JP5887871B2 - Film forming material and pattern forming method - Google Patents

Description

  The present invention relates to a film forming material and a pattern forming method using the film forming material.

  In recent years, the imprint method has attracted attention as a fine processing technique that is inexpensive and has high mass productivity. The imprint method forms a pattern on a film-forming material (resist material, etc.) formed on a substrate in the manner of a stamp. Unlike exposure techniques that use conventional optical exposure equipment, the pattern resolution is exposed. Independent of wavelength. Therefore, application to a wide range of fields is expected as a fine processing technology such as patterned media, photonic crystal, LSI (Large Scale Integration), and MEMS (Micro Electro Mechanical System).

  In the imprint method, for example, a thermoplastic film-forming material is used, and the film-forming material on the substrate is softened by heating, and a mold (mold) in which a predetermined uneven pattern is finely processed is pressed in advance, and the recess is pressed. A thermal imprint method for filling a film forming material is known. In addition, a thermal imprint method is also known in which a thermosetting film forming material is used, a mold is pressed against a soft film forming material on a substrate, and the film forming material filled in the recess is cured by heating. . Also known is a photoimprinting method in which a photocurable film-forming material is used, a mold is pressed against a soft film-forming material on a substrate, and the film-forming material filled in the concave portion is cured by light irradiation. .

JP 2009-223998 A

Applied Physics Letters, 1995, Vol. 67, No. 21, pp. 3114-3116 Semiconductor FPD World, August 2007, pp. 48-51

  As described above, in the imprint method, a mold is pressed against a film forming material on a substrate, and a film on which a reverse pattern of the concave / convex pattern of the mold is transferred is formed on the substrate. After the transfer, the mold is separated from the coating (mold release).

  However, at the time of mold release, a part of the film may adhere to the mold and peel off. When the film peels off due to adhesion to the mold, the resolution of the pattern formed on the film is impaired. In addition, depending on the mold material and film forming material used, it may not be easy to remove the film attached to the mold, and depending on the method of removal, the uneven pattern on the mold side may be lost. . If the film remains attached to the mold or the uneven pattern of the mold is missing, it becomes difficult to perform high-resolution patterning at the next imprint using the mold.

According to one aspect of the present invention, it includes a component containing a compound having a carbon-carbon unsaturated bond, and a polymerization initiator for initiating a polymerization reaction of the compound, and as the compound, a carbon-carbon unsaturated bond, There is provided a film forming material comprising a silicon compound having a predetermined chemical structure having a silicon atom to which an alkoxy group is not bonded.

According to another aspect of the present invention, a film forming material is formed on a substrate, and a mold having a concavo-convex pattern is pressed against the formed film forming material to form an inverted pattern of the concavo-convex pattern. A step of forming a film having the reversal pattern using the film forming material on which the reversal pattern is formed, and a step of separating the mold from the formed film. The film forming material includes a component containing a compound having a carbon-carbon unsaturated bond, and a polymerization initiator for initiating a polymerization reaction of the compound, and the compound includes a carbon-carbon unsaturated bond, an alkoxy group There is provided a pattern forming method comprising a silicon compound having a predetermined chemical structure having a silicon atom to which is not bonded.

  According to the disclosed technology, it becomes possible to suppress adhesion of a film to a mold at the time of mold release, thereby reducing the resolution of a pattern formed on a substrate and generating a pattern defect formed on the mold. Therefore, high-resolution patterning can be performed.

It is explanatory drawing (the 1) of the imprint method. It is explanatory drawing (the 2) of the imprint method. It is explanatory drawing of surface treatment.

1 and 2 are explanatory diagrams of the imprint method.
In the imprint method, first, a film forming material 2 is provided on a substrate 1 set on a predetermined stage 10 by a method such as coating (FIGS. 1 and 2A). Then, a mold 3 provided with a predetermined concavo-convex pattern 3 a is pressed against the film forming material 2 on the substrate 1 in a state where the film forming material 2 is soft, and the concavo-convex pattern 3 a of the mold 3 is pressed against the film forming material 2. The reverse pattern 3b is transferred (FIGS. 1 and 2B). Thereafter, the film forming material 2 is cured using heat or light energy (for convenience, shown by an arrow in FIG. 2C), thereby forming the film 2a on which the reverse pattern 3b of the uneven pattern 3a of the mold 3 is formed. Is formed on the substrate 1 (FIGS. 1 and 2C). After the formation of the coating 2a, the mold 3 is separated from the coating 2a on the substrate 1 (release) (FIGS. 1 and 2D).

In addition, the uneven | corrugated pattern 3a and the inversion pattern 3b shown here are only examples, and are not limited to the form shown in figure.
The film 2a formed on the substrate 1 is used as a permanent film to which the reversal pattern 3b of the mold 3 is transferred, or used as a mask when performing processing such as etching on the substrate 1. Can do.

  The mold 3 used for the imprint method can be provided with a fine uneven pattern 3a of the order of nanometers, for example. In the imprint method, such a concavo-convex pattern 3a of the mold 3 can be transferred to the film forming material 2 (film 2a).

