JP4742665B2 - Method of manufacturing processed substrate processed by etching - Google Patents

Description

  The present invention relates to a simple manufacturing method of a processed substrate in which a substrate and a resist film excellent in etching resistance on which a highly accurate desired resist pattern is formed are integrated.

  In recent years, a substrate having a resist film on which a desired resist pattern is formed is obtained by transferring a mold pattern to a resist film, and then the resist film of the substrate is made to function as a mask, followed by etching treatment. Attention has been focused on a method for obtaining a base material etched by the above-mentioned method. This method is called nanoimprint lithography (see Patent Document 1, Patent Document 2, etc.).

  As a curable resist composition for forming a resist film in nanoimprint lithography, a composition containing a photopolymerizable monomer that does not contain a fluorine-containing surfactant is known. However, the resist film formed from the composition has insufficient releasability from the mold and is difficult to peel off from the mold surface. A release agent is applied to the mold surface in order to perform the peeling smoothly, but the accuracy of the resist pattern tends to decrease due to uneven thickness of the release agent layer. Moreover, when using a mold continuously, it is necessary to apply | coat a mold release agent repeatedly and production efficiency is low.

JP-T-2004-504718 Special Table 2002-539604

  An object of the present invention is to provide a method for manufacturing a processed substrate in which a substrate and a resist film on which a desired resist pattern is formed are integrated with high accuracy and high production efficiency.

The present invention provides the following inventions.
[1]: By performing the following step 1, the following step 2, and the following step 3 in order, a processed substrate in which the substrate and the resist film on which the desired resist pattern is formed is obtained is obtained. A method of manufacturing an etched processed substrate, wherein the substrate is etched by etching the surface on which the resist film is formed.
Step 1: A nonionic fluorine-containing surfactant and a polymerizable monomer having a ring structure, or a polymerizable monomer forming a ring structure by polymerization, by combining a substrate and a mold having a reverse pattern of a desired resist pattern on the surface A step of sandwiching a resist composition comprising: the substrate surface and the pattern surface of the mold.
Step 2: A step of polymerizing a polymerizable monomer in the resist composition to form a resist film from the composition.
Step 3: A step of removing the mold from the resist film to obtain a processed substrate.

[2]: The production according to [1], wherein the reversal pattern of the mold having the reversal pattern on the surface is a fine pattern having a convex portion and a concave portion, and the average value of the interval between the convex portions is 1 nm to 500 μm. Method.
[3] The production method according to [1] or [2], wherein the resist composition is a resist composition containing a polymerization initiator.
[4]: fluorinated surfactant, produced how according to any one of fluorine atom content of 10 to 70 wt% of the fluorinated surfactant [1] to [3].

  In the present invention, a resist composition containing a fluorine-containing surfactant and a polymerizable monomer having a ring structure or a polymerizable monomer that forms a ring structure by polymerization is used. Therefore, the resist film formed from the resist composition can be smoothly peeled off from the mold and has excellent etching resistance. Therefore, highly accurate nanoimprint lithography can be efficiently performed by the present invention.

  In the present invention, the compound represented by the formula (1) is represented as Compound 1. Compounds represented by other formulas are also represented in the same manner.

  In the production method of the present invention, a combination of a substrate and a mold having a reverse pattern of a desired resist pattern on the surface, a fluorine-containing surfactant, a polymerizable monomer having a ring structure, or polymerization for forming a ring structure by polymerization A step of sandwiching a resist composition containing a polymerizable monomer between the substrate surface and the pattern surface of the mold (step 1), polymerizing the polymerizable monomer in the resist composition, and then forming a resist film from the composition Step (step 2) of forming the substrate and a step of removing the mold from the resist film to obtain a processed substrate in which the substrate and the resist film on which the desired resist pattern is formed (step 3) are sequentially performed. The operating conditions in step 1, step 2, and step 3 will be described later.

  Since the resist composition in the present invention contains a fluorine-containing surfactant, a resist film excellent in releasability is formed in Step 2. Therefore, peeling in step 3 proceeds smoothly, and a resist film on which a desired resist pattern with high accuracy is formed is obtained.

