JP7395278B2 - Photosensitive composition, device, and device manufacturing method - Google Patents

Description

The present invention relates to a photosensitive composition, a device, and a method for manufacturing the device.

Conventionally, photolithography technology is known as a technology for forming a pattern on a photosensitive film formed from a photosensitive composition. In photolithography technology, a pattern can be formed on a photosensitive film by exposing the photosensitive film to light in a pattern and then developing the photosensitive film. In this specification, a developed photosensitive film may be referred to as a "developed film".

Photolithography technology is also used to fabricate devices such as biochips and microchannel chips. For example, Patent Document 1 discloses a photosensitive composition for producing a biochip using photolithography technology.

JP 2018-102159 Publication

Depending on the field in which the device is used, the developed film is required to have high water repellency. Furthermore, a photosensitive composition for forming a developed film is required to have good developability.

Therefore, an object of the present invention is to provide a novel photosensitive composition that can form a developed film having high water repellency and has good developability.

［式（１）中、Ｒ_ff ¹～Ｒ_ff ⁴は各々独立に、フッ素原子、炭素数１～７のパーフルオロアルキル基、又は炭素数１～７のパーフルオロアルキルエーテル基を表す。Ｒ_ff ¹及びＲ_ff ²は、連結して環を形成してもよい。］ The present invention
A polymer containing a structural unit represented by the following formula (1),
At least one selected from the group consisting of a photoacid generator and a photobase generator,
Provided is a photosensitive composition comprising:

[In formula (1), R _ff ¹ to R _ff ⁴ each independently represent a fluorine atom, a perfluoroalkyl group having 1 to 7 carbon atoms, or a perfluoroalkyl ether group having 1 to 7 carbon atoms. R _ff ¹ and R _ff ² may be connected to form a ring. ]

［式（１）中、Ｒ_ff ¹～Ｒ_ff ⁴は各々独立に、フッ素原子、炭素数１～７のパーフルオロアルキル基、又は炭素数１～７のパーフルオロアルキルエーテル基を表す。Ｒ_ff ¹及びＲ_ff ²は、連結して環を形成してもよい。］ Furthermore, the present invention
A substrate and
a water-repellent film disposed on the substrate and having an opening;
A device is provided in which the water-repellent film has a polymer containing a structural unit represented by the following formula (1).

[In formula (1), R _ff ¹ to R _ff ⁴ each independently represent a fluorine atom, a perfluoroalkyl group having 1 to 7 carbon atoms, or a perfluoroalkyl ether group having 1 to 7 carbon atoms. R _ff ¹ and R _ff ² may be connected to form a ring. ]

According to the present invention, a novel photosensitive composition that can form a developed film having high water repellency and has good developability can be provided.

FIG. 1 is a cross-sectional view showing an example of a device. FIG. 3 is a diagram showing a state in which a photosensitive film is placed on a substrate. FIG. 2B is a diagram showing a state in which a part of the photosensitive film in FIG. 2A is exposed.

Embodiments of the present invention will be described below, but the following description is not intended to limit the present invention to specific embodiments.

[Photosensitive composition]
The photosensitive composition of the present embodiment comprises a polymer (P) containing a structural unit (A) represented by the following formula (1), and at least one member selected from the group consisting of a photoacid generator and a photobase generator. including.

In formula (1), R _ff ¹ to R _ff ⁴ each independently represent a fluorine atom, a perfluoroalkyl group having 1 to 7 carbon atoms, or a perfluoroalkyl ether group having 1 to 7 carbon atoms. R _ff ¹ and R _ff ² may be connected to form a ring. "Perfluoro" means that all hydrogen atoms bonded to carbon atoms are replaced with fluorine atoms. In formula (1), the number of carbon atoms in the perfluoroalkyl group is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1. The perfluoroalkyl group may be linear or branched. Examples of the perfluoroalkyl group include a trifluoromethyl group, a pentafluoroethyl group, and a heptafluoropropyl group.

In formula (1), the number of carbon atoms in the perfluoroalkyl ether group is preferably 1 to 5, more preferably 1 to 3. The perfluoroalkyl ether group may be linear or branched. Examples of the perfluoroalkyl ether group include perfluoromethoxymethyl group.

