JP2005275171A - Method for forming pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a pattern, with which a high-resolution graft polymer pattern is easily formed on a solid surface. <P>SOLUTION: In the method for forming the pattern, a step to bond a compound having a photopolymerization initiating site to initiate radical polymerization with photo-cleavage and a substrate bonding site to a substrate, a step to carry out pattern exposure and to deactivate the photopolymerization initiating site on the exposure region, and a step to bring an unsaturated compound capable of radical polymerization into contact with the substrate, and subsequently to generate a graft polymer by exposing an entire surface of the substrate, generating the photo-cleavage on the photopolymerization initiating site remaining on the unexposed region in the pattern exposure and initiating the radical polymerization, are carried out in this order. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to pattern formation, and more particularly to a pattern formation method capable of easily forming a pattern with excellent resolution on a solid surface.

Surface modification with a polymer on a solid surface is widely studied in the industrial field because it can change the properties of the solid surface such as wettability, dirtiness, adhesion, surface friction, and cell affinity. Among them, surface modification with a surface graft polymer obtained by directly bonding a polymer to a solid surface by a covalent bond has the advantage that i) a strong bond is formed between the surface and the graft polymer, ii) grafting It is known that the affinity of a polymer for a substance is greatly different from that of a polymer formed by general coating crosslinking, and a specific property resulting from this difference in affinity can be expressed.
As for the surface graft polymer having the above-mentioned advantages, various applied technologies utilizing its specific properties have been proposed. For example, cell culture, antithrombotic artificial blood vessels, artificial joints and other biological fields, and surface It is used for hydrophilic films that require high hydrophilicity and hydrophilic supports for printing plates.

  In addition, by forming such a surface graft polymer in a pattern, the specific properties of the guft polymer are reflected in the pattern, so it is used in various fields such as printing master plates, compartment culture, and dye image formation. It has been.

  For example, in Non-Patent Document 1, it is possible to form a hydrophilic graft pattern using a polymerization initiating group immobilized on a surface called an iniferter and use it as a cell compartment culture material. It has been reported that a visible image pattern can be formed by adsorbing a dye to a graft pattern (toluidine blue staining).

In Non-Patent Document 3, using an iniferter polymerization initiator immobilized on the surface, a technique for obtaining a graft polymer pattern obtained by polymerizing a hydrophilic or hydrophobic monomer in a pattern, or a monomer having a dye structure is grafted Thus, a technique for obtaining a dye polymer pattern has been reported.
In Non-Patent Document 4, an initiator is attached imagewise on a gold substrate using a microcontact printing method, atom transfer polymerization (ATRP polymerization) is caused from the initiator, HEMA (hydroxyethyl methacrylate) or There has been reported a technique of forming a MMA (methyl methacrylate) graft polymer in a pattern and applying it as a resist.
Further, Non-Patent Document 5 proposes a method for producing a graft pattern by anion radical polymerization from a silane compound immobilized on a substrate or cation radical polymerization.

  However, when trying to produce a graft pattern on a solid surface using the conventional iniferter method or the atom transfer polymerization method as described above, there is a disadvantage that the suitability for production is not sufficient because the reaction time is long. . In addition, when an anion radical polymerization method or a cation radical polymerization method is used, since the polymerization reaction requires strict control, there is a drawback that the production suitability is not sufficient.

As described above, there is a demand for a pattern forming method for obtaining an effective surface-modifying material or a highly functional material by modifying a solid surface with a graft polymer. As for the method that can be easily formed, the present situation has not yet been obtained.
Matsuda et al., "Journal of biomedical materials research", 2000, 53, 584 Matsuda et al., "Langumuir", 1999, Vol. 15, p. 5560 Metters, A, T et al., "Macromolecules", 2003, 36, 6739 CJHawker et al., “Macromolecules”, 2000, 33, 597 Ingall et al., "J.Am.Chem.Soc", 1999, 121, 3607

An object of the present invention is to solve the conventional problems of the present invention and achieve the following objects.
That is, an object of the present invention is to provide a pattern forming method capable of easily forming a high resolution graft polymer pattern on a solid surface.