  Various materials can be used for the film forming material 2 according to the application (permanent film, mask, etc.) of the film 2a to be formed. As the film forming material 2, a thermoplastic, thermosetting, photocurable material or the like can be used.

  For example, if the film forming material 2 is thermoplastic, the film forming material 2 provided on the substrate 1 is softened by heating, the mold 3 is pressed thereon, and the recess is filled with the film forming material 2. Allow to cool and cure. If the film forming material 2 is thermosetting, the mold 3 is pressed against the soft film forming material 2 provided on the substrate 1, and the film forming material 2 filled in the recesses is cured by heating. These methods are called thermal imprint methods.

  Further, if the film forming material 2 is photocurable, the mold 3 is pressed against the soft film forming material 2 provided on the substrate 1, and the film forming material 2 filled in the concave portion is irradiated with light such as ultraviolet rays. It is cured by irradiation. This method is called an optical imprint method.

  Among the imprint methods as described above, the thermal imprint method is relatively versatile because the film forming material 2 has a wide range of choices and can be collectively transferred to a large area. However, in the thermal imprint method, since the film forming material 2 is heated and cooled, the throughput may be relatively low. In addition, the pattern accuracy may be relatively low due to the shrinkage of the film forming material 2 due to a temperature change.

  On the other hand, in the optical imprint method, since the pattern is formed by light irradiation after the mold 3 is pressed against the film forming material 2, the throughput is relatively high, and the shrinkage of the film forming material 2 is suppressed. High pattern accuracy can be ensured. However, in the optical imprint method, for example, the film forming material 2 pressed against the mold 3 is irradiated with light through the mold 3 to cure the film forming material 2. In that case, the mold 3 needs to be made of a material that transmits light. From such a light-transmitting viewpoint, quartz can be used for the mold 3, but since quartz has a relatively low heat dissipation, it is not always easy to form the fine uneven pattern 3a by etching or the like. The production cost of the mold 3 may be relatively high.

  In the imprint method, after the mold 3 is pressed against the film forming material 2 to form the film 2a to which the uneven pattern 3a is transferred, a part of the formed film 2a adheres to the mold 3 at the time of release. There is a case. When the coating 2a is peeled off due to such adhesion to the mold 3, the resolution of the pattern formed on the coating 2a is impaired. Furthermore, it may be difficult to remove the coating 2 a attached to the mold 3. This is because the film 2a attached to the mold 3 is obtained by curing the film forming material 2, and is difficult to dissolve in a solvent or the like. If the film 2a attached to the mold 3 is forcibly removed, the concavo-convex pattern 3a of the mold 3 may be lost. If the film 2a remains attached to the mold 3 or the concave / convex pattern 3a of the mold 3 is missing, it becomes difficult to perform high-resolution patterning at the next imprinting using the mold 3.

Several countermeasures have been proposed for the adhesion of the coating 2 a to the mold 3.
First, as a first method, there is a method of improving adhesion between the substrate 1 and the film 2a (or film forming material 2) and suppressing adhesion of the film 2a to the mold 3. Also in the general semiconductor device manufacturing field, in order to improve the substrate adhesion of the coating, the substrate surface treatment with a silane coupling agent such as hexamethyldisilazane (HMDS) may be performed. This technique is also used in the imprint method, and the surface of the substrate 1 on which the coating 2a is formed is subjected to a surface treatment with the same silane coupling agent.

  Further, as a second method, there is a method of improving the mold releasability of the mold 3 from the coating 2 a and suppressing the adhesion of the coating 2 a to the mold 3. In this method, the surface of the mold 3 on the concave / convex pattern 3a side is previously subjected to a surface treatment with a silane coupling agent, a silane-based gas, or the like to suppress adhesion of the coating 2a to the mold 3.

  In the first method and the second method, adhesion of the coating film 2a to the mold 3 can be reduced as compared with the case where these methods are not used. However, these methods may not sufficiently suppress the adhesion of the coating 2a to the mold 3. Furthermore, these methods increase the number of surface treatment steps for the substrate 1 and the mold 3. In the case where the surface treatment is performed on the mold 3, the effect of the surface treatment may be reduced as the number of times the mold 3 is used increases.

  As a third method, a method of creating a replica mold called a replica mold has been proposed. This is because a replica mold is made from an expensive quartz mold (true mold) with a resin material, imprinted using the replica mold, and the use of the true mold is reduced. It is a method of suppressing the above. However, in this third method, although the use frequency of the true mold can be reduced, the procedure for producing the replica mold from the true mold is the same as the normal imprint method. Don't be.

  Therefore, here, as the film forming material 2, for example, a material containing the following components is used. That is, the film forming material 2 includes a component containing a compound having a carbon-carbon unsaturated bond in the molecule and a polymerization initiator for initiating a polymerization reaction of the compound. Here, the film forming material 2 contains a silicon compound having a silicon atom in addition to the carbon-carbon unsaturated bond as a compound having a carbon-carbon unsaturated bond in the component.