The fluorine-containing surfactant is preferably a fluorine-containing surfactant having a fluorine atom content of 10 to 70% by mass.
Fluorinated surfactants, anionic fluorinated surfactant having a R ^F group and an anionic group, a cationic fluorine-containing surfactant having a R ^F group and a cationic group, R ^F group, a cationic group, and amphoteric fluorinated surfactant having an anionic group, or a nonionic fluorinated surfactant having a R ^F group is preferred. However, ^RF is a fluorine-containing organic group and is preferably a polyfluoroalkyl group having 1 to 20 carbon atoms or a perfluoro (polyoxyalkylene) group having 1 to 20 carbon atoms (the same applies hereinafter). Since the fluorine-containing surfactant has good compatibility in the resist composition and dispersibility in the resist film , the nonionic fluorine-containing surfactant is selected in the present invention . The fluorine-containing surfactant may be water-soluble or fat-soluble.

  The anionic fluorine-containing surfactant is preferably a polyfluoroalkyl carboxylate, a polyfluoroalkyl phosphate, or a polyfluoroalkyl sulfonate. These cationic surfactants are Surflon S-111 (trade name, manufactured by Seimi Chemical Co., Ltd.), Florard FC-143 (trade name, manufactured by 3M), Megafark F-120 (trade name, manufactured by Dainippon Ink Industries, Ltd.). ) Etc.

  The cationic fluorine-containing surfactant is preferably a trifluoroammonium salt of polyfluoroalkylcarboxylic acid or a trimethylammonium salt of polyfluoroalkylsulfonic acid amide. These cationic surfactants are Surflon S-121 (trade name, manufactured by Seimi Chemical Co., Ltd.), Florard FC-134 (trade name, manufactured by 3M), Megafark F-150 (trade name, manufactured by Dainippon Ink Industries, Ltd.). ) Etc.

  As the amphoteric fluorine-containing surfactant, polyfluoroalkyl betaine is preferable. These amphoteric surfactants include Surflon S-132 (trade name, manufactured by Seimi Chemical Co., Ltd.), Florard FX-172 (trade name, manufactured by 3M), Megafark F-120 (trade name, manufactured by Dainippon Ink Industries, Ltd.) Etc. are easily available.

The nonionic fluorine-containing surfactant is preferably a polyfluoroalkylamine oxide, a polyfluoroalkyl / alkylene oxide adduct, or a polymer having an R ^F group, and a polyfluoroalkyl / alkylene oxide adduct or a polymer having an R ^F group Is particularly preferred.

Examples of the polyfluoroalkyl / alkylene oxide adduct include F (CF ₂ ) ₆ CH ₂ CH ₂ O (CH ₂ CH ₂ O) ₁₀ H, F (CF ₂ ) ₈ CH ₂ CH (OH) CH ₂ O (CH _{2 CH 2 O) 10 H, F} (CF 2) 8 CH 2 CH (OH) CH 2 O (CH 2 CH 2 O) 10 CH 2 CH (OH) CH 2 (CF 2) 8 F , and the like.

Polymers having a R ^F group, the polymer comprising monomer units based on a monomer having an R ^F group is preferred. As the monomer, a monomer containing an R ^F group and an epoxy group, a vinyl group, an allyl group, an acryloyl group, or a methacryloyl group is preferable, and a monomer containing an R ^F group and an acryloyl group or a methacryloyl group is particularly preferable. .

As a specific example of the monomer having an R ^F group, fluoro (meth) acrylate is preferable. However, (meth) acrylate is a general term for acrylate and methacrylate (the same applies hereinafter). Examples of the fluoro (meth) acrylate include the following compounds (where m1 to m6 are each independently an integer of 0 to 10, j5 and j6 are each independently an integer of 1 to 10, n1, n2, n5 And n6 each independently represents an integer of 1 to 20.)
CH ₂ = CHCOO (CH ₂ ) _m1 (CF ₂ ) _n1 F,
_{CH 2 = C (CH 3)} COO (CH 2) m2 (CF 2) n2 F,
_{CH 2 = CHCOO (CH 2)} m3 CF (CF 3) 2,
_{CH 2 = C (CH 3)} COO (CH 2) m4 CF (CF 3) 2,
_{CH 2 = CHCOO (CH 2)} m5 N (CH 2) j5 SO 2 (CF 2) n5 F,
_{CH 2 = C (CH 3)} COO (CH 2) m6 N (CH 2) j6 SO 2 (CF 2) n6 F.

Polymers having a R ^F group is a monomer containing no fluorine atom other than the monomer having a R ^F group (hereinafter, simply. That other monomer) may contain monomer units based on. The other monomer is preferably a (meth) acrylate containing no fluorine atom. The (meth) acrylate may be an aromatic (meth) acrylate or an aliphatic (meth) acrylate.

