JP2011165831A - Pattern forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pattern forming method which can inhibit deterioration of a resin mold. <P>SOLUTION: In the pattern forming method, a liquid transfer receiving layer including photocurable components is sandwiched between a substrate and a mold with uneven patterns formed thereon and is shaped. After that, the transfer receiving material layer is exposed to light and is turned into a photocured layer. The mold is released from the photocured layer. The mold comprises an organic polymer compound. The number average molecular weight of all the components contained in the transfer receiving material layer is 350 or more and the components which have a molecular weight of less than 300 constitute less than 50 mass% of the total components of the transfer receiving material layer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pattern forming method using optical imprint lithography, and more particularly to a pattern forming method suitable for manufacturing a fine pattern such as a semiconductor integrated circuit and an optical element.

  With the increase in density and speed of semiconductor integrated circuits, the pattern line width of integrated circuits has been reduced, so that a technique capable of manufacturing a fine pattern is required. As a method for forming a fine pattern, optical nanoimprint lithography has attracted attention. Optical nanoimprint lithography is a process in which a transfer material is filled into a pattern of a mold by pressing a mold having a fine concavo-convex pattern against the transfer material such as a photocurable composition provided on a substrate, and then exposed. Then, the mold is released from the transfer material, thereby forming a pattern in which the concave / convex pattern of the mold is transferred to the transfer material (see Patent Document 1).

  Since the metal mold having a fine uneven pattern used in such optical nanoimprint lithography is expensive, the shape of the metal master having the fine uneven pattern is made of an organic material such as a cyclic olefin polymer or polydimethylsiloxane (PDMS). A method is known in which a resin mold is prepared by transferring it to a polymer compound (hereinafter referred to as resin), and this resin mold is used for optical nanoimprint (see Patent Document 2 and Non-Patent Document 1).

  However, such a resin mold has poor durability, and when used multiple times for pattern formation in optical nanoimprint lithography, there is a problem that the mold deteriorates and becomes cloudy or the mold releasability decreases. Such a problem is not limited to optical nanoimprint lithography, but also exists when the pattern size is larger than that of optical nanoimprint lithography.

US Pat. No. 6,334,960 WO2006 / 112062 pamphlet

Choi, Won Moook et al., “Microelectronic Engineering”, 70, No. 1, 2003, pp. 131-136.

  This invention makes it a subject to provide the pattern formation method which can suppress deterioration of resin molds in view of such a situation.

  As a result of various studies conducted by the present inventors to solve the above-described problems, the material layer to be transferred contains a photocurable component in a specific range in photoimprint lithography using a resin mold. Thus, the inventors have found that the above problems can be solved, and have reached the present invention.

  According to the first aspect of the present invention, after forming a liquid transfer material layer containing a photocurable component between a substrate and a mold having an uneven pattern, the transfer material layer is exposed to light. A pattern forming method of forming a photocured layer, and releasing the mold from the photocured layer, wherein the mold is made of an organic polymer compound, and the number average molecular weight of all components contained in the transferred material layer is 350 In the pattern forming method, the component having a molecular weight of less than 300 is less than 50% by mass among all the components in the transfer material layer.

  According to a second aspect of the present invention, there is provided the pattern forming method according to the first aspect, wherein the organic polymer compound is a polymer having a siloxane bond or a cyclic olefin polymer.

  ADVANTAGE OF THE INVENTION According to this invention, degradation of the resin mold in optical imprint lithography can be suppressed by making the photocurable component contained in a to-be-transferred material layer into a specific range. Therefore, the resin mold can be used repeatedly.

It is sectional drawing which shows the outline of the pattern formation method of this invention.