  In such a film-forming material 2, the polymerization initiator initiates a polymerization reaction of a compound (monomer) having a carbon-carbon unsaturated bond in the component by irradiation with light such as ultraviolet rays. When the polymerization reaction starts, the compounds in the components are polymerized one after another mainly at the carbon-carbon unsaturated bond part, and become high molecular weight. When this film-forming material 2 is used in an imprint method, the mold 3 is pressed against the soft film-forming material 2 and cured by polymerizing the compound in the component and increasing the molecular weight by, for example, light irradiation. A coated film 2a (polymer) is obtained. Thereby, the film 2a to which the uneven pattern 3a of the mold 3 is transferred is formed.

  As described above, the film forming material 2 contains a silicon compound as a compound having a carbon-carbon unsaturated bond in its components. By including such a silicon compound in the component of the film forming material 2, the silicon compound is included in the polymer (the film 2a) to be formed. By including the silicon compound in the coating 2a, the adhesion of the coating 2a to the mold 3 is suppressed compared to the case where the silicon compound is not included when releasing the concavo-convex pattern 3a after the transfer.

  As the silicon compound included in the film forming material 2, for example, a silicon compound having a silicon atom to which an alkoxy group is not bonded is used. When a silicon compound having a silicon atom to which an alkoxy group is bonded is used, in addition to the carbon-carbon unsaturated bond portion, the alkoxy group portion also serves as a reaction point for polymerization, making the reaction control difficult, This may cause a decrease in storage stability. From such a viewpoint, a silicon compound having a silicon atom to which no alkoxy group is bonded is used for the film forming material 2. Details of this point will be described later.

  The polymerization initiator for the film forming material 2 may be one that initiates a polymerization reaction by irradiation with light such as ultraviolet rays as described above, or one that initiates a polymerization reaction by irradiation with an electron beam. In addition to such an energy beam such as light and electron beam, it is also possible to use one that initiates the polymerization reaction by heat.

  Thus, by using the film forming material 2 containing a predetermined silicon compound, it becomes possible to form the film 2a containing the silicon compound, thereby improving the mold releasability of the mold 3 from the film 2a. The adhesion of the coating 2a is suppressed. That is, the film forming material 2 itself and the film 2a itself contain a component that enhances the mold releasability. Therefore, for example, it is possible to omit a step of performing a surface treatment for bringing the coating 2a into close contact with the substrate 1 or performing a surface treatment for suppressing the adhesion of the coating 2a to the mold 3. Moreover, even if the number of times of use of the mold 3 increases, it is possible to stably maintain a high mold 3 releasability. Moreover, it is not necessary to prepare a member like the above replica mold.

  Since the adhesion of the film 2a to the mold 3 can be suppressed, it is possible to repeatedly perform high-resolution patterning using the mold 3, and may occur when the adhered film 2a is removed. It is also possible to suppress the loss of the uneven pattern 3a of the mold 3. By using the film forming material 2 containing the predetermined silicon compound as described above, it is possible to suppress the deterioration of the resolution of the pattern formed on the substrate 1 and the generation of defects in the uneven pattern 3a formed on the mold 3. High-resolution patterning can be performed.

  In addition, while using the film forming material 2 as described above, performing a surface treatment for bringing the film 2 into close contact with the substrate 1 or performing a surface treatment for suppressing the adhesion of the film 2 with the mold 3. Also good.

FIG. 3 is an explanatory diagram of the surface treatment. 3A is a diagram for explaining the surface treatment of the substrate, and FIG. 3B is a diagram for explaining the surface treatment of the mold.
For example, in order to improve the adhesion between the film 2 formed from the film forming material 2 and the substrate 1, before the film forming material 2 is formed, the HMDS is applied to the surface of the substrate 1 as shown in FIG. A process for forming the surface treatment layer 1c is performed in advance. Further, in order to improve the mold releasability of the mold 3 from the film 2a, trimethylsilyldimethylamide is applied to the surface of the mold 3 on the side of the concave / convex pattern 3a before being pressed against the film forming material 2 as shown in FIG. A process for forming the surface treatment layer 3c is performed using (TMSDMA) or the like.

  Either one or both of the surface treatment for the substrate 1 and the surface treatment for the mold 3 may be performed. If such a surface treatment is performed on the substrate 1 and the mold 3 in advance, peeling of the coating 2a from the substrate 1 (pattern peeling, pattern loss) and adhesion of the coating 2a to the mold 3 (mold adhesion) It becomes possible to suppress more effectively.

Hereinafter, the film forming material having the above-described configuration and the pattern forming method using the imprint method using such a film forming material will be described in more detail.
First, an example of the film forming material will be described.

  The film-forming material contains, as a first component, a silicon compound having a carbon-carbon unsaturated bond and a silicon atom to which no alkoxy group is bonded. As such a silicon compound, for example, a silicon compound represented by the following formula (1) can be used.

In the formula (1), s is an integer of 0 to 5, and at least one of Q _{1 to} Q ₃ has a chemical structure represented by the following formula (2).