  Examples of aromatic (meth) acrylates include phenoxyethyl acrylate, benzyl acrylate, and naphthyl acrylate. Examples of aliphatic (meth) acrylates include chain aliphatic monofunctional (meth) acrylates, cycloaliphatic monofunctional (meth) acrylates, and polyfunctional (meth) acrylates.

  As chain aliphatic monofunctional (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) Acrylate, lauryl (meth) acrylate, ethoxyethyl (meth) acrylate, methoxyethyl (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (Meth) acrylate, 4-hydroxybutyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, dimethylaminoethyl Meth) methacrylate.

  Specific examples of the cycloaliphatic monofunctional (meth) acrylate include adamantyl (meth) acrylate, methyladamantyl (meth) acrylate, hydroxyadamantyl (meth) acrylate, norbornyl (meth) acrylate, and the like.

  Specific examples of the polyfunctional (meth) acrylate include 1c-butanediol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaaerythritol triacrylate, diester Examples include pentaerythritol hexaacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, polyoxyethylene glycol diacrylate, and tripropylene glycol diacrylate.

  Other monomers include alkyl vinyl ethers (ethyl vinyl ether, propyl vinyl ether, isobutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, etc.), alkyl vinyl esters (vinyl acetate, vinyl propionate, vinyl (iso) butyrate, vinyl valerate, Vinyl cyclohexanecarboxylate), vinyl benzoate, alkyl allyl ether (ethyl allyl ether, propyl allyl ether, (iso) butyl allyl ether, cyclohexyl allyl ether, etc.), alkyl allyl ester (ethyl allyl ester, propyl allyl ester, Isobutyl allyl ester, etc.) may also be used.

The weight average molecular weight of the polymer having an ^{R F} group, from the viewpoint of compatibility with the monomers, preferably from 500 to 500,000, particularly preferably 1,000 to 10,000.

  These nonionic surfactants are also Surflon S-145 (trade name, manufactured by Seimi Chemical), Surflon S-393 (trade name, manufactured by Seimi Chemical), Surflon KH-20 (trade name, manufactured by Seimi Chemical) , Surflon KH-40 (trade name, manufactured by Seimi Chemical Co., Ltd.), Florard FC-170 (trade name, manufactured by 3M), Fluorard FC-430 (trade name, manufactured by 3M), Megafark F-141 (trade name, large (Manufactured by Nippon Ink Industries Co., Ltd.) etc.

  The content of the fluorine-containing surfactant in the resist composition is preferably 0.01 to 10% by mass, particularly preferably 0.1 to 5% by mass. Within this range, it is easy to adjust the resist composition, and a resist film excellent in releasability can be obtained.

  The resist composition in the present invention includes a polymerizable monomer having a ring structure (hereinafter also referred to as a cyclic monomer) or a polymerizable monomer that forms a ring structure by polymerization (hereinafter also referred to as a cyclized monomer). The cyclic monomer and the cyclized monomer are collectively referred to as a ring-forming monomer. Since the resist film in the present invention contains a polymer having a ring structure formed by polymerization of a ring-forming monomer, it has excellent etching resistance. The reason is not necessarily clear, but it is considered that a polymer having a ring structure is likely to retain a bulky structure derived from the ring structure even if the carbon-carbon bond is broken by etching.

  From the viewpoint of etching resistance, the ring-forming monomer preferably does not contain a fluorine atom. From the viewpoint of compatibility with the fluorine-containing surfactant, the ring-forming monomer preferably contains a fluorine atom. When the ring-forming monomer contains a fluorine atom, the fluorine atom content of the ring-forming monomer is preferably 10 to 70% by mass. Further, from the viewpoint of improving the adhesion with the substrate, the ring-forming monomer preferably contains a functional group (preferably a hydroxyl group).

The cyclic monomer is preferably a polymerizable monomer having a polymerizable group and a ring structure.
The polymerizable group is preferably an oxirane group or a polymerizable carbon-carbon double bond, more preferably a vinyl group, an allyl group, an acryloyl group, or a methacryloyl group, and particularly preferably an acryloyl group or a methacryloyl group.

  The ring of the ring structure may be a hydrocarbon ring or a heterocycle, and is preferably a hydrocarbon ring. The ring may be a saturated ring or an unsaturated ring. The unsaturated ring may be a conjugated ring.