Means for solving the above-mentioned problems are as follows.
That is, the pattern forming method of the present invention comprises a step of bonding a compound having a photopolymerization initiation site capable of initiating radical polymerization by photocleavage and a substrate binding site to a substrate,
Performing pattern exposure and deactivating the photopolymerization initiation site in the exposed area;
After contacting an unsaturated compound capable of radical polymerization on the substrate, the whole surface is exposed, photocleavage occurs at the photopolymerization start site remaining in the non-exposed area at the time of pattern exposure, and radical polymerization is started. A step of generating a graft polymer by,
Are performed in this order.
In the present invention, the polymerization initiation site is selected from the group consisting of C—C bond, C—N bond, C—O bond, C—Cl bond, N—O bond, and S—N bond. It is preferable to include any of them.

  Although the detailed mechanism in the present invention is not yet clear, since the radical polymerization reaction in the present invention is a polymerization reaction using free radical polymerization, the polymerization rate is high, and the polymerization reaction does not require strict control. It is considered that the graft polymer pattern can be easily formed on the solid surface.

  According to the pattern forming method of the present invention, a high-resolution graft polymer pattern can be easily formed on a solid surface.

Hereinafter, the present invention will be described in detail.
The pattern forming method of the present invention comprises a step of bonding a compound having a photopolymerization initiation site capable of initiating radical polymerization by photocleavage and a base material binding site to a base material (hereinafter referred to as “photocleavable compound binding step” as appropriate). A pattern exposure, a step of deactivating the photopolymerization initiation site in the exposed region (hereinafter, referred to as “a polymerization initiation ability deactivation step” as appropriate), and radical polymerization on the substrate. After exposure to the unsaturated compound, the whole surface is exposed, photo-cleavage occurs in the photo-polymerization initiation site remaining in the non-exposed region at the time of pattern exposure, and radical polymerization is initiated to generate a graft polymer. Steps (hereinafter referred to as “graft polymer generation step” as appropriate) are performed in this order.

First, the outline of the pattern formation method of this invention is demonstrated using FIG. Here, FIG. 1 is a conceptual diagram showing an outline of each step in the pattern forming method of the present invention.
As shown in FIG. 1A, a functional group (represented by Z in the figure) is present on the substrate surface from the beginning. Here, a compound (QY) having a substrate binding site (Q) and a polymerization initiation site (Y) capable of initiating radical polymerization by photocleavage is imparted and brought into contact with the substrate surface. As a result, as shown in FIG. 1B, the functional group (Z) present on the substrate surface and the substrate binding site (Q) are bonded to each other, and the compound (QY) is bonded to the substrate surface. ) Is introduced [photocleavable compound binding step]. Thereafter, pattern exposure is performed on the surface into which the compound (QY) is introduced as indicated by the arrow in FIG. Thereby, the polymerization initiation site (Y) is photo-cleavage by the exposure energy. As a result, as shown in FIG. 1 (c), in the exposed portion of the compound (QY), the polymerization initiation site (Y) is deactivated to become a polymerization initiation ability deactivated site (S) [polymerization. Initiation ability deactivation process].
Thereafter, as shown in FIG. 1 (d), the entire surface is exposed as shown by the arrow in FIG. 1 (d) in a state where a known graft polymer raw material such as a monomer is brought into contact. Thereby, as shown in FIG.1 (e), in the area | region where the polymerization start site | part (Y) remains, a graft polymer produces | generates from the polymerization start site | part (Y) of a compound (QY). [Graft polymer production step].

Hereinafter, such a pattern forming method will be specifically described.
The group represented by Z in FIG. 1 is a functional group present on the surface of the substrate, and specific examples include a hydroxyl group, a carboxyl group, and an amino group. These functional groups may be originally present on the surface of the base material due to the material of the base material in the silicon substrate or glass substrate, and may be present on the surface by subjecting the base material surface to a surface treatment such as corona treatment. It may be.