Hereinafter, the present invention will be described in detail with reference to FIG. 1 which is a cross-sectional view showing an example of the pattern forming method of the present invention.
In the pattern forming method of the present invention, a liquid transfer material layer 2 containing a photocurable component is sandwiched between a substrate 1 and a mold 3 on which an uneven pattern is formed, and then the transfer material layer 2 is exposed. The pattern forming method of forming the photocured layer 4 and releasing the mold 3 from the photocured layer 4, wherein the mold 3 is made of an organic polymer compound, and the number average of all components contained in the transfer material layer 2 In this pattern forming method, the molecular weight is 350 or more, and the components having a molecular weight of less than 300 out of all the components in the transferred material layer 2 are less than 50% by mass.

  Specifically, first, as shown in FIG. 1A, a photocurable composition containing a photocurable component is applied on the substrate 1 to contain the photocurable component on the substrate 1. A transfer material layer 2 is provided. The photocurable composition refers to a composition comprising a photocurable component and a solvent and an additive that are added as necessary. In addition, although the photocurable composition was apply | coated on the board | substrate 1 in Fig.1 (a), you may apply | coat a photocurable composition to the mold 3. FIG.

  The substrate 1 may be any substrate as long as the transfer material layer 2 can be provided. For example, the substrate 1 may be a substrate used in a pattern forming method by a normal optical imprint lithography. Specific examples include transparent inorganic substrates such as glass, quartz, and sapphire, transparent synthetic resin substrates such as polycarbonate, polyethylene terephthalate (PET), and triacetyl cellulose, semiconductor substrates such as silicon wafers, GaAs, InAs, and GaN. A compound semiconductor, a metal, a metal oxide, etc. are mentioned. In addition, at least one of the substrate 1 or the mold 4 needs to be transparent. The surface of the substrate 1 may be subjected to pretreatment in order to improve adhesion to the transfer material layer 2 or to improve the application state of the transfer material layer 2. Specific examples of the pretreatment include wet surface cleaning, surface modification by plasma and ozone cleaning, treatment with an adhesion improver such as a silane coupling agent, and the like.

  The mold 3 is made of a resin, that is, an organic polymer compound, and it is sufficient that a desired uneven pattern is formed on the surface. Organic polymer compounds may be proteins, nucleic acids, lipids, polysaccharides such as cellulose and starch, natural polymers such as natural rubber, and synthetic resins such as polyvinyl chloride, polyethylene, and phenol resin, nylon, vinylon, and polyester. , Polymers having a siloxane bond such as polyethylene terephthalate, synthetic rubber, polydimethylsiloxane (PDMS), cycloolefin polymers such as trade name ZEONOR (manufactured by ZEON Corporation), trade name ARTON (manufactured by JSR Corporation), etc. Or a cyclic olefin polymer such as a cycloolefin copolymer, or a photocured product of a photocurable composition.

  The mold 3 made of such an organic polymer compound has a problem that the durability is poor and the mold 3 deteriorates after being used multiple times in optical imprint lithography. However, in the pattern forming method of the present invention, the deterioration of the mold is suppressed. can do. The mold 3 may be a mold made of an organic polymer compound containing fluorine. However, in the case of the mold 3 containing fluorine, since the oil repellency of the mold material is increased, it becomes difficult to fill the uneven material pattern of the transfer material layer 2 into the uneven pattern of the mold 3. A mold 3 made of an organic polymer compound is preferable. In the pattern formation method of this invention, even if the mold 3 does not contain a fluorine, there exists an effect which can suppress deterioration of a mold.

  And the uneven | corrugated pattern currently formed in the mold 3 surface may be the same as the uneven | corrugated pattern currently formed in the surface of the mold 3 used in normal optical imprint lithography, However, it is limited to it It is not what is done. For example, it is good also as the mold 3 which formed the recessed part by forming a hollow in the surface of the mold material which consists of organic polymer compounds, and the part which protruded relatively to the surface side becomes a convex part in this case. Moreover, it is good also as the mold 3 which formed the convex part by providing a processus | protrusion on the surface of a mold material, and the part recessed relatively inside becomes a recessed part in this case. Of course, a master 3 having an uneven pattern formed by providing depressions or protrusions on the surface of metal or the like may be used, and the mold 3 made of an organic polymer compound formed using this master as a mold may be used. In addition, the shape of the cross section of each concave portion of the concave / convex pattern may be a square, a rectangle, a half moon shape, or a shape similar to those shapes, and each concave portion has, for example, a depth of about 1 nm to 100 μm and an opening width. May be about 1 nm to 100 μm.