  The hydrocarbon ring is preferably a monocyclic hydrocarbon, a condensed polycyclic hydrocarbon, a bridged ring hydrocarbon, or a spiro ring hydrocarbon, more preferably a condensed polycyclic hydrocarbon or a bridged ring hydrocarbon, a cholesterol ring, an adamantane A ring or a norbornane ring is particularly preferable. However, the adamantane ring means a bridged ring represented by the following (1), and the norbornane structure means a bridged ring represented by the following (2).

  The hydrocarbon ring includes a silicon atom, a sulfur atom, an oxygen atom, a nitrogen atom, a boron atom, a phosphorus atom, a halogen atom (a chlorine atom, a bromine atom, an iodine atom, etc.), etc. as atoms other than the atoms constituting the ring. May be included.

  Specific examples of the cyclic monomer include the following compounds.

As the cyclized monomer, CF ₂ = CFOCF ₂ CF ₂ CF = CF ₂ , CF ₂ = CFOCF (CF ₃ ) CF ₂ CF = CF ₂ , CF ₂ = CFOCF ₂ CF (CF ₃ ) CF═CF ₂ , CF _{2 = CFCF 2 CF = CF 2,} CF 2 = CFCF 2 CH = CH 2, CF 2 = CFCF 2 C (CF 3) (OH) CH 2 CH = CH 2, CF 2 = CFCF 2 C (CF 3) (OH _{) CH = CH 2, CF 2} = CFCH 2 CH (CH 2 C (CF 3) 2 OH) CH 2 CH = CH 2, CF 2 = CFCH 2 CH (CH 2 C (CF 3) 2 OH) CH = CH _{2, CF 2 = CFCH 2 CH} (C (CF 3) 2 OH) CH 2 CH = CH 2, CF 2 = CFCH 2 CH (C (CF 3) 2 OH) CH = CH 2 and fluorine Hara Bis- (2,3-epoxypropoxy) ether, bis [2- (t-butoxycarbonyl) allyl] ether, 1b: 5,6-dianhydro-D-mannitol, N-hexyl-N- Examples thereof include cyclized monomers containing no fluorine atom, such as allyl-2- (ethoxycarbonyl) allylamine.

  In the resist composition, a polymerizable monomer other than the ring-forming monomer (hereinafter referred to as other polymerizable monomer) may be used. The other polymerizable monomer may be another polymerizable monomer containing a fluorine atom or another polymerizable monomer containing no fluorine atom.

  Examples of the other polymerizable monomer containing a fluorine atom include fluorovinyl ether, fluoroallyl ether, fluorodiene, fluoro (meth) acrylate, and fluoroolefin.

Specific examples of other polymerizable monomer containing a fluorine atom include CF ₂ ═CFO (CF ₂ ) ₃ COOCH ₃ , CH ₂ ═CHCOO (CH ₂ ) ₂ (CF ₂ ) ₁₀ F, CH ₂ ═CHCOO (CH ₂ ) ₂ (CF ₂ ) ₈ F, CH ₂ = CHCOO (CH ₂ ) ₂ (CF ₂ ) ₆ F, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (CF ₂ ) ₁₀ F, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (CF ₂ ) ₈ F, CH ₂ ═C (CH ₃ ) COO (CH ₂ ) ₂ (CF ₂ ) ₆ F, CH ₂ ═CHCOOCH ₂ (CF ₂ ) ₇ F, CH ₂ = C (CH ₃ ) COOCH ₂ (CF ₂ ) ₇ F, CH ₂ = CHCOOCH ₂ CF ₂ CF ₂ H, CH ₂ = CHCOOCH ₂ (CF ₂ CF ₂ ) ₂ H, CH ₂ = CHCOOCH ₂ (CF _{2 CF 2) 4 H, CH 2} = C (CH 3) COOCH 2 (CF 2 CF 2) H, _{H 2 = C (CH 3)} COOCH 2 (CF 2 CF 2) 2 H, CH 2 = C (CH 3) COOCH 2 (CF 2 CF 2) 4 H, CH 2 = CHCOOCH 2 CF 2 OCF 2 CF 2 OCF _{3, CH 2 = CHCOOCH 2 CF} 2 O (CF 2 CF 2 O) 3 CF 3, CH 2 = C (CH 3) COOCH 2 CF 2 OCF 2 CF 2 OCF 3, CH 2 = C (CH 3) COOCH 2 _{CF 2 O (CF 2 CF 2} O) 3 CF 3, CH 2 = CHCOOCH 2 CF (CF 3) OCF 2 CF (CF 3) O (CF 2) 3 F, CH 2 = CHCOOCH 2 CF (CF 3) O _{(CF 2 CF (CF 3)} O) 2 (CF 2) 3 F, CH 2 = C (CH 3) COOCH 2 CF (CF 3) OCF 2 CF (CF 3) O (CF 2) 3 F, CH 2 _{= C (CH 3) COOCH 2} CF (CF 3) O (CF 2 CF (C _{3) O) 2 (CF 2} ) 3 F, CH 2 = CFCOOCH 2 CH (OH) CH 2 (CF 2) 6 CF (CF 3) 2, CH 2 = CFCOOCH 2 CH (CH 2 OH) CH 2 (CF _{2) 6 CF (CF 3)} 2, CH 2 = CFCOOCH 2 CH (OH) CH 2 (CF 2) 10 F, CH 2 = CFCOOCH 2 CH (CH 2 OH) CH 2 (CF 2) 10 F, the following compound (However, p1-p4 shows the integer of 3-10 each independently. q1 and q2 each independently represent 0 or an integer of 1 to 6. Cy ^F represents a perfluoro (1,4-cyclohexylene) group. ).