Next, the structure of a compound having a polymerization initiation site capable of initiating radical polymerization by photocleavage (hereinafter simply referred to as polymerization initiation site) and a substrate binding site will be specifically described. If this compound is described in detail using a model of a compound (QY) having a base material binding site (Q) and a polymerization initiation site (Y) in the conceptual diagram of FIG. The initiation site (Y) is a structure containing a single bond that can be cleaved by light.
As the single bond that is cleaved by this light, carbonyl α-cleavage, β-cleavage reaction, light-free rearrangement reaction, phenacyl ester cleavage reaction, sulfonimide cleavage reaction, sulfonyl ester cleavage reaction, N-hydroxysulfonyl ester cleavage reaction, benzyl Examples thereof include a single bond that can be cleaved by using an imide cleavage reaction, a cleavage reaction of an active halogen compound, or the like. These reactions break a single bond that can be cleaved by light. Examples of the single bond that can be cleaved include a C—C bond, a C—N bond, a C—O bond, a C—Cl bond, a N—O bond, and a S—N bond.

  In addition, since the polymerization initiation site (Y) containing a single bond that can be cleaved by light is the starting point of graft polymerization in the graft polymer production step, when the single bond that can be cleaved by light is cleaved, the cleavage reaction causes Has the function of generating radicals. Thus, the structure of the polymerization initiation site (Y) having a single bond that can be cleaved by light and capable of generating radicals includes an aromatic ketone group, a phenacyl ester group, a sulfonimide group, and a sulfonyl ester group. , N-hydroxysulfonyl ester groups, benzylimide groups, trichloromethyl groups, benzyl chloride groups, and other structures.

Since such a polymerization initiation site (Y) is cleaved by exposure to generate a radical, if there is a polymerizable compound in the vicinity of the radical, this radical functions as a starting point for the graft polymerization reaction. The graft polymer can be produced (graft polymer production region).
On the other hand, even if the polymerization initiation site (Y) is cleaved by exposure and a radical is generated, if there is no polymerizable compound in the vicinity of the radical, the radical is deactivated without being used. The polymerization initiating ability itself is deactivated. As a result, such a region becomes a non-grafted polymer region.

  On the other hand, the base material binding site (Q) is composed of a reactive group capable of reacting with and binding to the functional group (Z) present on the base material surface. And groups as shown below.

  The polymerization initiation site (Y) and the substrate binding site (Q) may be directly bonded or may be bonded via a linking group. Examples of the linking group include a linking group containing an atom selected from the group consisting of carbon, nitrogen, oxygen, and sulfur. Specifically, for example, a saturated carbon group, an aromatic group, an ester group, an amide group. Ureido group, ether group, amino group, sulfonamide group and the like. This linking group may further have a substituent, and examples of the substituent that can be introduced include an alkyl group, an alkoxy group, and a halogen atom.

  Specific examples [Exemplary Compound 1 to Exemplified Compound 16] of Compound (QY) having a substrate binding site (Q) and a polymerization initiation site (Y) are shown below together with the cleavage portion. However, it is not limited to these.

The photocleavable compound bonding step in the present invention is a step of bonding such a compound (QY) to a substrate.
As a method for bonding the compound (QY) as exemplified to the functional group Z present on the substrate surface, the compound (QY) is dissolved or dispersed in a suitable solvent such as toluene, hexane, acetone or the like. A method of applying the solution or dispersion to the surface of the substrate or a method of immersing the substrate in the solution or dispersion may be applied. At this time, the concentration of the compound (QY) in the solution or in the dispersion is preferably 0.01% by mass to 30% by mass, and particularly preferably 0.1% by mass to 15% by mass. As a liquid temperature in the case of making it contact, 0 to 100 degreeC is preferable. The contact time is preferably 1 second to 50 hours, and more preferably 10 seconds to 10 hours.