  Further, in the present invention, since the deterioration of the mold 3 is suppressed and the durability is high, the mold 3 is releasable in the subsequent release step, but in order to further improve the releasability, The surface of 3 may be subjected to a mold release treatment. For the release treatment, a known release treatment agent exemplified by a perfluoro- or hydrocarbon-based polymer compound, an alkoxysilane compound or a trichlorosilane compound, diamond-like carbon, or the like is used by a gas phase method or a liquid phase method. Can be done. However, since the mold release process takes time, a mold 3 that is not subjected to the mold release process is preferable.

  The transfer material layer 2 is liquid around room temperature of 20 to 30 ° C. and does not substantially contain a solvent, and is formed of a photocurable composition containing a predetermined photocurable component. Since the mold 3 made of an organic polymer compound has lower mechanical strength than a mold made of an inorganic material such as a metal, the transferred material layer 2 can be smoothly and appropriately applied to the uneven pattern of the mold 3 without applying high pressure. The material to be transferred 2 needs to be in a liquid state so as to be filled. For example, the viscosity of the transfer material layer 2, specifically, the viscosity of the photocurable composition when the photocurable composition forming the transfer material layer 2 does not contain a solvent, and the photocurable composition When contains a solvent, the viscosity of the photocurable composition in a state excluding the solvent is 1000 Pa · s or less at 25 ° C. Examples of the viscosity measuring method include a method of measuring using a B-type viscometer manufactured by Tokyo Keiki Co., Ltd. Further, in order to avoid the deterioration of the mold 3, the transfer material layer 2 needs to contain substantially no solvent. For example, the content of the solvent is 10% by mass or less, preferably 5% by mass or less of the transfer material layer 2. The solvent is an organic solvent used when diluting a photocurable component or the like, and is a component that does not substantially remain in the photocured layer 4.

  The photocurable component contained in the transferred material layer 2 refers to a component that reacts and cures upon exposure. Specifically, if it is a photodimerization-type photocurable composition, it may be a photocrosslinkable photocurable composition such as a resin having a photodimer group such as a cinnamic acid ester resin or a cyclized rubber-bisazide. For example, a photopolymerizable photocurable composition such as a photocrosslinking agent and a polymer such as a cyclized rubber, an ene / thiol type, a radical, or a cation is a compound having a photopolymerizable group and a photopolymerization initiator. In addition, it is preferable that the photocurable component to contain is a photopolymerization type | mold from surfaces, such as versatility.

  The compound having a photopolymerizable group refers to a compound having a radical polymerizable group or a cationic polymerizable group. Examples of the radical polymerizable group include acryloyl group, methacryloyl group, vinyl group and allyl group. Examples of the cationic polymerizable group include an epoxy group, a vinyloxy group, and an oxetanyl group.

  Examples of the compound having a radical polymerizable group include isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (poly) propylene glycol mono (meta) ) Monofunctional radical polymerizable compounds such as (meth) acrylates such as acrylate and t-butyl (meth) acrylate, (meth) acrylamides such as morpholine (meth) acrylamide, N-vinylpyrrolidone, N-vinylcaprolactone and styrene Trimethylolpropane tri (meth) acrylate, alkylene oxide modified trimethylolpropane tri (meth) acrylate, alkylene glycol di (meth) acrylate, dialkylene glycol (meth) acrylate Trialkylene glycol (meth) acrylate, tetraalkylene glycol di (meth) acrylate, polyalkylene glycol (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate , Neopentyl glycol di (meth) acrylate, dicyclopentenyl di (meth) acrylate, diallyl phthalate, diallyl fumarate, alkylene oxide modified bisphenol A di (meth) acrylate, monofunctional or polyfunctional Epoxy (meth) acrylate, urethane (meth) acrylate, fluorine-containing (meth) acrylate, and the like.