  Other polymerizable monomers that do not contain fluorine atoms include (meth) acrylate, (meth) acrylic acid, vinyl ether, vinyl ester, allyl ether, allyl ester, olefin (ethylene, propylene, butene, butadiene, etc.), and anhydrous maleic acid. An acid, vinylene carbonate, etc. are mentioned.

Specific examples of (meth) acrylates include the following compounds.
Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl acrylate, lauryl acrylate, ethoxyethyl acrylate, methoxyethyl acrylate, glycidyl acrylate, tetrahydro Furfuryl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl (meth) acrylate, N, N-diethylaminoethyl acrylate, N, N-dimethylaminoethyl acrylate, N-vinylpyrrolidone, dimethylamino Monofunctional (meth) acrylates such as ethyl methacrylate.

  1c-butanediol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaaerythritol triacrylate, dipentaerythritol hexaacrylate, diethylene glycol diacrylate, neopentyl glycol Monofunctional (meth) acrylates such as diacrylate, polyoxyethylene glycol diacrylate, and tripropylene glycol diacrylate.

Specific examples of the vinyl ether include the following compounds.
Alkyl vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, isobutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether; vinyl benzoate.
Specific examples of the vinyl ester include the following compounds.
Alkyl vinyl esters such as vinyl acetate, vinyl propionate, vinyl (iso) butyrate and vinyl valerate.
Specific examples of allyl ether include the following compounds.
Alkyl allyl ethers such as ethyl allyl ether, propyl allyl ether, and (iso) butyl allyl ether;
Specific examples of allyl esters include the following compounds.
Alkyl allyl esters such as ethyl allyl ester, propyl allyl ester and isobutyl allyl ester;

  In the resist composition, one or more ring-forming monomers may be used. One or more ring-forming monomers may be used in combination with one or more other polymerizable monomers. When using other polymerizable monomer, the ratio of the ring-forming monomer to the total monomer is preferably 5% by mass or more and less than 100% by mass. In addition, the combination when used in combination is preferably a cyclic monomer and another polymerizable monomer containing a fluorine atom, or a cyclized monomer containing a fluorine atom and another polymerizable monomer containing no fluorine atom. In this case, it is easy to adjust the resist composition in which the monomer and the fluorine-containing surfactant are uniformly dissolved, and the resist composition is easily arranged on the substrate surface. When using the other polymerizable monomer containing a cyclic monomer and a fluorine atom, 5 mass% or more is preferable and, as for the ratio of the other polymerizable monomer containing a fluorine atom with respect to all the monomers, 20 mass% or more is especially preferable.

  Examples of the substrate in the present invention include a silicon substrate, a compound semiconductor substrate, a glass substrate, and a nonmagnetic ceramic substrate. A desired layer may be formed on the substrate. Examples of the desired layer include a silicon oxide layer, a wiring metal layer, an interlayer insulating film, a magnetic film, and an antireflection film layer. The desired layer may be formed as various wirings, circuits, and the like.