When R _ff ¹ and R _ff ² are linked to form a ring, the ring may be a 5-membered ring or a 6-membered ring. Examples of this ring include a perfluorotetrahydrofuran ring, a perfluorocyclopentane ring, and a perfluorocyclohexane ring.

Specific examples of the structural unit (A) include structural units represented by the following formulas (A1) to (A8).

Among the structural units represented by the above formulas (A1) to (A8), the structural unit (A) is preferably the structural unit (A2), that is, the structural unit represented by the following formula (2).

The structural unit (A) is derived from, for example, a compound represented by the following formula (3). In formula (3), R _ff ¹ to R _ff ⁴ are the same as in formula (1).

Specific examples of the compound represented by the above formula (3) include compounds represented by the following formulas (M1) to (M8).

The polymer (P) may contain one or more structural units (A). The polymer (P) contains, for example, the structural unit (A) as a main component. As used herein, the term "main component" refers to the constituent unit contained in the polymer (P) in the largest amount on a molar basis. The content of the structural unit (A) in the polymer (P) is, for example, 80 mol% or more, preferably 90 mol% or more, and more preferably 95 mol% or more. The polymer (P), for example, essentially consists of the structural unit (A).

The polymer (P) may further contain a structural unit (B) other than the structural unit (A). Examples of the compound forming the other structural unit (B) include fluorine-containing olefin compounds such as tetrafluoroethylene and chlorotrifluoroethylene; perfluorovinyl ether compounds such as perfluoropropyl vinyl ether; perfluoroallyl vinyl ether, perfluorobutyl vinyl ether, etc. Examples include fluorine-containing compounds having two or more polymerizable double bonds and capable of cyclization polymerization, such as tenyl vinyl ether.

The polymer (P) preferably contains substantially no hydrogen atoms, and is more preferably perfluorinated from the viewpoint of improving the water repellency of the developed film formed from the photosensitive composition. "The polymer is perfluorinated" means that in the polymer, all hydrogen atoms bonded to carbon atoms are replaced with fluorine atoms. As far as the present inventors are aware, there is no example of utilizing a perfluorinated polymer in a photosensitive composition.

The polymerization method for the polymer (P) is not particularly limited, and for example, general polymerization methods such as radical polymerization can be used. The polymerization initiator for polymerizing the polymer (P) may be a perfluorinated compound.

The weight average molecular weight of the polymer (P) is, for example, 5,000 to 1,000,000. The glass transition temperature (Tg) of the polymer (P) is, for example, 100°C to 150°C. In this specification, Tg means the midpoint glass transition temperature (T _mg ) determined in accordance with the provisions of JIS K7121:1987.

The content of the polymer (P) in the photosensitive composition is, for example, 1 wt% or more, preferably 5 wt% or more. The content of the polymer (P) may be 99.9 wt% or less, or 80 wt% or less.

The photosensitive composition of the present embodiment preferably contains one of a photoacid generator and a photobase generator, and preferably contains a photoacid generator. The photoacid generator is not particularly limited as long as it is a compound that generates an acid when irradiated with light of a specific wavelength, and examples thereof include triarylsulfonium salts, diaryliodonium salts, and sulfonyldiazomethane.

Examples of cations contained in triarylsulfonium salts include triphenylsulfonium, diphenyl-4-methylphenylsulfonium, tris(4-methylphenyl)sulfonium, diphenyl-2,4,6-trimethylphenylsulfonium, and 4-(phenylthio). ) phenyldiphenylsulfonium. Anions contained in triarylsulfonium salts include trifluoromethanesulfonate, nonafluorobutanesulfonate, hexafluorophosphate, tetrafluoroborate, tris(pentafluoroethyl)trifluorophosphate, tris(heptafluoropropyl)trifluorophosphate, tris( nonafluoroisobutyl) trifluorophosphate and bis(nonafluoroisobutyl)tetrafluorophosphate.

Examples of cations contained in diaryliodonium salts include diphenyliodonium, 4-isopropyl-4'-methyldiphenyliodonium, 4-methyl-4'-methylpropyldiphenyliodonium, bis(4-tert-butylphenyl)iodonium, and 4-tert-butylphenyl)iodonium. -methoxyphenylphenyliodonium. Examples of the anion contained in the diaryliodonium salt include those mentioned above for the triarylsulfonium salt.