  Representative examples of the compound having a cationic polymerizable group include cyclic ether compounds such as aromatic, alicyclic or aliphatic epoxy compounds, and oxetane compounds, vinyl ether compounds, and the like. Examples of the aromatic epoxy compound include di- or polyglycidyl ether of bisphenol A or its alkylene oxide adduct, di- or polyglycidyl ether of hydrogenated bisphenol A or its alkylene oxide adduct, and novolak-type epoxy resin. Examples of the alicyclic epoxy compound include a cyclohexene oxide-containing compound or a cyclopentene oxide-containing compound obtained by epoxidizing at least one cyclohexene ring or cyclopentene ring-containing compound with an oxidizing agent. Examples of the aliphatic epoxy compound include alkyl glycidyl ether, alkylene glycol diglycidyl ether, polyhydric alcohol polyglycidyl ether, polyalkylene glycol diglycidyl ether, and the like. Examples of oxetane compounds include bisphenol A type oxetane compounds, bisphenol oxetane compounds, bisphenol S type oxetane compounds, xylylene type oxetane compounds, phenol novolac type oxetane compounds, cresol novolac type oxetane compounds, alkylphenol novolak type oxetane compounds, biphenol type oxetane compounds, Examples thereof include xylenol type oxetane compounds, naphthalene type oxetane compounds, dicyclopentadiene type oxetane compounds, oxetaneated products of condensates of phenols and aromatic aldehydes having a phenolic hydroxyl group. Examples of vinyl ether compounds include ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, and trimethylol. Di- or trivinyl ether compounds such as propane trivinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexanedimethanol monovinyl ether, n-pro Vinyl ether, isopropyl vinyl ether, dodecyl vinyl ether, diethylene glycol monovinyl ether, and octadecyl vinyl ether.

  The compounds having a photopolymerizable group may be used alone or in combination of two or more, and a compound having a radical polymerizable group and a compound having a cationic polymerizable group may be used in combination.

  The photopolymerization initiator refers to a compound that generates an active species such as a radical or a cation capable of initiating polymerization of the compound having the photopolymerizable group upon irradiation with light. Photopolymerization initiators can be classified into radical polymerization initiators and cationic polymerization initiators. Examples of radical polymerization initiators include benzophenone, benzyldimethyl ketal, α-hydroxyalkylphenones, α-aminoalkylphenones, acylphosphine oxides, titanocenes and oxime esters, trihalomethyltriazines, and other trihalomethyls. And a compound having a group. Examples of the cationic polymerization initiator include aromatic sulfonium salts and aromatic iodonium salts. The polymerization initiators may be used alone or in combination of two or more, and a radical polymerization initiator and a cationic polymerization initiator may be used in combination. Furthermore, you may use a sensitizer with a photoinitiator.

  As for content of the compound which has a photopolymerizable group in a photocurable composition, 50-99.99 mass parts is preferable with respect to 100 mass parts of total amounts of a photocurable composition. When the amount is less than 50 parts by mass, the amount of the photopolymerizable group is small. When the amount exceeds 99.99 parts by mass, the ratio of the photopolymerization initiator to the compound having the photopolymerizable group is decreased. This is because of a decrease. Further, the compound having a photopolymerizable group having two or more photopolymerizable groups in one molecule is contained in an amount of 5 parts by mass or more, preferably 20 parts by mass or more with respect to 100 parts by mass of the total amount of the photocurable composition. Is desirable. This is to improve the mechanical strength of the photocured product by photocrosslinking. Moreover, as for content of the photoinitiator in a photocurable composition, 0.01-20 mass parts is preferable with respect to 100 mass parts of compounds which have a photopolymerizable group. If it is less than 0.01 mass part, the ratio of the photoinitiator with respect to the compound which has a photopolymerizable group will become low, and photocurability will fall. Moreover, when it exceeds 20 mass parts, it is because the solubility of the photoinitiator with respect to a photocurable composition falls and it is not practical.