Examples of the mold in the present invention include a mold made of a non-translucent material such as a silicon wafer, SiC, and mica; and a mold made of a translucent material such as glass, polydimethylsiloxane, and transparent fluororesin.
In the case where the polymerization in step 2 is performed by light, a mold made of a translucent material is preferable. Moreover, you may use the mold made from a non-light-transmitting material using the process substrate made from a light-transmitting material. When the polymerization in the step 2 is performed by heat, a mold made of a non-translucent material may be used.

The mold in the present invention has a fine pattern which is a reverse pattern of a desired resist pattern on the surface. The fine pattern is preferably a fine pattern having convex portions and concave portions. The average value of the convex spacing (L ¹ ) in the fine pattern is preferably ¹ nm to 500 μm, particularly preferably 1 nm to 50 μm. The average value of the width (L ² ) of the convex portion is preferably 1 nm to 100 μm, and particularly preferably 10 nm to 10 μm. The average value of the height (L ³ ) of the convex portion is preferably 1 nm to 100 μm, and particularly preferably 10 nm to 10 μm.

  In the present invention, even when the minimum dimension of the fine pattern of the mold is 50 μm or less, smaller is 500 nm or less, and even smaller is 50 nm or less, the fine pattern (that is, the desired resist pattern) can be transferred to the resist film with high accuracy. The minimum dimension of a fine pattern means the minimum value among mold convex part height, mold uneven | corrugated part space | interval, and mold convex part length. The minimum of the minimum dimension is not specifically limited, 1 nm or more is preferable.

  In step 1 of the present invention, the space between the substrate surface and the mold pattern surface is preferably less than the height of the fine pattern of the mold.

As a preferable aspect of the process 1, the following process 1a, the following process 1b, and the following process 1c are mentioned.
Step 1a: A step of placing the resist composition on the surface of the processed substrate and then pressing the processed substrate and the mold so that the resist composition is in contact with the pattern surface of the mold.
In step 1a, the resist composition is arranged using a method such as a potting method, a spin coating method, a roll coating method, a casting method, a dip coating method, a die coating method, a Langmuir projet method, or a vacuum deposition method. It is preferable to coat the processed substrate surface. The resist composition is preferably coated on the entire processed substrate.

Alternatively, a resist composition having a viscosity adjusted by adding a solvent may be used to form a coating film of the resist composition on the processed substrate surface, and then the solvent may be distilled off to coat the resist composition on the processed substrate surface. The solvent is preferably a solvent having a boiling point of 80 to 200 ° C., which uniformly dissolves or disperses the resist composition. Solvents include non-fluorine organic solvents such as xylene and butyl acetate; fluorine-containing systems such as perfluoro (2-butyltetrahydrofuran), methyl (perfluoroisopropyl) ether, methyl (perfluorohexylmethyl) ether, and methyl (perfluorooctyl) ether Solvent; water.
The press pressure (gauge pressure) that is the pressure for pressing the substrate and the mold is preferably more than 0 and 10 MPa or less, and more preferably 0.1 to 5 MPa.

Step 1b: a step of placing the resist composition on the pattern surface of the mold and then pressing the processed substrate and the mold so that the surface of the processed substrate is in contact with the resist composition.
In step 1b, the resist composition is arranged using a method such as potting, spin coating, roll coating, casting, dip coating, die coating, Langmuir projet, and vacuum deposition. It is preferable to cover the pattern surface of the mold. The resist composition may be coated on the entire pattern surface or only on a part of the pattern surface.

Alternatively, a resist composition having a viscosity adjusted by adding a solvent may be used to form a coating film of the resist composition on the pattern surface, and then the solvent may be distilled off to coat the resist composition on the pattern surface. As the solvent, the same solvent as that used in the step 1a is used.
The press pressure (gauge pressure) that is the pressure for pressing the substrate and the mold is preferably more than 0 and 10 MPa or less, and more preferably 0.1 to 5 MPa.

  In step 1c, the method of filling the void with the resist composition includes a method of sucking the resist composition into the void by capillary action.

  In Step 2 of the present invention, the polymerization method of the polymerizable monomer can be appropriately determined in consideration of the physical properties of the ring-forming monomer and the type of the resist composition containing a polymerization initiator. The polymerization method is preferably a method using heat or light. A polymerization method by light irradiation using a resist composition containing a photopolymerization initiator that can be polymerized at a low temperature (0 to 60 ° C.) and can suppress volume shrinkage of the resist film is particularly preferred.