There is no restriction | limiting in particular in the base material used in this invention, The base material which has functional groups (Z), such as a hydroxyl group, a carboxyl group, and an amino group, or a corona treatment, a glow process, a plasma treatment, etc. By this surface treatment, a substrate in which a hydroxyl group, a carboxyl group or the like is generated can be applied.
In general, a flat substrate is used, but the substrate is not necessarily limited to a flat substrate, and the graft polymer may be similarly introduced to the surface of a substrate having an arbitrary shape such as a cylindrical shape. it can.

Specific examples of the base material suitable for the present invention include various base materials having surface hydroxyl groups such as glass, quartz, ITO, and silicon, and surface treatment such as corona treatment, glow treatment, plasma treatment, and the like. Examples thereof include plastic base materials such as PET, polypropylene, polyimide, epoxy, acrylic, and urethane in which groups are generated.
The thickness of the substrate is selected according to the purpose of use and is not particularly limited, but is generally about 10 μm to 10 cm.

  Then, in the polymerization initiating ability deactivation step, pattern exposure is performed along the region where the graft polymer is not desired to be generated, and the compound (QY) bonded to the substrate surface is photocleavaged to lose the polymerization initiating ability. Make it live.

In this way, after the polymerization startable region and the polymerization initiating ability deactivation region are formed, a graft polymer generation step is performed.
In this graft polymer formation step, a radically polymerizable unsaturated compound (for example, a hydrophilic monomer) is used as a material for the desired graft polymer, using a substrate having a polymerization startable region and a polymerization initiating ability deactivated region. Then, the entire surface is exposed to activate the polymerization initiating group in the polymerization startable region to generate a radical, and the graft reaction between the radical and the unsaturated compound capable of radical polymerization is started. Occur and progress. As a result, a graft polymer is formed only in the region where polymerization can be initiated.

  In addition, as a method of bringing the unsaturated compound capable of radical polymerization into contact with the substrate surface, a method of applying a solution or a dispersed dispersion in which the unsaturated compound capable of radical polymerization is dissolved, the substrate in the solution or the dispersion liquid There is a method of soaking.

As the unsaturated compound capable of radical polymerization used in the graft polymer production step, any compound having a radical polymerizable group can be used. For example, hydrophilic monomers, hydrophobic monomers, macromers, oligomers can be used. And polymers having a polymerizable unsaturated group. In the present invention, hydrophilic polymers, hydrophilic macromers, hydrophilic monomers and the like having a hydrophilic group which is a polar group are preferred.
Specific examples of the unsaturated compound capable of radical polymerization that are preferably used in the graft polymer production step are shown below.

-Hydrophilic polymer having a polymerizable unsaturated group-
The hydrophilic polymer having a polymerizable unsaturated group is a radically polymerizable group-containing hydrophilic polymer in which an ethylene addition polymerizable unsaturated group such as a vinyl group, an allyl group or a (meth) acryl group is introduced in the molecule. Point to. This radical polymerizable group-containing hydrophilic polymer needs to have a polymerizable group at the main chain end and / or side chain, and preferably has a polymerizable group at both of them. Hereinafter, a hydrophilic polymer having a polymerizable group (at the main chain end and / or side chain) is referred to as a radical polymerizable group-containing hydrophilic polymer.

Such a radically polymerizable group-containing hydrophilic polymer can be synthesized as follows.
As a synthesis method, (a) a method of copolymerizing a hydrophilic monomer and a monomer having an ethylene addition polymerizable unsaturated group, (b) copolymerizing a hydrophilic monomer and a monomer having a double bond precursor, Next, a method of introducing a double bond by treatment with a base or the like, and (c) a method of reacting a functional group of a hydrophilic polymer with a monomer having an ethylene addition polymerizable unsaturated group. Among these, from the viewpoint of synthesis suitability, (c) a method of reacting a functional group of a hydrophilic polymer with a monomer having an ethylene addition polymerizable unsaturated group is particularly preferable.