  And it is desirable that the transfer material layer 2 formed using such a photocurable composition does not substantially contain a solvent. Therefore, the photocurable composition does not contain a solvent, or even if it contains a solvent, the transfer material layer 2 can be prevented from containing a solvent by removing the solvent by heating or the like. Things are good. The transfer material layer 2 needs to be in a liquid state with the solvent removed.

  In the present invention, the number average molecular weight of all components contained in the transfer material layer 2 is 350 or more. Within the above range, as shown in the examples described later, since the impregnation of the component 3 contained in the transfer material layer 2 into the mold 3 is small, deterioration of the mold 3 can be suppressed. The number average molecular weight Mn of all components contained in the transfer material layer 2 is represented by the following formula (1).

  Here, if Ni = Wi / Mi (Wi; weight fraction of component i), the number average molecular weight Mn can be expressed by the following formula (2).

  In the case of a single component having no molecular weight distribution, the molecular weight of each component contained in the transfer material layer 2 is obtained by calculation from the composition formula. On the other hand, in the case of a component having a molecular weight distribution such as an oligomer or a polymer, it can be determined using a known molecular weight measurement method such as an osmotic pressure method, a light scattering method, a mass spectrometry method, or a gel filtration chromatography (GPC) method. .

  Further, it is preferable for the transfer material layer 2 that the ratio of the low molecular weight component is low because the impregnation into the mold 3 is small. In the present invention, the component having a molecular weight of less than 300 among the components contained in the transfer material layer 2 is less than 50% by mass, preferably 40% by mass or less. Moreover, it is more preferable that the component having a molecular weight of less than 250 is 30% by mass or less.

  Here, in the photoimprint lithography, in order to satisfactorily fill the concave / convex pattern of the mold, a photocurable composition having a low viscosity, that is, a photocurable composition containing a large amount of low molecular weight components is usually used. Although a transfer material layer is formed, when such a photocurable composition is used, when it contacts with a mold made of a cyclic olefin polymer as in Patent Document 2, for example, the mold deteriorates and the releasability decreases. Moreover, when a polydimethylsiloxane mold as in Non-Patent Document 1 is used, the mold is deteriorated and white turbid because the photocurable component is impregnated into the polydimethylsiloxane. In order to suppress such deterioration of the mold, it is necessary to coat the mold surface with a fluorine-containing material, to form a mold containing fluorine, or to increase the fluorine content of the transfer material layer.

  However, in the present invention, by using a specific material layer to be transferred as described above in contact with the mold, the surface of the mold can be surface-treated with a fluorine-containing material or the like, or a mold containing fluorine can be used. Moreover, deterioration of resin molds, such as a cyclic olefin polymer and a polymer which has a siloxane bond, can be suppressed.

  In addition, the photocurable composition may contain the additive as needed. However, in order to prevent impregnation of the mold 3 and suppress deterioration of the mold 3, it is desirable that the molecular weight of the additive is, for example, 300 or more. Additives include non-photo-curable oligomers and non-photo-curable polymers, adhesion-imparting agents (for example, silane coupling agents), organic solvents, leveling agents, plasticizers, fillers, antifoaming agents, flame retardants, Stabilizers, antioxidants, fragrances, thermal crosslinking agents, colorants, polymerization inhibitors and the like can be mentioned. In order to further improve the mold releasability, an ionic liquid may be added. Examples of the ionic liquid include those having a melting point of 40 ° C. or lower. Among various ionic liquids, an ionic liquid having a photopolymerizable group is preferable because it is a photocurable component and does not cause problems such as oozing out on the surface of a photocured product after exposure. And in this invention, you may add fluorine-containing compounds, such as a photocurable component and an additive component, to a photocurable composition. However, since the fluorine-containing compound generally has low solubility in components not containing fluorine, it is preferable that the addition amount is small. The addition amount of a fluorine-containing compound is 10 mass% or less with respect to the photocurable composition except a solvent, for example, Preferably it is 5 mass% or less. In the pattern forming method of the present invention, impregnation into the mold 3 can be suppressed without adding a fluorine-containing compound to the photocurable composition.