Examples of the sulfonyldiazomethane include bis(phenylsulfonyl)diazomethane, bis(tert-butylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, and bis(p-toluenesulfonyl)diazomethane.

The photoacid generator is preferably tris(4-methylphenyl)sulfonium nonafluorobutanesulfonate, 4-(phenylthio)phenyldiphenylsulfonium tris(heptafluoropropyl)trifluorophosphate, 4-(phenylthio)phenyldiphenylsulfonium tris( nonafluoroisobutyl) trifluorophosphate, 4-(phenylthio)phenyldiphenylsulfonium bis(nonafluoroisobutyl)tetrafluorophosphate, 4-(phenylthio)phenyldiphenylsulfonium (pentafluoroethyl) trifluorophosphate, diphenyl-2,4,6 -trimethylphenylsulfonium trifluoromethanesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium nonafluorobutanesulfonate, bis(phenylsulfonyl)diazomethane or bis(p-toluenesulfonyl)diazomethane. The photoacid generators were IRGACURE (registered trademark) 250 manufactured by BASF; CPI (registered trademark) -100P and CPI (registered trademark) -210S manufactured by Sun-Apro; WPAG-638 and WPAG manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. -199 etc. may be used. The photosensitive composition of this embodiment may contain one or more photoacid generators.

The photobase generator is not particularly limited as long as it is a compound that generates a base when irradiated with light of a specific wavelength. Examples of the photobase generator include 1-(anthraquinon-2-yl)ethyl N-cyclohexylcarbamate, 9-anthrylmethyl N,N-diethylcarbamate, 9-anthrylmethyl piperidine-1-carboxylate, 9-anthrylmethyl N,N-dicyclohexylcarbamate, 1-(anthraquinon-2-yl)ethyl N,N-dicyclohexylcarbamate, 1-(anthraquinon-2-yl)ethyl imidazole-1-carboxylate, cyclohexylammonium 2-(3-benzoylphenyl)propionate, (E)-N-cyclohexyl-3-(2-hydroxyphenyl)acrylamide, dicyclohexylammonium 2-(3-benzoylphenyl)propionate, 1,2-dicyclohexyl- 4,4,5,5-tetramethylbiguanidium=n-butyltriphenylborate, 1,2-diisopropyl-3-[bis(dimethylamino)methylene]guanidinium=2-(3-benzoylphenyl)propionate, (2-nitrophenyl)methyl 4-hydroxypiperidine-1-carboxylate, (2-nitrophenyl)methyl 4-(methacryloyloxy)piperidine-1-carboxylate, guanidium 2-(3-benzoylphenyl)propionate, and (E)-1-piperidino-3-(2-hydroxyphenyl)-2-propen-1-one is mentioned. As the photobase generator, WPBG series manufactured by Fuji Film Wako Pure Chemical Industries, Ltd. can be used. The photosensitive composition of this embodiment may contain one or more photobase generators.

The content of the photoacid generator in the photosensitive composition is, for example, 0.1 wt% to 10 wt%, preferably 1 wt% to 5 wt%. The content of the photobase generator in the photosensitive composition is, for example, 0.1 wt% to 10 wt%, preferably 1 wt% to 5 wt%.

The photosensitive composition of the present embodiment may or may not further contain components other than the polymer (P), the photoacid generator, and the photobase generator. Other components include polymers other than polymer (P), solvents, photosensitizers, antioxidants, adhesion promoters, leveling agents, antifoaming agents, suspending agents, dispersants, plasticizers, and thickeners. Examples include agents.