In the methods (a) and (b), the hydrophilic monomer used for the synthesis of the radical polymerizable group-containing hydrophilic polymer includes (meth) acrylic acid or its alkali metal salt and amine salt, itaconic acid or its alkali. Metal salt and amine salt, 2-hydroxyethyl (meth) acrylate, (meth) acrylamide, N-monomethylol (meth) acrylamide, N-dimethylol (meth) acrylamide, allylamine or its hydrohalide, 3-vinylpropion Acid or alkali metal salt and amine salt thereof, vinyl sulfonic acid or alkali metal salt and amine salt thereof, 2-sulfoethyl (meth) acrylate, polyoxyethylene glycol mono (meth) acrylate, 2-acrylamido-2-methylpropanesulfone Monomers having hydrophilic groups such as carboxyl groups, sulfonic acid groups, phosphoric acid groups, amino groups or salts thereof, hydroxyl groups, amide groups and ether groups, such as acid phosphooxypolyoxyethylene glycol mono (meth) acrylate Can be mentioned.
As the hydrophilic polymer used in the method (c), a hydrophilic homopolymer or copolymer obtained using at least one selected from these hydrophilic monomers is used.

  When the radically polymerizable group-containing hydrophilic polymer is synthesized by the method (a), examples of the monomer having an ethylene addition polymerizable unsaturated group that is copolymerized with the hydrophilic monomer include an allyl group-containing monomer. Examples include allyl (meth) acrylate and 2-allyloxyethyl methacrylate.

  Further, when the radical polymerizable group-containing hydrophilic polymer is synthesized by the method (b), a monomer having a double bond precursor that is copolymerized with a hydrophilic monomer is 2- (3-chloro-1-oxopropoxy). ) Ethyl methacrylate.

  Further, when the radical polymerizable group-containing hydrophilic polymer is synthesized by the method (c), a reaction between a carboxyl group, an amino group or a salt thereof in the hydrophilic polymer and a functional group such as a hydroxyl group and an epoxy group is performed. It is preferable to introduce an unsaturated group using it. Examples of the monomer having an addition polymerizable unsaturated group used for this purpose include (meth) acrylic acid, glycidyl (meth) acrylate, allyl glycidyl ether, and 2-isocyanatoethyl (meth) acrylate.

-Hydrophilic macromonomer-
The method for producing a macromonomer that can be used in the present invention is described in, for example, Chapter 2 of “Macromonomer Chemistry and Industry” (Editor, Yuya Yamashita) published on September 20, 1999 by the IP Publishing Bureau. Various production methods have been proposed in “Synthesis”.
Particularly useful hydrophilic macromonomers that can be used in the present invention include macromonomers derived from carboxyl group-containing monomers such as acrylic acid and methacrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, and vinylsterene sulfone. Sulfonic acid macromonomer derived from monomer of acid and its salt, (meth) acrylamide, N-vinylacetamide, N-vinylformamide, amide macromonomer derived from N-vinylcarboxylic amide monomer, hydroxyethyl Macromonomers derived from hydroxyl group-containing monomers such as methacrylic acid, hydroxyethyl acrylate, glycerol monomethacrylate, methoxyethyl acrylate, methoxypolyethylene glycol acrylate, polyethylene glycol Macromonomers derived from alkoxy group or ethylene oxide group-containing monomers such Lumpur acrylate. A monomer having a polyethylene glycol chain or a polypropylene glycol chain can also be usefully used as the macromonomer of the present invention.
Among these hydrophilic macromonomers, useful ones have a molecular weight in the range of 250 to 100,000, and a particularly preferable range is 400 to 30,000.

-Hydrophilic monomer-
The hydrophilic monomer may be a monomer having a positive charge such as ammonium or phosphonium, or an acid having a negative charge such as a sulfonic acid group, a carboxyl group, a phosphoric acid group, or a phosphonic acid group or capable of dissociating into a negative charge. Examples thereof include monomers having a group, but other hydrophilic monomers having a nonionic group such as a hydroxyl group, an amide group, a sulfonamide group, an alkoxy group, and a cyano group can also be used.