Among Q _{1 to} Q ₃ , those not having the chemical structure represented by the formula (2) are alkyl groups having 1 to 5 carbon atoms.
Moreover, as a silicon compound contained as a 1st component, the silicon compound represented by following formula (3) can also be used, for example.

  In the formula (3), n is an integer of 0 to 5, and R1 to R3 have a chemical structure represented by at least one of the formula (4).

Among R1 to R3, those not having the chemical structure represented by the formula (4) are alkyl groups having 1 to 5 carbon atoms.
The silicon compounds represented by the above formulas (1) and (2) or the silicon compounds represented by the above formulas (3) and (4) are used alone as the first component of the film forming material. Alternatively, a plurality of types may be used in combination. The molecular weight of the silicon compound contained as the first component in the film-forming material is preferably in the range of 100 to 30000, more preferably in the range of 100 to 10000 in terms of polystyrene. If the molecular weight of the silicon compound is less than 100, sufficient film properties (such as mechanical strength) may not be obtained after curing, and if the molecular weight is greater than 30000, the viscosity increases and the coatability decreases. This is because there is a possibility.

  In addition, the film-forming material, as a second component, initiates the polymerization of the compound (including the silicon compound as described above) contained in the film-forming material, thereby polymerizing the compound in the film-forming material, increasing the molecular weight, etc. It contains a polymerization initiator that gives changes. The type of the polymerization initiator is not limited as long as it exhibits a polymerization initiating action, and various types can be used. For example, a polymerization initiator that starts polymerization by irradiation with light such as visible light, far ultraviolet light, near ultraviolet light, or deep ultraviolet light, or a polymerization initiator that starts polymerization by irradiation with an electron beam can be used. The polymerization initiator may be either a cationic polymerization initiator or a radical polymerization initiator.

  Examples of the cationic polymerization initiator include bis (4-tert-butyl) iodonium hexafluorophosphate, bis (4-tert-butyl) iodonium trifluoromethanesulfonate, 2- (3,4-dimethoxystyryl) -4, 6-bis (trichloromethyl) -1,3,5-triazine, diphenyliodonium hexafluoroarsenate, diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoromethanesulfonate, 2- [2- (furan-2-yl) vinyl]- 4,6-bis (trichloromethyl) -1,3,5-triazine, 4-isopropyl-4′-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate, 2- (4-methoxyphenyl) -4,6-bis ( Lichloromethyl) -1,3,5-triazine, 2- [2- (5-methylfuran-2-yl) vinyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, triphenylsulfonium Examples thereof include tetrafluoroborate, tri-p-tolylsulfonium hexafluorophosphate, tri-p-tolylsulfonium trifluoromethanesulfonate, and the like.

  Examples of the radical polymerization agent include acetophenone, p-anisyl, benzyl, benzoin, benzoin ethyl ether, benzoin isobutyl ether, benzoin isopropyl ether, benzoin methyl ether, benzophenone, 2-benzoylbenzoic acid, 4-benzoylbenzoic acid, 4, 4′-bis (diethylamino) benzophenone, 4,4′-bis (dimethylamino) benzophenone, 4,4′-dichlorobenzophenone, 2,2-diethoxyacetophenone, 2,4-ethylthiocisatin-9-one, 2,2-dimethoxy-2-phenylacetophenone, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 2-ethylanthraquinone, 1-hydroxychlorophenyl phenyl ketone, 2-hydroxy-2 -Methylpropiophenone, 2-isonitrosopropiophenone, methyl 2-benzoylbenzoate, 2-methyl-4 '-(methylthio) -2-morpholinopropiophenone, 2-phenyl-2- (p-toluenesulfonyl) And oxy) acetophenone.

  The cationic polymerization initiator and radical polymerization initiator are not limited to those described above, and other commercially available ones can be used as appropriate. Further, a plurality of types of cationic polymerization initiators can be used in combination, or a plurality of types of radical polymerization initiators can be used in combination.

  In addition, when using the film formed from a film formation material as a permanent film, the radical polymerization initiator which does not contain chlorine is suitable as a polymerization initiator. This is to prevent future corrosion caused by chlorine on the formed film.

  The content of the polymerization initiator is 0.1 parts by weight with respect to the compound component of the film forming material (the above silicon compound and the monomer component described later) and other components (if included) other than the solvent described below. It can be set to -15 weight part. Preferably it is 0.2 weight part-10 weight part, More preferably, it is 0.5 weight part-8 weight part. When the content is less than 0.1 parts by weight, there is a possibility that the curing rate and film strength of the film-forming material cannot be sufficiently obtained. When the content is more than 15 parts by weight, the film-forming material is being stored. This is because there is a possibility of component precipitation and decrease in coatability.

  The film-forming material contains a monomer component having a carbon-carbon unsaturated bond and not containing a silicon atom as the third component. The kind of the functional group containing a carbon-carbon unsaturated bond in the monomer is not particularly limited. For example, a monomer containing an acrylic group or a methacryl group can be used. As the monomer of the third component, monofunctional or bifunctional or higher acrylic and methacrylic acid esters can be suitably used.