  A method for forming the transfer material layer 2 on the substrate 1 or the mold 3 using the photocurable composition is not particularly limited. For example, application or dropping of the photocurable composition, specifically, spin coating, Examples thereof include roll coating, dip coating, gravure coating, die coating, curtain coating, inkjet coating, and dispenser coating.

  The thickness of the transfer material layer 2 may be set in consideration of the amount of the transfer material layer 2 filled in the recesses of the uneven pattern formed on the mold 3, for example, the depth of the recesses of the uneven pattern. Good. Further, the transfer material layer 2 may be provided so as to cover the entire surface of the mold 3 and the substrate 1, or may be provided so as to cover only a part thereof.

  In addition, when the photocurable composition which forms the to-be-transferred material layer 2 contains a solvent, after applying the photocurable composition to the board | substrate 1 and forming the layer which consists of a photocurable composition, it heats. Thus, the solvent is removed to form the transfer material layer 2.

  Next, as shown in FIG. 1 (b), the transfer material layer 2 is sandwiched between the substrate 1 and the mold 3 to form (molding step). Here, the substrate 1 may be pressed against the mold 3, the mold 3 may be pressed against the substrate 1, or both the substrate 1 and the mold 3 may be pressed. The force which presses the board | substrate 1 or the mold 3 can be about 0.01-100 Mpa, for example. Further, pressing by the weight of the mold 3 or the substrate 1 may be performed without applying force. In this way, by pressing the mold 3 against the substrate 1, the uneven material pattern of the mold 3 is filled with the transfer material layer 2 to be molded. Although it is preferable to keep the transfer material layer 2 and the mold 3 both horizontal and contact the transfer material layer 2 and the mold 3, it is necessary to limit the transfer material layer 2 and the mold 3 to keep horizontal if there is no problem with the pattern to be obtained. There is no. In the molding process, a conventional apparatus for optical imprint lithography can be used.

Next, as shown in FIG. 1C, the transferred material layer 2 is exposed and cured in a state in which the uneven material pattern of the mold 3 is filled with the transferred material layer 2 and formed into a photocured layer 4 ( Photocuring step). The light source used for exposure may be any light source that can irradiate light having a wavelength at which the transfer material layer 2 is cured. Examples of light sources include low pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, metal halide lamps, xenon lamps, carbon arc, mercury xenon lamps, excimer lasers such as XeCl, KrF and ArF, ultraviolet or visible light lasers, and ultraviolet light. Or visible light LED etc. are mentioned. The light irradiation amount may be an amount that can cure the transfer material layer 2. When the present invention is industrially carried out, it is usually preferable to select an irradiation dose within a range of 10 J / cm ² or less. In addition, light is irradiated to the to-be-transferred material layer 2 from the side of the member which is substantially transparent with respect to the light irradiated among the substrate 1 and the mold 3.

  Thereafter, as shown in FIG. 1 (d), the mold 3 is released from the photocured layer 4 to form a pattern of the photocured layer 4 to which the concave / convex pattern of the mold 3 is transferred on the substrate 1. (Release process). When the mold 3 is deteriorated, the photocuring layer 4 adheres to the mold 3 at the time of releasing, and the photocuring layer 4 having an uneven pattern obtained by accurately transferring the uneven pattern of the mold 3 is formed. However, in the present invention, since the deterioration of the mold 3 is suppressed, even if the pattern formation by optical nanoimprint lithography is performed a plurality of times using the same mold 3, the unevenness obtained by accurately transferring the unevenness pattern of the mold 3 A photocured layer 4 having the following pattern can be formed. Note that, when releasing, it is preferable to release the substrate 1 and the mold 3 while keeping them both horizontal, but it is not necessary to limit to keeping them horizontal.