  Examples of the light irradiation method include a method of irradiating light from the light transmitting material mold side and a method of irradiating light from the light transmitting material substrate side. The light irradiated with light is preferably light having a wavelength of 200 to 400 nm, which is easily reacted with a photopolymerization initiator capable of low-temperature polymerization. Moreover, at the time of light irradiation, the entire system may be heated to accelerate the polymerization of the ring-forming monomer. The heating temperature range is preferably 300 ° C. or less, more preferably 0 to 60 ° C., and particularly preferably 25 to 50 ° C.

  In step 3 of the present invention, the temperature at which the mold is peeled from the resist film is preferably 0 to 50 ° C.

In the processed substrate (hereinafter also simply referred to as a processed substrate) obtained by steps 1 to 3 of the manufacturing method of the present invention, the substrate and a resist film having excellent etching resistance are integrated. Made to function desired resist pattern of the resist film as a mask, you produce processed substrate which has been etched by etching a substrate. In the present invention, the resist film has a desired resist pattern with high accuracy and is excellent in etching resistance, so that a processing substrate having a high accuracy pattern can be manufactured. Resist film of the substrate is you removed.

  Etching is preferably dry etching or wet etching, and dry etching is particularly preferable. Examples of dry etching include gas phase etching that reacts with gas at high temperature, plasma etching using low temperature gas plasma, reactive ion etching (RIE), ion sputter etching, ion beam etching using an ion gun, and photo etching. Can be mentioned. The removal of the resist film can be performed according to a conventional method.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these. And a fluorine atom content of the F content, and M _W a weight average molecular weight referred.

  In Examples, the following compound a1, the following compound a2, or the following compound a3 is used as a monomer having a ring structure, and the following compound c1 (F content: 57.2%) is used as another monomer containing a fluorine atom. As another monomer containing no atom, the following compound d1 or the following compound d2 was used.

As the polymerization initiator, Irgacure 651 (trade name, manufactured by Ciba Specialty Chemicals Co., Ltd.), a photopolymerization initiator, was used.
As the fluorine-containing surfactant, a polymer having a nonionic R ^F group (F content: about 30%, _Mw: about 3000) was used.

[Preparation of resist composition]
In a clean room where ultraviolet rays were cut, 0.45 g of compound a1, 0.10 g of compound d1, 0.40 g of compound d2 and 0.01 g of fluorine-containing surfactant were mixed in a vial container (internal volume 6 mL). did. Further, 0.04 g of a photopolymerization initiator was mixed to prepare a resist composition (hereinafter referred to as composition 1). In the same manner, the following composition 2, the following composition 3, and the following composition 4 were prepared.

Composition 2: A resist composition comprising 0.30 g of compound a1, 0.25 g of compound c1, 0.30 g of compound d1, 0.01 g of a fluorine-containing surfactant, and 0.04 g of a photopolymerization initiator.
Composition 3: A resist composition comprising 0.30 g of compound a2, 0.25 g of compound c1, 0.40 g of compound d1, 0.01 g of a fluorine-containing surfactant, and 0.04 g of a photopolymerization initiator.
Composition 4: A resist composition comprising 0.30 g of compound a3, 0.25 g of compound c1, 0.40 g of compound d1, 0.01 g of a fluorinated surfactant, and 0.04 g of a photopolymerization initiator.

[Example 1] Processed substrate and process substrate manufacturing example using the processed substrate (part 1)
One drop of the composition 1 is spin-coated on a silicon wafer to obtain a silicon wafer whose surface is coated with a film (film thickness 50 nm) made of the composition 1. A transparent mold (made of quartz) having a concavo-convex structure in which concave structures having a width of 400 nm and a depth of 100 nm are arranged at equal intervals of 200 nm on the surface is pressed against the coating surface of the composition 1 to bring the silicon wafer and the transparent mold to 25 ° C. Press at 0.5 MPa (gauge pressure).

  The composition 1 is subjected to a monomer polymerization reaction by irradiating light from a high pressure mercury lamp (frequency: 1.5 kHz to 2.0 kHz, dominant wavelength light: 255 nm, 315 nm, and 365 nm) for 15 seconds. When the mold is slowly peeled from the silicon wafer, a silicon wafer (processed substrate) integrated with the resist film formed from the composition 1 is obtained. A concavo-convex structure in which the concavo-convex structure of the mold is transferred with high accuracy is formed on the surface of the resist film.