  As the monomer of the third component, for example, phenoxy glycol (meth) acrylate, phenoxyethylene glycol (meth) acrylate, 2-phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, behenyl (meth) acrylate, benzyl (meth) acrylate, 1-adamantyl (meth) acrylate, isobornyl (meth) acrylate , Tridecyl (meth) acrylate, lauryl (meth) acrylate, octoxypolyethylene glycol (meth) acrylate, 2-hydroxy-3-phenoxy Propyl (meth) acrylate, isostearyl (meth) acrylate, lauryl (meth) acrylate, polyethylene glycol di (meth) acrylate, ethoxylated bisphenol A di (meth) acrylate, propoxylated bisphenol A di (meth) acrylate, 1,10 -Decanediol di (meth) acrylate, cyclodecane dimethanol di (meth) acrylate, ethoxylated-2-methyl-1,3-propanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,4-butane Diol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 2,2,3,3,4,4,5,5-octafluoro-1,6-hexyl di (meth) acrylate, 2-hydroxy-3 -Acrylo Xylpropyl (meth) acrylate, ethylene di (meth) acrylate, propoxylated ethoxylated bisphenol A di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, dipropylene Glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, Tricyclodecane dimethanol di (meth) acrylate, tricyclo [5.2.1.0 (2,6)] decandimethanol (meth) acrylate, ethoxylated isocyanuric acid tri (meth) Acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate , Ditrimethylolpropane tetra (meth) acrylate, propoxylated pentaerythritol tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, dicyclopentenyl ( (Meth) acrylate, 1,4-cyclohexanedimethanol di (meth) acrylate, 1,4-benzenedimethanol Di (meth) acrylate, hydrogenated bisphenol A di (meth) acrylate, 1,3-adamantane diol di (meth) acrylate, glycerin di (meth) acrylate, glycerin mono (meth) acrylate. In addition, (meth) acrylate represents a methacrylate.

The monomer of the third component is not limited to the above, and other commercially available products can be used as appropriate. In addition, a plurality of types of monomers can be used in combination.
The film-forming material is a solvent that dissolves other components such as the above-described first to third components (silicon compound, polymerization initiator and monomer component) and other components described later (if included) as the fourth component. including. When the solvent is solid at room temperature when the first to third components and other components described below are mixed, and the mixture has a solid content and does not become a solution, the solid content is dissolved. A coating film can be formed. Even if the mixture is in the form of a solution, a solvent can be used for the purpose of dilution even when the viscosity is high and it is difficult to apply the target film thickness.

  The solvent of the fourth component is not particularly limited as long as it can sufficiently dissolve the above first to third components and other components described later, but those having a boiling point of about 70 ° C to 200 ° C are handled. And from the viewpoint of safety. Specifically, solvents that are widely used for electronic materials are preferable, and methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve, ethyl cellosolve, γ-butyrolactone, cyclohexanone, 2-heptanone, ethyl lactate, methyl amyl ketone, methyl-3-methoxy Examples include propionate, ethyl-3-ethoxypropionate, n-butyl ether, ethyl acetate, butyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol and the like. These may be used alone or in combination of two or more.

  In addition to the above-mentioned first to fourth components, the film-forming material includes a surfactant for the purpose of improving coatability, a photosensitizer for the purpose of improving sensitivity, and an improvement in storage stability. An additive such as a polymerization inhibitor can also be contained in the mixture. Additives can be added to the film-forming material as necessary, and various types can be used depending on the purpose. The additive may be a single type or a combination of multiple types.

Then, an example of the pattern formation method by the imprint method using the film forming material which has the above components is demonstrated.
In pattern formation by the imprint method, first, a film forming material is applied onto a substrate using a coating method such as a dip coating method, a spray method, or a spin coating method. From the viewpoint of film thickness uniformity, the spin coating method is preferable.

  The film thickness of the film forming material to be applied can be selected depending on the application of the film formed from the film forming material. For example, the film forming material is applied in a thickness range of 0.05 μm to 10 μm. When the film forming material is thinner than 0.05 μm, when the solvent evaporates from the film forming material (coating film) and pinholes are generated, the pinholes have the resolution of the pattern to be formed. This is because there is a possibility of influence. In addition, in the film forming material having the above-described component structure, it may not be easy to apply the film forming material thicker than 10 μm, but it is possible to use a method such as viscosity adjustment or repeating the application a plurality of times. If present, the film-forming material may be applied thicker than 10 μm.

  After the film forming material is applied on the substrate, baking may be performed. When the applied film forming material contains a solvent (fourth component), it is preferable to perform such baking. In this case, the baking temperature can be set based on the type of solvent contained in the film forming material. The baking temperature is preferably set to be equal to or higher than the boiling point of the solvent, and is set to 50 ° C. to 180 ° C., preferably 70 ° C. to 140 ° C., depending on the type of the solvent. The baking time is not particularly limited, but is set to 10 seconds to 180 seconds, preferably 30 seconds to 90 seconds.

