A1 (en) * 2011-10-07 2014-08-07 Fujifilm Corporation Underlay film composition for imprints and method of forming pattern and pattern formation method using the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010182986A (en) * 2009-02-09 2010-08-19 Nof Corp Manufacturing method of substrate with metal pattern and the substrate
US20130032971A1 (en) * 2010-04-09 2013-02-07 Fujifilm Corporation Method for forming patterns and method for producing patterned substrates
US20140220353A1 (en) * 2011-10-07 2014-08-07 Fujifilm Corporation Underlay film composition for imprints and method of forming pattern and pattern formation method using the same
JP2013153084A (en) * 2012-01-25 2013-08-08 Dainippon Printing Co Ltd Production method of pattern structure and base material for patterning used therein

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200308329A1 (en) * 2018-03-23 2020-10-01 Kateeva, Inc. Compositions and techniques for forming organic thin films
US11732074B2 (en) * 2018-03-23 2023-08-22 Kateeva, Inc. Compositions and techniques for forming organic thin films

Similar Documents

Publication Publication Date Title
US10073341B2 (en) Adhesion layer composition, method for forming film by nanoimprinting, methods for manufacturing optical component, circuit board and electronic apparatus
JP7086841B2 (en) Pattern forming method, processed circuit board manufacturing method, optical component manufacturing method, circuit board manufacturing method, electronic component manufacturing method, imprint mold manufacturing method
JP6806766B2 (en) Pattern forming method, processed circuit board manufacturing method, optical component manufacturing method, circuit board manufacturing method, electronic component manufacturing method, imprint mold manufacturing method
JP6983757B2 (en) Pattern formation method, processed circuit board manufacturing method, optical component manufacturing method, circuit board manufacturing method, electronic component manufacturing method, imprint mold manufacturing method
JP7094878B2 (en) Pattern formation method, processed substrate manufacturing method, optical component manufacturing method, quartz mold replica manufacturing method, semiconductor element manufacturing method
JP6961495B2 (en) Pattern formation method, processed circuit board manufacturing method, optical component manufacturing method, circuit board manufacturing method, electronic component manufacturing method, imprint mold manufacturing method
KR101952058B1 (en) Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component
JP6632340B2 (en) Adhesive layer forming composition, method for producing cured product pattern, method for producing optical component, method for producing circuit board, method for producing imprint mold, and device component
US10293543B2 (en) Method of producing a patterned film
WO2015170465A1 (en) Curable composition and cured product thereof, method for producing cured product, method for manufacturing optical component, method for manufacturing circuit board, and method for manufacturing electronic component
WO2016136181A1 (en) Patterning method, method for producing processed substrate, method for producing optical component, method for producing circuit board, and method for producing electronic component
JP6333050B2 (en) Compound, photocurable composition, cured product, method for producing film having pattern shape, method for producing optical component, method for producing circuit board, method for producing electronic component using the same
JP6324363B2 (en) Photocurable composition for imprint, method for producing film using the same, method for producing optical component, method for producing circuit board, method for producing electronic component
JP6624808B2 (en) Photocurable composition, method for producing cured product pattern using the same, method for producing optical component, method for producing circuit board
KR20190117761A (en) Pattern formation method, imprint apparatus and curable composition using optical nanoimprint technology
US10593547B2 (en) Photocurable composition, and methods using the same for forming cured product pattern and for manufacturing optical component, circuit board and imprinting mold
JP2015127384A (en) Photocurable composition, and method for producing film, method for manufacturing optical component, method for manufacturing circuit board, method for manufacturing electronic component, and cured product using the photocurable composition
WO2016120944A1 (en) Adhesion layer-forming composition, method of manufacturing cured product pattern, method of manufacturing optical component, method of manufacturing circuit board, method of manufacturing imprinting mold, and device component
WO2016098314A1 (en) Adhesion layer composition, methods for forming adhesion layer and cured product pattern, and methods for manufacturing optical component, circuit board, imprinting mold and device component

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15869523

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20177018766

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 15869523

Country of ref document: EP

Kind code of ref document: A1