Specific examples of the hydrophilic monomer that can be used in the present invention include the following monomers.
For example, (meth) acrylic acid or its alkali metal salt and amine salt, itaconic acid or its alkali metal salt and amine salt, allylamine or its hydrohalide salt, 3-vinylpropionic acid or its alkali metal salt and amine salt, Vinyl sulfonic acid or its alkali metal salt and amine salt, styrene sulfonic acid or its alkali metal salt and amine salt, 2-sulfoethylene (meth) acrylate, 3-sulfopropylene (meth) acrylate or its alkali metal salt and amine salt, 2-acrylamido-2-methylpropanesulfonic acid or alkali metal salts and amine salts thereof, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate or salts thereof, 2-dimethylaminoethyl (meta Acrylate or its hydrohalide, 3-trimethylammoniumpropyl (meth) acrylate, 3-trimethylammoniumpropyl (meth) acrylamide, N, N, N-trimethyl-N- (2-hydroxy-3-methacryloyloxypropyl) Ammonium chloride and the like can be used. In addition, 2-hydroxyethyl (meth) acrylate, (meth) acrylamide, N-monomethylol (meth) acrylamide, N-dimethylol (meth) acrylamide, N-vinylpyrrolidone, N-vinylacetamide, polyoxyethylene glycol mono (meth) ) Acrylate is also useful.

-Solvent-
The solvent for dissolving and dispersing the above-mentioned radically polymerizable unsaturated compound is not particularly limited as long as the compound and additives added as necessary can be dissolved.
For example, when a hydrophilic compound such as a hydrophilic monomer is applied, an aqueous solvent such as water or a water-soluble solvent is preferable, and a mixture thereof or a solvent in which a surfactant is further added is preferable. . The water-soluble solvent refers to a solvent miscible with water in an arbitrary ratio, and examples of such a water-soluble solvent include alcohol solvents such as methanol, ethanol, propanol, ethylene glycol, and glycerin, acids such as acetic acid, Examples include ketone solvents such as acetone and amide solvents such as formamide.
When hydrophobic compounds such as hydrophobic monomers are applied, alcohol solvents such as methanol, ethanol, 1-methoxy-2-propanol, ketone solvents such as methyl ethyl ketone, and aromatics such as toluene. A group hydrocarbon solvent is preferred.

There is no particular limitation on the exposure method that can be used for the pattern exposure in the polymerization inactivation ability deactivation step of the pattern formation method of the present invention and the overall exposure in the graft polymer generation step, and the energy that causes cleavage at the polymerization start site (Y). As long as exposure is possible, exposure with ultraviolet rays or exposure with visible light may be used. Moreover, the pattern exposure in the polymerization initiating ability deactivation step and the entire surface exposure in the graft polymer generation step may be performed under the same exposure conditions or different exposure conditions.
Examples of the light source used for exposure include ultraviolet light, deep ultraviolet light, visible light, and laser light. Specifically, excimer lasers such as ultraviolet light, i-line, g-line, KrF, and ArF are used. Among these, i-line, g-line, and excimer laser are preferable.

The resolution of the pattern formed by the present invention depends on the exposure conditions.
By using the pattern forming method of the present invention, a high-resolution pattern can be formed, and a high-definition pattern corresponding to the exposure can be formed by performing high-definition pattern exposure. Examples of the exposure method for forming a high-definition pattern include light beam scanning exposure using an optical system, exposure using a mask, and the like, and an exposure method corresponding to the resolution of a desired pattern may be taken.
Specific examples of the high-definition pattern exposure include stepper exposure such as i-line stepper, g-line stepper, KrF stepper, and ArF stepper.

  Thus, by the pattern formation method of the present invention, the substrate on which the pattern composed of the graft polymer generation region and the non-generation region is formed on the surface is subjected to a treatment such as solvent immersion or solvent washing after exposure, The remaining homopolymer is removed and purified. Specifically, washing with water or acetone, drying and the like can be mentioned. From the viewpoint of homopolymer removability, it is preferable to adopt means such as ultrasonic waves. The purified base material has the homopolymer remaining on the surface completely removed, and only the patterned graft polymer firmly bonded to the base material is present.