  After forming the film-forming material on the substrate as described above, for example, if the film-forming material has a photocurable component structure, the mold is pressed against the film-forming material exhibiting flexibility, In this state, light such as ultraviolet rays is irradiated to cure the film forming material. Also, if the film-forming material formed on the substrate has an electron beam curable component structure, the mold is pressed against the soft film-forming material, and the electron beam is irradiated in that state to form the film. Harden the material. For example, light or an electron beam passes through a mold and irradiates the film forming material. In this case, the mold is formed using a material that transmits light and an electron beam.

  When the film-forming material is irradiated with light or an electron beam, the polymerization reaction of the first component compound and the third component compound is started by the polymerization initiator (second component). Here, the first component is a silicon compound having a carbon-carbon unsaturated bond and a silicon atom to which no alkoxy group is bonded, and the third component has a carbon-carbon unsaturated bond and contains a silicon atom. There are no compounds (monomers). In the polymerization reaction, polymerization between the first component and the third component in the film-forming material containing the first component compound and the third component compound having a carbon-carbon unsaturated bond, the first component compound Polymerization in between, polymerization between compounds of the third component, etc. may proceed. As the polymerization reaction proceeds, the film-forming material pressed against the mold is cured, and a film on which the uneven pattern of the mold is transferred is formed on the substrate.

  As described above, a silicon compound having a silicon atom to which no alkoxy group is bonded is used as the first component of the film forming material. On the other hand, when a silicon compound having a silicon atom to which an alkoxy group is bonded is used, for example, a polymerization reaction as shown in the following formula (5) easily proceeds.

  An alkoxysilane such as the formula (5) in which an alkoxy group is bonded to a silicon atom is easily hydrolyzed at the alkoxy group portion to form a siloxane bond to become a high molecular siloxane polymer. When a silicon compound having a silicon atom to which an alkoxy group is bonded is used, in addition to the carbon-carbon unsaturated bond portion, the alkoxy group portion also serves as a polymerization reaction point, making the reaction control difficult and storage stability. The possibility of incurring a decline in sex occurs. From such a point of view, a silicon compound having a silicon atom to which no alkoxy group is bonded is used as the first component silicon compound of the film forming material.

  After the formation of the film on which the concave / convex pattern of the mold is transferred, the mold is separated from the film (release). The film-forming material contains a predetermined silicon compound (first component), and the film formed from the film-forming material contains such a silicon compound, thereby preventing the mold from adhering to the film. It can be pulled apart.

Hereinafter, the film forming material and the pattern forming method using the imprint method using the same will be described more specifically with reference to examples.
[Example 1]
<Preparation of film forming material for photoimprint>
As a film forming material, a film forming material for optical imprinting and a comparative material thereof were prepared. Table 1 shows the compositions (components) of the film-forming materials A to D for optical imprint and the film-forming materials (comparative materials) E to H used for the evaluation. In addition, the numerical value of Table 1 represents the weight part of each component contained.

  In Table 1, the compound a as the first component is a silicon compound represented by the following formula (6).

  In Table 1, the first component compound b is a silicon compound represented by the following formula (7). In addition, n is an integer of 0-5.

  As film-forming materials A to D and comparative materials E to H, each compound shown in Table 1 is mixed in each part by weight shown in Table 1, and filtered through a 0.5 μm membrane filter to prepare each composition. did.

<Formation of film forming material on substrate>
First, HMDS was spin-coated on a 6-inch wafer serving as a substrate, and then baked on a hot plate at 110 ° C. for 2 minutes to perform surface treatment for improving the adhesion of the coating. Next, each of the film forming materials A to D and the comparative materials E to H were formed (film formation) with a film thickness of 3 μm on the substrate after the surface treatment by spin coating. For the film-forming material D and the comparative material H containing polyethylene glycol monomethyl ether acetate (PGMEA) as the fourth component solvent, baking was performed for 1 minute on a 110 ° C. hot plate after coating.

<Mold release processing>
Prepare a quartz mold with a 1 μm, 2 μm, 3 μm, and 5 μm line-and-space (L & S) concavo-convex pattern, first wash the surface of the concavo-convex pattern side with ethanol, and bake on a hot plate at 90 ° C. for 1 minute. And then left to cool. Next, the mold was left in a saturated atmosphere of TMSDMA for 1 hour, and baked on a hot plate at 110 ° C. for 1 minute to obtain a mold surface treatment (mold release treatment (water repellent treatment)).

The same treatment was performed using a mold having no uneven pattern, and the improvement of the water repellency of the mold by this mold release treatment was confirmed in advance.
<Imprint>
The mold subjected to the mold release treatment and the substrate (6 inch wafer) on which the film forming materials A to D and the comparative materials E to H were formed were set in a predetermined imprint apparatus. Then, while reducing the pressure to -25 kPa or less, the mold was pressed against each of the film forming materials A to D and the comparative materials E to H at a pressure of 500 N, and exposed for 1 minute with an LED (Light Emitting Diode) lamp having a wavelength of 375 ± 5 nm. By this exposure, each film forming material A to D and comparative materials E to H were cured. After the exposure, pressurization was stopped and the mold was pulled upward, and the L & S pattern formed on the mold was transferred to obtain films formed from the respective film forming materials A to D and comparative materials E to H.