Next, the processed substrate is dry-etched by RIE (reactive ion etching) using a mixed gas of O ₂ , Ar, and CF ₄ as an etching gas. The etching resistance of the resist film is almost equal to that of novolak resin. Next, the resist film on the silicon wafer is removed by ashing and the silicon wafer is acid cleaned to obtain a silicon wafer having a pattern corresponding to the concavo-convex structure of the mold on the surface.

[Example 2] Processed substrate and manufacturing example of a processed substrate using the processed substrate (part 2)
A silicon wafer integrated with a resist film formed by polymerization of the composition 2 is obtained in the same manner as in Example 1 except that the composition 2 is used instead of the composition 1. A concavo-convex structure in which the concavo-convex structure of the mold is transferred with high accuracy is formed on the surface of the resist film. The processed substrate is etched in the same manner as in Example 1 to obtain a silicon wafer having a pattern corresponding to the concavo-convex structure of the mold formed on the surface. The etching resistance of the resist film is almost equal to that of novolak resin.

[Example 3] Processing substrate and processing substrate manufacturing example using the processing substrate (part 3)
A silicon wafer integrated with a resist film formed by polymerization of the composition 3 is obtained in the same manner as in Example 1 except that the composition 3 is used instead of the composition 1. A concavo-convex structure in which the concavo-convex structure of the mold is transferred with high accuracy is formed on the surface of the resist film. Also, the adhesion between the resist film and the silicon wafer is particularly good. The processed substrate is etched in the same manner as in Example 1 to obtain a silicon wafer having a pattern corresponding to the concavo-convex structure of the mold formed on the surface. The etching resistance of the resist film is almost equal to that of novolak resin.

[Example 4] Processed substrate and manufacturing example of a processed substrate using the processed substrate (part 4)
A silicon wafer integrated with a resist film formed by polymerization of the composition 4 is obtained in the same manner as in Example 1 except that the composition 4 is used instead of the composition 1. A concavo-convex structure in which the concavo-convex structure of the mold is transferred with high accuracy is formed on the surface of the resist film. The processed substrate is etched in the same manner as in Example 1 to obtain a silicon wafer having a pattern corresponding to the concavo-convex structure of the mold formed on the surface. The etching resistance of the resist film is slightly inferior to that of novolak resin.

  From the above results, according to the present invention using the resist composition containing the fluorine-containing surfactant and the ring-forming monomer, the substrate and the resist film having a highly accurate desired resist pattern and excellent in etching resistance are integrated. It can be seen that the processed substrate can be easily manufactured. Therefore, highly accurate nanoimprint lithography is realized by the present invention.

A processed substrate obtained by etching a processed substrate obtained by the manufacturing method of the present invention is useful as a semiconductor device. Specific examples of semiconductor devices include memory ICs such as DRAMs and flash memories; logic ICs such as system LSIs; optical semiconductors such as LEDs (light emitting diodes) and LDs (semiconductor lasers); microcomputers, semiconductor sensors, general-purpose linear ICs, Control / driver IC and the like.

Claims (4)

By performing the following step 1, the following step 2, and the following step 3 in order, a processed substrate in which the substrate and the resist film on which the desired resist pattern is formed is obtained is obtained, and then a resist film of the processed substrate is formed. Etching the processed surface and etching the substrate, A method for producing an etched processed substrate.
Step 1: A nonionic fluorine-containing surfactant and a polymerizable monomer having a ring structure, or a polymerizable monomer forming a ring structure by polymerization, by combining a substrate and a mold having a reverse pattern of a desired resist pattern on the surface A step of sandwiching a resist composition comprising: the substrate surface and the pattern surface of the mold.
Step 2: A step of polymerizing a polymerizable monomer in the resist composition to form a resist film from the composition.
Step 3: A step of removing the mold from the resist film to obtain a processed substrate.   The manufacturing method according to claim 1, wherein the reversal pattern of the mold having the reversal pattern on the surface is a fine pattern having convex portions and concave portions, and the average value of the interval between the convex portions is 1 nm to 500 μm.   The method according to claim 1 or 2, wherein the resist composition is a resist composition containing a polymerization initiator.   The production method according to claim 1, wherein the fluorine-containing surfactant is a fluorine-containing surfactant having a fluorine atom content of 10 to 70% by mass.