  For these reasons, according to the pattern forming method of the present invention, a fine pattern corresponding to the exposure resolution can be easily formed, so that the application range is wide.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.
(Synthesis Example 1: Synthesis of Compound A)
The exemplary compound 1 is synthesized by the following two steps. A description will be given of the scheme of each step.

1. Step 1 (Synthesis of Compound a)
24.5 g (0.12 mol) of 1-hydroxycyclohexyl phenyl ketone was dissolved in a mixed solvent of DMAc 50 g and THF 50 g, and 7.2 g (0.18 mol) of NaH (60% in oil) was gradually added in an ice bath. Thereto, 44.2 g (0.18 mol) of 11-bromo-1-undecene (95%) was added dropwise and reacted at room temperature. The reaction was completed in 1 hour. The reaction solution was poured into ice water and extracted with ethyl acetate to obtain a mixture containing Compound a in the form of a yellow solution. 37 g of this mixture was dissolved in 370 ml of acetonitrile, and 7.4 g of water was added. 1.85 g of p-toluenesulfonic acid monohydrate was added and stirred at room temperature for 20 minutes. The organic phase was extracted with ethyl acetate and the solvent was distilled off. Compound a was isolated by column chromatography (filler: Wakogel C-200, developing solvent: ethyl acetate / hexane = 1/80).
A synthesis scheme is shown below.

¹ H NMR (300 MHz CDCl ₃ )
δ = 1.2-1.8 (mb, 24H), 2.0 (q, 2H), 3.2 (t, J = 6.6, 2H), 4.9-5.0 (m, 2H) ) 5.8 (ddt, J = 24.4, J = 10.5, J = 6.6, 1H _. ), 7.4 (t, J = 7.4, 2H), 7.5 (t, J = 7.4, 1H), 8.3 (d, 1H)

2. Step 2 (Synthesis of Compound A by Hydrosilylation of Compound a)
Compound 5.0 g of (0.014 mol) in _{Speir catalyst (H 2 PtCl 6 ·} 6H 2 O / 2-PrOH, 0.1mol / l) and 2 drops of an ice bath trichlorosilane 2.8 g (0.021 mol ) Was added dropwise and stirred. After 1 hour, 1.6 g (0.012 mol) of trichlorosilane was added dropwise, and the temperature was returned to room temperature. The reaction was complete after 3 hours. After completion of the reaction, unreacted trichlorosilane was distilled off under reduced pressure to obtain Compound A.
A synthesis scheme is shown below.

¹ H NMR (300 MHz CDCl ₃ )
δ = 1.2−1.8 (m, 30H), 3.2 (t, J = 6.3, 2H), 7.3-7.7 (m, 3H), 8.3 (d, 2H) )

(Synthesis Example 2: Synthesis of hydrophilic polymer P having a polymerizable group)
18 g of polyacrylic acid (average molecular weight 25,000) is dissolved in 300 g of DMAc (dimethylacetamide), and 0.41 g of hydroquinone, 19.4 g of 2-methacryloyloxyethyl isocyanate and 0.25 g of dibutyltin dilaurate are added thereto. , Reacted at 65 ° C. for 4 hours. The acid value of the obtained polymer was 7.02 meq / g. The carboxyl group was neutralized with a 1 mol / l sodium hydroxide aqueous solution, the polymer was precipitated in addition to ethyl acetate, and washed well to obtain a hydrophilic polymer P having a polymerizable group.

[Example 1]
(Photocleavable compound binding step)
A glass substrate (manufactured by Nippon Sheet Glass Co., Ltd.) was immersed in a piranha solution (sulfuric acid / 30% hydrogen peroxide = 1/1 vol mixed solution) overnight and then washed with pure water. The substrate was placed in a separable flask purged with nitrogen and immersed in a dehydrated toluene solution of 12.5% by mass of Compound A for 1 hour. After taking out, it wash | cleaned in order with toluene, acetone, and a pure water. The substrate to which compound A thus obtained is bonded is referred to as substrate A1.