  In addition, when a photocurable composition contains the component hardened | cured with a heat | fever, in order to improve the intensity | strength of a molding, it further has the process of hardening the photocuring layer 4 with a heat | fever after a mold release process. May be.

  Hereinafter, the present invention will be described more specifically with reference to examples. In addition, this invention is not limited to a following example.

Example 1
<Preparation of photocurable composition>
As a photopolymerizable compound, 20 parts by mass of dicyclopentanyl acrylate (molecular weight 206), 10 parts by mass of trimethylolpropane triacrylate (molecular weight 296), bifunctional urethane acrylate (product name: Art Resin UN-7600, Negami Industrial Co., Ltd.) 65 parts by mass) and 5 parts by mass of 2-hydroxy-2-methyl-1-phenylpropan-1-one (molecular weight 164) as a photopolymerization initiator are stirred and mixed at room temperature to form a liquid containing no fluorine. A photocurable composition A was prepared. The composition and the like are shown in Table 1. The molecular weight of Art Resin UN-7600 was determined from the molecular weight in terms of polystyrene by GPC measurement (solvent: tetrahydrofuran (THF)). Art Resin UN-7600 had a number average molecular weight (Mn) of 2,824 and a weight average molecular weight (Mw) of 11,000.

<Durability evaluation of polydimethylsiloxane>
Evaluation was performed using a two-pack type polydimethylsiloxane (product name: Silpot 184, manufactured by Dow Corning) as a polymer having a siloxane bond. Specifically, first, the main component of Silpot 184 and the catalyst component were mixed at a weight ratio of 10: 1 and then thermally cured at 150 ° C. for 1 hour to form plate-like polydimethylsiloxane (PDMS). The photocurable composition A is dropped on the plate-like PDMS, and the photocurable composition A, which is the transfer material layer, is sandwiched between the polyethylene terephthalate (PET) film, which is the substrate, and the PDMS. The photocurable composition A was cured by exposure to ultraviolet rays at 1 J / cm ² using a high pressure mercury lamp, and then the photocured product of the photocurable composition A and the PET film were peeled from PDMS. This series of operations (photocuring test) consisting of dripping, exposure and peeling was repeated, and the surface roughness of PDMS was observed with an optical microscope. A: No surface roughness after 25 photocuring tests, ○: Light Surface roughness occurred after curing test 16-24 times, Δ; surface roughness occurred when photocuring test 6-15 times, x: surface roughness occurred within 5 photocuring tests. The results are shown in Table 1. As shown in Table 1, when the photocurable composition A was photocured 25 times on PDMS, the surface of PDMS did not show roughness such as white turbidity or cracks, and the release property was not deteriorated. showed that. Therefore, when the photocurable composition A is used as a transfer material when forming a pattern by photoimprint lithography, a polymer having a siloxane bond even if a mold that does not contain fluorine and is not surface-treated is used. It was confirmed that the manufactured mold did not deteriorate.

<Durability evaluation of cyclic olefin polymer>
Evaluation was performed using a ZEONOR film (product name: ZF14-060, manufactured by Nippon Zeon Co., Ltd.) as a cyclic olefin polymer. Specifically, the photocurable composition A is dropped on the ZEONOR film, and the photocurable composition A that is the transfer material layer is sandwiched between the polyethylene terephthalate (PET) film that is the substrate and the ZEONOR film, and PET After the photocurable composition A was cured by exposing the film surface to ultraviolet rays at 1 J / cm ² using an ultra-high pressure mercury lamp, the photocured product of the photocurable composition A and the PET film were peeled from the ZEONOR film. . Repeated a series of operations (photocuring test) consisting of dripping, exposing and peeling, ◎: No surface roughness after 10 times of photocuring test, ○: Releasability decreased after 4-9 times of photocuring test, Δ: Photocuring The test was evaluated as a decrease in releasability after 2 to 3 tests, x: a decrease in releasability after 1 photocuring test. The results are shown in Table 1. As shown in Table 1, the photocurable composition A exhibited good durability with no decrease in releasability even when photocured 10 times on a ZEONOR film. Therefore, it was confirmed that the cyclic olefin polymer mold does not deteriorate when the photocurable composition A is used as a transfer material when forming a pattern by photoimprint lithography.