[Example 2]
<Evaluation of pattern defect and mold adhesion>
The peeling of the pattern formed on the film on the substrate obtained in Example 1 (pattern defect) and the adhesion of the film to the surface of the mold used (mold adhesion) were observed with an optical microscope. The results are shown in Table 2.

  In the column of “Release treatment” in Table 2, “Yes” indicates the case where the mold subjected to the above release treatment is used, and “None” indicates the case where the mold not subjected to the above release treatment is used. ". In the “pattern defect” column of Table 2, “OK” is displayed when no pattern defect is observed, and the L & S pattern with the pattern defect is displayed when a pattern defect is recognized. Yes. For example, “1-5 μmL & S” represents that a pattern defect was observed in each L & S pattern of 1 μm, 2 μm, 3 μm, and 5 μm. Further, in the column of “Mold Adhesion” in Table 2, “OK” indicates that mold adhesion is not recognized, and “NG” indicates that mold adhesion is recognized.

  When the film forming materials A to D containing the first component were used, no pattern defect was confirmed regardless of the presence or absence of mold release treatment. Further, when the film forming materials A to D containing the first component were used, mold adhesion was not confirmed.

  On the other hand, even when the comparative materials E to H not containing the first component were used, pattern defects and mold adhesion were not confirmed when the mold subjected to the release treatment was used. On the other hand, when the comparative materials E to H not containing the first component are used and the mold release process is not performed, pattern defect and mold adhesion are confirmed in any of the comparative materials E to H. It was done. The pattern defect tends to occur when the pattern width is large, and the pattern defect was observed in the L & S pattern of 5 μm in any composition of the comparative materials E to H.

<Evaluation of mold release treatment>
For the film forming material A and the comparative material E, evaluation of mold adhesion was performed when imprinting was repeated continuously. The results are shown in Table 3.

  In the column of “Release treatment” in Table 3, “Yes” indicates the case where the mold subjected to the above release treatment is used, and “None” indicates the case where the mold not subjected to the above release treatment is used. ". In addition, “1”, “5”, and “10” shown in the “Number of prints” column of Table 3 indicate the number of imprints that were continuously performed. The case where it is not recognized is expressed as “OK”, and the case where the mold adhesion is recognized is expressed as “NG”.

  When the film-forming material A containing the first component was used, mold release was not recognized even when imprinting was carried out 10 times continuously when the mold was subjected to a mold release treatment. Moreover, even if the mold was not subjected to mold release treatment, imprinting was performed five times in succession, and mold adhesion was not recognized.

  On the other hand, when the film forming material E that does not contain the first component is used, if the mold is subjected to the mold release process, the adhesion of the mold can be suppressed if the imprint is performed once. In the 10th and 10th imprints, mold adhesion was observed. When the mold release treatment was not performed, mold adhesion was already recognized by the first imprint.

  Although the effect of suppressing the adhesion of the film to the mold is obtained by the mold release treatment, there is a limit to the effect when imprinting is repeated continuously. By including a component that improves the mold releasability of the film forming material itself, that is, the above-mentioned first component, it is possible to effectively adhere the film to the mold even when imprinting is performed repeatedly using the same mold. And high-resolution patterning can be performed.

  As mentioned above, although the Example of the film formation material and the pattern formation method by the imprint method were described, the composition of a film formation material and the pattern formation method using the same are not limited to this example.

Regarding the embodiment described above, the following additional notes are further disclosed.
(Additional remark 1) The component containing the compound which has a carbon-carbon unsaturated bond,
A polymerization initiator for initiating a polymerization reaction of the compound,
A film-forming material comprising a silicon compound having a carbon-carbon unsaturated bond and a silicon atom to which no alkoxy group is bonded as the compound.

  (Supplementary Note 2) The silicon compound has the formula (8)

[Wherein, s is an integer of 0 to 5, and Q _{1 to} Q ₃ each have a structure represented by Q in the formula (9), and a structure represented by Q in the formula (9). Otherwise, it is an alkyl group having 1 to 5 carbon atoms.

(Wherein t is an integer of 0 to 5)]. The film forming material according to supplementary note 1, wherein the film forming material is a silicon compound.
(Supplementary Note 3) The silicon compound has the formula (10)

(In the formula, n is an integer of 0 to 5, and R1 to R3 each have at least one structure represented by R in formula (11) and not a structure represented by R in formula (11). Is an alkyl group having 1 to 5 carbon atoms.

The film forming material according to supplementary note 1, wherein the film forming material is a silicon compound represented by the following formula:
(Additional remark 4) The film forming material in any one of additional remark 1 thru | or 3 which contains the monomer which does not contain a silicon atom and has a carbon-carbon unsaturated bond as said compound.