(Polymerization initiation ability deactivation process)
A pattern mask (NC-1, manufactured by Toppan Printing Co., Ltd.) was clipped to one side of the substrate A1, and pattern exposure was performed for 1 minute with an exposure machine (UVX-02516S1LP01, manufactured by USHIO INC.). The substrate thus treated is referred to as a substrate B1.

(Graft polymer production process)
Hydrophilic polymer P (0.5 g) was dissolved in a mixed solvent of 4.0 g of pure water and 2.0 g of acetonitrile to prepare a coating solution for producing a graft polymer. The graft forming layer coating solution was applied to the pattern exposure surface of the substrate B1 by a spin coater. The spin coater was first rotated at 300 rpm for 5 seconds and then at 1000 rpm for 20 seconds. The coated substrate B1 was dried at 100 ° C. for 2 minutes. The thickness of the graft polymer production layer after drying was 2 μm.
The entire surface of the substrate having the graft polymer generation layer was exposed with an exposure machine (UVX-02516S1LP01, manufactured by USHIO INC.) For 5 minutes. Thereafter, the exposed surface was sufficiently washed with pure water.
As described above, a pattern C1 was formed.

[Example 2]
(Photocleavable compound binding step)
A single-side corona-treated PET (biaxially stretched polyethylene terephthalate film) having a thickness of 188 μm is cut into a size of 5 cm × 5 cm, and the substrate is placed in a separable flask purged with nitrogen to contain 12.5% by mass of Compound A. It was immersed in a dehydrated toluene solution for 1 hour. After taking out, it wash | cleaned in order with toluene, acetone, and a pure water. The substrate to which compound A thus obtained is bonded is referred to as substrate A2.

(Polymerization initiation ability deactivation process)
Pattern exposure was performed on the surface of Compound A2 on which Compound A was bonded in the same manner as in Example 1. The substrate thus treated is referred to as substrate B2.

(Graft polymer production process)
Acrylic acid aqueous solution is placed between the PET substrate (substrate A2) and the quartz plate by suspending it in 1.0 ml of a 20% by mass aqueous solution of acrylic acid on the pattern exposure surface of the substrate B2, and placing quartz glass thereon. Was sandwiched.
Thereafter, the entire surface exposure was performed in the same manner as in Example 1. Thereafter, the exposed surface was sufficiently washed with pure water.
As described above, the pattern C2 was formed.

<Confirmation and evaluation of pattern>
About pattern C1 and C2 obtained by Example 1 and 2, the pattern was confirmed with the following confirmation method (1) and (2).

[Confirmation method (1)]
The patterns C1 and C2 were observed with an atomic microscope AFM (Nanopics 1000, manufactured by Seiko Instruments Inc., using a DFM cantilever). Table 1 shows the minimum line-and-space line width that could be resolved.
[Confirmation method (2)]
The substrate having the patterns C1 and C2 was immersed in a 0.1% by mass methylene blue aqueous solution for 5 minutes and washed with pure water. Then, each pattern was confirmed with the optical microscope. Table 1 shows the minimum line-and-space line width that could be resolved.

  As shown in Table 1, in Examples 1 and 2 in which pattern formation was performed by the pattern formation method of the present invention, a fine graft polymer pattern having a line and space of 10 μm or less was easily formed in both cases. confirmed.

It is a conceptual diagram which shows the outline of each process in the pattern formation method of this invention.

Claims (2)

Binding a compound having a photopolymerization initiation site capable of initiating radical polymerization by photocleavage and a substrate binding site to the substrate;
Performing pattern exposure and deactivating the photopolymerization initiation site in the exposed area;
After contacting an unsaturated compound capable of radical polymerization on the substrate, the whole surface is exposed, photocleavage occurs at the photopolymerization start site remaining in the non-exposed area at the time of pattern exposure, and radical polymerization is started. A step of generating a graft polymer by,
Are formed in this order.   The polymerization initiation site includes any one selected from the group consisting of C—C bond, C—N bond, C—O bond, C—Cl bond, N—O bond, and S—N bond. The pattern forming method according to claim 1.

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