The solvent contained in the photosensitive composition is preferably one that dissolves or disperses the polymer (P), the photoacid generator, and the photobase generator, for example. Examples of the solvent include 1H-tridecafluorohexane (manufactured by Asahi Glass Co., Ltd., Asahiklin (registered trademark) AC2000), 1,1,1,2,2,3,3,4,4,5,5,6, 6-tridecafluorooctane (manufactured by Asahi Glass Co., Ltd., Asahiklin (registered trademark) AC6000), 1,1,2,2-tetrafluoro-1-(2,2,2-trifluoroethoxy)ethane (manufactured by Asahi Glass Co., Ltd.) Asahiklin (registered trademark) AE3000), dichloropentafluoropropane (manufactured by Asahi Glass Co., Ltd., Asahiklin (registered trademark) AK-225), 1,1,1,2,3,4,4,5,5,5-deca Fluoro-3-methoxy-2-(trifluoromethyl)pentane (manufactured by Asahi Glass Co., Ltd., Cytop (registered trademark) CT-solv100E), 1-methoxynonafluorobutane (manufactured by 3M Japan, Novec (registered trademark) 7100), 1-Ethoxynonafluorobutane (manufactured by 3M Japan Ltd., Novec (registered trademark) 7200), perfluorohexyl methyl ether (manufactured by 3M Japan Ltd., Novec (registered trademark) 7300), 1,1,1,2,3,3 -hexafluoro-4-(1,1,2,3,3,3-hexafluoropropoxy)pentane (manufactured by 3M Japan, Novec (registered trademark) 7600), 2H,3H-perfluoropentane (Mitsui Chemours) Vertrel (registered trademark) XF), 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanol, 4,4 , 5,5,6,6,7,7,8,8,9,9,9-tridecafluoro-1-nonanol, hexafluorobenzene, hexafluoro-2-propanol, 2,2,3,3, Fluorine-containing compounds such as 4,4,5,5-octafluoro-1-pentanol, 1H,1H,7H-dodecafluoro-1-heptanol, and commercially available fluorine-based solvents other than these (for example, 3M Japan Fluorinert (registered trademark) FC-770 manufactured by Co., Ltd., and Serefin (registered trademark) 1233Z manufactured by Central Glass Co., Ltd.); non-fluorine ketones such as cyclopentanone, cyclohexanone, methyl amyl ketone, and 2-butanone; ethyl lactate; Esters such as methyl benzoate, ethyl benzoate, benzyl benzoate, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol methyl ethyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene carbonate; diethylene glycol methyl Examples include ethers such as ethyl ether, tetrahydrofuran, dioxane, dimethoxyethane, diethoxyethane, anisole, diglyme, and triglyme. The photosensitive composition may contain one or more of these solvents. From the viewpoint of the solubility of the components contained in the photosensitive composition and the film-forming properties of the photosensitive composition, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol methyl ethyl ether, hexafluoro -2-propanol, 2,2,3,3,4,4,5,5-octafluoro-1-pentanol and 1H,1H,7H-dodecafluoro-1-heptanol are preferred.

The content of the solvent in the photosensitive composition is, for example, 98.9 wt% or less, preferably 94 wt% or less. The lower limit of the solvent content is not particularly limited, and is, for example, 15 wt%. The photosensitive composition does not need to contain a solvent.

[device]
As shown in FIG. 1, the device 10 of this embodiment includes a substrate 1 and a water-repellent film 2. The water-repellent film 2 is disposed on the substrate 1 and is in contact with the substrate 1. As described later, the water-repellent film 2 is a developed film obtained by developing a photosensitive film made from the above-described photosensitive composition. Therefore, the water-repellent film 2 contains the above-mentioned polymer (P).

The water-repellent film 2 has an opening 5, and the opening 5 exposes a part of the surface of the substrate 1, for example. The water-repellent film 2 may have a plurality of openings 5. The opening 5 penetrates the water-repellent film 2 in the thickness direction. The opening 5 may have the shape of a hole or a groove. When the opening 5 has the shape of a hole, the opening 5 has, for example, a circular shape in a plan view. In the water-repellent film 2, one or more openings 5 may be formed in a predetermined pattern.

When the opening 5 has a circular shape in plan view, the diameter of the opening 5 is, for example, 1 to 1000 μm, preferably 10 to 500 μm. When the opening 5 has the shape of a groove, the width of the opening 5 is, for example, 1 to 2000 μm, preferably 10 to 1000 μm. When the water-repellent membrane 2 has a plurality of openings 5, the distance between two adjacent openings 5 is, for example, 1 to 2000 μm, preferably 1 to 1000 μm, more preferably 10 to 1000 μm, and Preferably it is 10 to 500 μm.