(Example 2)
A photocurable composition B was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and the cyclic olefin polymer with respect to the photocurable composition B was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, siloxane exhibits good durability with respect to any organic polymer compound, and when the photocurable composition B is used as a transfer material when forming a pattern by photoimprint lithography. It was confirmed that a mold made of an organic polymer compound such as a polymer having a bond or a cyclic olefin polymer does not deteriorate.

(Example 3)
A photocurable composition C was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition C was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, the durability was exhibited with respect to any organic polymer compound, but the durability was slightly lowered as compared with Examples 1 and 2.

Example 4
A photocurable composition D was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition D was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, siloxane exhibits good durability against any organic polymer compound, and when a photocurable composition D is used as a transfer material when forming a pattern by photoimprint lithography, It was confirmed that a mold made of an organic polymer compound such as a polymer having a bond or a cyclic olefin polymer does not deteriorate.

(Example 5)
A photocurable composition E was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition E was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, siloxane exhibits good durability with respect to any organic polymer compound, and when a photocurable composition E is used as a transfer material when forming a pattern by photoimprint lithography. It was confirmed that a mold made of an organic polymer compound such as a polymer having a bond or a cyclic olefin polymer does not deteriorate.

(Example 6)
A photocurable composition F was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition F was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, siloxane exhibits good durability against any organic polymer compound, and when a photocurable composition F is used as a transfer material when forming a pattern by photoimprint lithography. It was confirmed that a mold made of an organic polymer compound such as a polymer having a bond or a cyclic olefin polymer does not deteriorate.

(Example 7)
A photocurable composition G was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition G was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, siloxane exhibits good durability with respect to any organic polymer compound, and when the photocurable composition G is used as a transfer material when forming a pattern by photoimprint lithography, It was confirmed that a mold made of an organic polymer compound such as a polymer having a bond or a cyclic olefin polymer does not deteriorate.

(Comparative Example 1)
A photocurable composition H was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition H was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, as a result of carrying out photocuring of the photocurable composition H on PDMS, the surface roughness of PDMS generate | occur | produced between the photocuring tests 6-15 times. Moreover, in durability evaluation in a ZEONOR film, mold release property fell by one photocuring test, and durability was not acquired.

(Comparative Example 2)
A photocurable composition I was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition I was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, as a result of carrying out photocuring of the photocurable composition I on PDMS, surface roughness of PDMS occurred between 6 to 15 photocuring tests. Moreover, in durability evaluation in a ZEONOR film, mold release property fell by one photocuring test, and durability was not acquired.

(Comparative Example 3)
A photocurable composition J was prepared in the same manner as in Example 1 except that the composition shown in Table 1 was used. Further, the durability of PDMS and cyclic olefin polymer with respect to the photocurable composition J was evaluated in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, as a result of photocuring the photocurable composition J on PDMS, surface roughness of the PDMS occurred within 5 photocuring tests. Moreover, in durability evaluation in a ZEONOR film, mold release property fell by one photocuring test, and durability was not acquired.

DESCRIPTION OF SYMBOLS 1 Substrate 2 Transfer material layer 3 Mold 4 Photocuring layer

Claims (2)

A liquid transfer material layer containing a photocurable component is sandwiched and molded between a substrate and a mold having a concavo-convex pattern, and then the transfer material layer is exposed to form a photocuring layer. A pattern forming method for releasing the mold,
The mold is made of an organic polymer compound,
The number average molecular weight of all components contained in the transfer material layer is 350 or more, and among all the components in the transfer material layer, a component having a molecular weight of less than 300 is less than 50% by mass. A pattern forming method.   The pattern forming method according to claim 1, wherein the organic polymer compound is a polymer having a siloxane bond or a cyclic olefin polymer.

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