(Additional remark 5) The film forming material in any one of Additional remark 1 thru | or 4 further including the solvent in which the said compound and the said polymerization initiator melt | dissolve.
(Additional remark 6) The said polymerization initiator starts the polymerization reaction of the said compound by irradiation of an energy beam, The film formation material in any one of Additional remark 1 thru | or 5 characterized by the above-mentioned.

(Additional remark 7) The said energy beam is light or an electron beam, The film formation material of Additional remark 6 characterized by the above-mentioned.
(Appendix 8) Forming a film forming material on a substrate;
A step of pressing a mold having a concavo-convex pattern against the formed film-forming material to form a reverse pattern of the concavo-convex pattern;
Using the film forming material on which the reverse pattern is formed, forming a film having the reverse pattern;
Separating the mold from the formed coating,
The film forming material formed on the substrate is:
A component comprising a compound having a carbon-carbon unsaturated bond;
A polymerization initiator for initiating a polymerization reaction of the compound,
The pattern formation method characterized by including the silicon compound which has a carbon-carbon unsaturated bond and the silicon atom to which an alkoxy group does not couple | bond as said compound.

(Additional remark 9) The said polymerization initiator starts the polymerization reaction of the said compound by irradiation of an energy beam,
The pattern forming method according to appendix 8, wherein the film is formed by the polymerization reaction.

(Appendix 10) The mold is formed using a material that transmits the energy beam,
The pattern forming method according to appendix 9, wherein when the energy beam is irradiated, the film forming material on which the reverse pattern is formed is irradiated with the energy beam through the mold.

  (Additional remark 11) Before the process of forming the said film formation material on the said board | substrate, the process of performing the surface treatment for making the said film adhere to the said board | substrate is included in any one of Additional remark 8 thru | or 10 characterized by the above-mentioned. The pattern formation method as described.

  (Supplementary note 12) Supplementary note 8 includes a step of performing a surface treatment for suppressing adhesion of the coating to the mold before the step of pressing the mold against the coating-forming material to form the reverse pattern. The pattern formation method in any one of thru | or 11.

DESCRIPTION OF SYMBOLS 1 Substrate 1c Surface treatment layer 2 Film formation material 2a Film 3 Mold 3a Concavity and convexity pattern 3b Reverse pattern 3c Surface treatment layer 10 Stage

Claims (7)

A component comprising a compound having a carbon-carbon unsaturated bond;
A polymerization initiator for initiating a polymerization reaction of the compound,
As the compound, carbon - see containing carbon unsaturated bonds, a silicon compound having a silicon atom alkoxy group is not bound,
The silicon compound has the formula (1)

(In the formula, n is an integer of 0 to 5, and R1 to R3 each have a structure represented by R in the formula (2) and not a structure represented by R in the formula (2). Is an alkyl group having 1 to 5 carbon atoms.

A film-forming material characterized by being represented by: A component comprising a compound having a carbon-carbon unsaturated bond;
A polymerization initiator for initiating a polymerization reaction of the compound,
As the compound, carbon - see containing carbon unsaturated bonds, a silicon compound having a silicon atom alkoxy group is not bound,
The silicon compound has the formula (3)

It is represented by the film formation material characterized by these. As the compound does not contain a silicon atom, and a carbon - film-forming material of claim 1 or 2, characterized in that it comprises a monomer having a carbon-carbon unsaturated bond. Film-forming material according to any one of claims 1 to 3, further comprising a solvent in which the compound and the polymerization initiator is dissolved. The polymerization initiator, the energy beam film-forming material according to any one of claims 1 to 4, characterized in that to initiate the polymerization reaction of the compound by irradiation of. Forming a film forming material on the substrate;
A step of pressing a mold having a concavo-convex pattern against the formed film-forming material to form a reverse pattern of the concavo-convex pattern;
Using the film forming material on which the reverse pattern is formed, forming a film having the reverse pattern;
Separating the mold from the formed coating,
The film forming material formed on the substrate is:
A component comprising a compound having a carbon-carbon unsaturated bond;
A polymerization initiator for initiating a polymerization reaction of the compound,
As the compound, carbon - see containing carbon unsaturated bonds, a silicon compound having a silicon atom alkoxy group is not bound,
The silicon compound has the formula (4)

(In the formula, n is an integer of 0 to 5, and R1 to R3 have at least one structure represented by R in the formula (5) and are not a structure represented by R in the formula (5). Is an alkyl group having 1 to 5 carbon atoms.

The pattern formation method characterized by the above-mentioned . Forming a film forming material on the substrate;
A step of pressing a mold having a concavo-convex pattern against the formed film-forming material to form a reverse pattern of the concavo-convex pattern;
Using the film forming material on which the reverse pattern is formed, forming a film having the reverse pattern;
Separating the mold from the formed coating,
The film forming material formed on the substrate is:
A component comprising a compound having a carbon-carbon unsaturated bond;
A polymerization initiator for initiating a polymerization reaction of the compound,
As the compound, carbon - see containing carbon unsaturated bonds, a silicon compound having a silicon atom alkoxy group is not bound,
The silicon compound has the formula (6)

The pattern formation method characterized by these.

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