The thickness of the water-repellent film 2 is not particularly limited, and is, for example, 0.01 to 100 μm, preferably 0.1 to 50 μm.

As the substrate 1, for example, a glass plate; a thermoplastic sheet containing polypropylene, polyethylene, polycarbonate, polymethyl methacrylate, polystyrene, polyimide, polyamideimide, polyamide, etc.; a silicon wafer; a metal containing stainless steel (SUS), aluminum, etc. Plate: Examples include a laminate of a metal foil such as copper foil and a resin substrate. From the viewpoint of heat resistance, the substrate 1 is preferably a glass plate, particularly a quartz glass plate.

The composition of the water-repellent film 2 is, for example, the same as that of the photosensitive composition described above, except that it contains almost no solvent. The water-repellent film 2 includes, for example, in addition to the polymer (P), at least one selected from the group consisting of the above-mentioned photoacid generator and photobase generator.

The content of the polymer (P) in the water-repellent film 2 is, for example, 1 wt% or more, preferably 5 wt% or more. The content of the polymer (P) in the water-repellent film 2 may be 99.9 wt% or less, or 80 wt% or less. The content of the photoacid generator in the water-repellent film 2 is, for example, 0.1 wt% to 10 wt%, preferably 1 wt% to 5 wt%. The content of the photobase generator in the water-repellent film 2 is, for example, 0.1 wt% to 10 wt%, preferably 1 wt% to 5 wt%.

The water-repellent film 2 has high water-repellency by containing the polymer (P). The contact angle of the water-repellent film 2 with respect to water is, for example, 60 degrees or more, preferably 90 degrees or more. The upper limit of the contact angle of the water-repellent film 2 with respect to water is not particularly limited, and may be, for example, 130 degrees or 110 degrees. The contact angle of the water-repellent film 2 can be measured in accordance with the "sessile drop method" defined in JIS R3257:1999. Specifically, the contact angle of the water-repellent film 2 can be measured by the following method. First, a syringe equipped with a needle is held at a position where the tip of the needle does not come into contact with the water-repellent membrane 2. A droplet of 2 μL (distilled water) is dispensed from the tip of the needle, and while the droplet is held at the tip of the needle, the syringe is lowered to bring the droplet into contact with the water-repellent film 2. The syringe is raised, only the droplet is placed on the membrane, and the contact angle of the droplet is measured using a commercially available contact angle meter.

The device 10 provided with the water-repellent membrane 2 is suitable for biochips, microchannel chips, and the like. A specific example of the microchannel chip is a microreactor. As an example, the device 10 of this embodiment can be used as a biochip.

Next, a method for manufacturing the device 10 will be described. First, as shown in FIG. 2A, the above-described photosensitive composition is applied to the substrate 1 to produce the photosensitive film 3. The method of applying the photosensitive composition to the substrate 1 is not particularly limited, and examples thereof include a spray method, a roll coating method, a spin coating method, a bar coating method, and the like. The photosensitive film 3 can be produced, for example, by applying a photosensitive composition to the substrate 1 and then drying the photosensitive composition. Drying conditions for the photosensitive composition are not particularly limited, and for example, the photosensitive composition may be dried by heating the photosensitive composition. The photosensitive composition may be heated, for example, at a temperature of 50° C. to 120° C. for 10 to 2000 seconds. The thickness of the photosensitive film 3 is, for example, the same as the thickness of the water-repellent film 2.

Next, a part of the photosensitive film 3 is exposed. Examples of methods for exposing a portion of the photosensitive film 3 include the following method. First, as shown in FIG. 2B, a mask 20 is placed on the photosensitive film 3. The mask 20 has an opening 25 through which a part of the surface of the photosensitive film 3 is exposed. Next, the light source 30 irradiates the surface of the mask 20 with light. Thereby, the surface of the photosensitive film 3 exposed through the opening 25 of the mask 20 can be exposed. The light irradiated from the light source 30 can be selected depending on the type of photoacid generator or photobase generator contained in the photosensitive film 3, for example, from the group consisting of ultraviolet rays, visible light, infrared rays, electron beams, and radiation. It is at least one selected and preferably includes ultraviolet rays. The wavelength of the light emitted from the light source 30 is, for example, 100 to 500 nm, preferably 200 to 450 nm, and more preferably 365 nm. The exposure amount of light emitted from the light source 30 is, for example, 5 to 10,000 mJ/cm ² . Examples of the light source 30 include semiconductor light emitting devices, preferably light emitting diodes (LEDs), superluminescent diodes (SLDs), and laser diodes (LDs). Light source 30 may be a high pressure mercury lamp.

In the exposed portion of the photosensitive film 3, acid is generated from the photoacid generator or base is generated from the photobase generator. The resulting acid or base decomposes the structural unit (A) contained in the polymer (P). The decomposition of the structural unit (A) is represented by, for example, the reaction formula (4) below.

Next, if necessary, the exposed photosensitive film 3 is subjected to heat treatment. In the heat treatment, known heating devices such as a hot plate and an oven can be used. The heat treatment is performed, for example, at 60° C. to 200° C. for 60 to 600 seconds.

Next, the water-repellent film 2 is formed by developing the photosensitive film 3. The development of the photosensitive film 3 is performed, for example, by removing the exposed portion of the photosensitive film 3 with a developer. As the developer, for example, one that can dissolve the decomposition product of the polymer (P) produced in the reaction formula (4) above, but hardly dissolves the polymer (P), is used. The developer is preferably basic, particularly weakly basic. Examples of the developer include propylene glycol monomethyl ether acetate (PGMEA), N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, 1,3-dimethyl-2-imidazolidinone, Organic solvents such as dimethyl sulfoxide, dimethyl sulfide, dimethyl sulfone, tetramethyl urea, diglyme, triglyme, tetrahydrofuran, dioxane, cyclohexane, toluene, xylene, isoamyl acetate, dimethyl ammonium, halogenated hydrocarbons; sodium hydroxide, potassium hydroxide, etc. Aqueous solutions of organic bases such as propylamine, butylamine, monoethanolamine, tetramethylammonium hydroxide, choline, etc. can be used. The development process can be performed by, for example, a paddle method, a dipping method, or a shower method. The development processing time is, for example, 30 to 180 seconds. After the development process, the obtained water-repellent film 2 may be washed with water. The cleaning time for the water-repellent film 2 is, for example, 30 to 90 seconds. After performing the cleaning treatment, the water-repellent film 2 may be dried.

EXAMPLES The present invention will be explained in more detail below using Examples and Comparative Examples, but the present invention is not limited thereto.

(Example 1)
First, under an argon atmosphere at room temperature (20°C ± 15°C), 22.6 g of perfluoro-2-methylene-4-methyl-1,3-dioxolane (compound represented by formula (M2)) was added to 50 mL of 1 , 1,1,2,2,3,4,5,5,5-decafluoropentane (Vertrell XF, manufactured by Mitsui Chemours Fluoro Products). While maintaining an argon atmosphere, 0.155 g of perfluorobenzoyl peroxide was added to the obtained solution and mixed with stirring. Dissolved oxygen was then removed from the solution by freeze degassing. The solution was heated to 40° C. while stirring and reacted for 72 hours. The resulting reaction mixture was added to 300 mL of chloroform. The precipitate produced by this operation was collected by filtration. The obtained filtrate was a polymer of perfluoro-2-methylene-4-methyl-1,3-dioxolane (polymer (P)). The yield of the polymer was 19.2 g, and the yield was 81.0%.

Next, 10 g of the obtained polymer was dissolved in 90 mL of 1,1,1,2,2,3,4,5,5,5-decafluoropentane. The obtained solution and 0.4 g of tris(4-methylphenyl)sulfonium nonafluorobutane sulfonate (WPAG-638 manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a photoacid generator were added into a glass vial (200 mL). A homogeneous solution was obtained by sufficiently stirring these. The photosensitive composition of Example 1 was prepared by filtering the obtained solution through a PTFE filter with a pore size of 0.20 μm.

(Comparative example 1)
First, a polymer consisting of structural units represented by the following formulas (5) to (7) was prepared. The content of the structural unit represented by formula (5) in the polymer is 63 mol%, the content of the structural unit represented by formula (6) is 26 mol%, and the content of the structural unit represented by formula (7) is 63 mol%. The content of the structural units was 11 mol%.

Next, 100 parts by mass of the above polymer, 2.5 parts by mass of triphenylsulfonium nonafluorobutanesulfonate as a photoacid generator, 0.1 part by mass of surfactant R-08 (manufactured by DIC), and 0 parts by mass of tripentylamine. The photosensitive composition of Comparative Example 1 was prepared by mixing 0.2 parts by weight of salicylic acid, 0.09 parts by weight of salicylic acid, and 600 parts by weight of ethyl lactate (EL).

(Developability)
The developability of the photosensitive compositions of Example 1 and Comparative Example 1 was evaluated by the following method. First, a photosensitive composition was applied onto a 4-inch quartz glass plate. The photosensitive composition was applied by spin coating at 1000 rpm for 30 seconds. Next, the photosensitive composition was heated at 100° C. for 300 seconds using a hot plate to form a photosensitive film.

Next, the photosensitive film was exposed to light through a mask (a mask capable of forming a circular hole pattern with a diameter of 50 μm). At this time, a high-pressure mercury lamp was used as a light source, and the exposure amount was adjusted to 800 mJ/cm ² . In the exposed portion of the photosensitive film, acid was generated from the photoacid generator and the polymer was decomposed. After exposure of the photosensitive film, the photosensitive film was heated at 120° C. for 120 seconds using a hot plate to promote decomposition of the polymer.

Next, the exposed photosensitive film was subjected to a development operation. As the developer, a 2.38 wt % aqueous solution of tetramethylammonium hydroxide (TMAH) was used. The development process was performed for 60 seconds by the dipping method. In this way, a developed film was formed. The thickness of the developed film was 3.0 μm. The developed film was washed with water and then dried at 120° C. for 60 seconds.

Next, the developed film was observed with a microscope (VHX DIGITAL MICROSCOPE, manufactured by KEYENCE). When it was confirmed that holes with a diameter of 50 μm were opened in the developed film, the developability of the photosensitive composition was judged to be good (◯). When a hole with a diameter of 50 μm was not opened in the developed film or a pattern was not formed in the developed film, the developability of the photosensitive composition was judged to be poor (×). The results are shown in Table 1.

(contact angle)
The developed films prepared from each of the photosensitive compositions of Example 1 and Comparative Example 1 were evaluated for contact angle with water by the method described above. The results are shown in Table 1.

As can be seen from Table 1, the photosensitive composition containing the polymer (P) had good developability. Furthermore, the developed film formed from the photosensitive composition containing the polymer (P) had a large contact angle with water and had high water repellency. A developed film having such high water repellency is suitable for applications such as biochips and microchannel chips.

The developed film formed from the photosensitive composition of this embodiment is suitable for applications such as biochips and microchannel chips.

1 Substrate 2 Water-repellent film (developed film)
3 Photosensitive film 5 Opening 10 Device 20 Mask 25 Opening 30 Light source

Claims (8)

A polymer (P) containing a structural unit represented by the following formula (1) and containing substantially no hydrogen atoms ,
a photoacid generator ;
A photosensitive composition comprising.
However, the photosensitive composition does not contain any polymer other than the polymer (P).

[In formula (1), R _ff ¹ to R _ff ⁴ each independently represent a fluorine atom, a perfluoroalkyl group having 1 to 7 carbon atoms, or a perfluoroalkyl ether group having 1 to 7 carbon atoms. R _ff ¹ and R _ff ² may be connected to form a ring. ] The photosensitive composition according to claim 1 , wherein the polymer (P) is perfluorinated. The photosensitive composition according to claim 1 or 2 , wherein the polymer (P) contains the largest amount of the structural unit on a molar basis . The photosensitive composition according to any one of claims 1 to 3 , wherein the structural unit is represented by the following formula (2).

Applying the photosensitive composition according to any one of claims 1 to 4 to a substrate to produce a photosensitive film;
exposing a part of the photosensitive film;
Developing the photosensitive film;
A method of manufacturing a device, including: 6. The manufacturing method according to claim 5 , wherein the development of the photosensitive film is performed by removing the exposed portion of the photosensitive film with a developer. The manufacturing method according to claim 6 , wherein the developer is basic. The manufacturing method according to any one of claims 5 to 7 , wherein a part of the photosensitive film is exposed to ultraviolet light.

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