JP2017003877A - Reaction development image forming method, photosensitive resin composition used for reaction development image forming method, and substrate and structure produced by reaction development image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition that is usable in a low wavelength region, used in leading-edge lithography, and serves as inexpensive photoresist materials, and a reaction development image forming method and the like using the same.SOLUTION: The present invention provides a photosensitive resin composition used for reaction development image forming method, the composition comprising an alicyclic polycarbonate resin having a constitutional unit represented by formula (1), and a photosensitizer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a photosensitive resin composition for photolithography containing a polycarbonate resin having a specific structure, and a reaction development image forming method for forming a fine pattern using the same.

For microfabrication required for semiconductor substrates, FPDs, and printed wiring board circuits, a photolithography method using an organic polymer as a resist is used, and various types of polymers have been developed depending on the target pattern shape, size, and light source. ing. In particular, acrylic polymers composed of special monomers with functions such as acid dissociation, substrate adhesion, and etching resistance are used to form circuits on the order of tens of nanometers in the cutting-edge semiconductor field. (Patent Documents 1 to 3).
These acrylic polymers introduce bulky alicyclic structures such as norbornane groups and adamantyl groups in the side chains to impart etching resistance, and improve adhesion to substrates and solubility in developers. It is used as a ternary or higher copolymer, for example, by introducing a lactone structure into the monomer, and the synthesis procedure of each monomer is complicated.
In addition, the above-mentioned acrylic polymer is also required to have a narrow molecular weight distribution and high-purity purification in order to increase the resolution. Therefore, there is a problem that the cost of the polymer increases due to purification cost and yield reduction. In addition, the above-mentioned acrylic polymer has a problem that it is a high-cost material because of the speciality and complexity of processes in monomer synthesis and polymer production.

On the other hand, as a low-cost technique, a reaction development image forming method using a commercially available engineering plastic is known (Patent Document 4, Non-Patent Documents 1 and 2).
In this reaction development image forming method, a commercially available engineering plastic is mixed with a photosensitizer and a solubility adjusting agent, and coated on a substrate by a cast method, a spin coat method, or the like to form a photoresist layer. Then, through a mask having a defined pattern, for example, exposure to ultraviolet light is performed to activate the photosensitive agent in the polymer, and in the development process, the polymer main chain is decomposed and exposed with a developer containing an alkali or an organic solvent. In this lithography method, a pattern is formed by washing a portion with a developer.
In addition, methods using polycarbonate for the reaction development image forming method are known (Patent Documents 5 to 6 and Non-Patent Documents 1 and 2).
In general, circuit pattern formation by lithography has been aimed at improving performance by shortening the exposure wavelength and making it finer, so lithography requires a useful photoresist layer for shorter wavelengths. is there. However, the polycarbonates exemplified in the above documents contain aromatic structures including bisphenol type. As described above, the polycarbonate described in the above document has an aromatic ring, and thus has insufficient light transmittance, and is used for ultraviolet light in a wavelength range of 365 nm or less that is actually used in the most advanced photolithography. There is a problem that it cannot be practically applied to applications and fields that require a finer structure and finer wiring.

Japanese Patent No. 2881969 Patent 3042618 JP 2002-145955 A JP 2003-76013 A JP 2009-271155 A JP 2012-234104 A

J. et al. Microlith. Microfab. Microsys. , 3, 159-167 (2004) Polymer Papers, Vol. 67, no. 8,477-488 (2010)

  The present invention is not limited to a wavelength region (g-line (436 nm) to i-line (365 nm)) that is usually used in lithography of semiconductors, liquid crystals, printed wiring boards, and the like. It is an object to provide a photosensitive resin composition as a photoresist material that can be used at a wavelength of 193 nm (ArF excimer laser) to 248 nm (KrF excimer laser) and a reaction development image forming method using the same. It is said.

As a result of intensive studies in order to solve the above-mentioned problems, the inventors have developed an argon fluoride (ArF) excimer used in state-of-the-art photolithography as a polycarbonate having a specific structure that can be produced by a general polycarbonate production method. Reactive development image forming method using photosensitive resin composition containing alicyclic polycarbonate and photosensitizer having sufficient transparency to light irradiated from short wavelength light source such as laser and krypton fluoride (KrF) excimer laser As a result, the present invention was completed by developing an accurate and inexpensive microfabrication method.
That is, the present invention is as follows.

[1]
A photosensitive resin composition used for a reaction development image forming method, comprising an alicyclic polycarbonate resin having a structural unit represented by the formula (1), and a photosensitive agent.
(Wherein X is a C5-C20 cycloaliphatic substituent having one or more ring structures not containing an aromatic ring, and the cycloaliphatic substituent has a bridged structure and / or a spiro structure. May contain a hetero atom,
R1 and R2 represent the same or different alkyl group having 1 to 4 carbon atoms, n1 and n2 represent the same or different integers of 0 to 2, and Z represents an oxygen atom or a single atom. Represents a bond. )

[2]
In the formula (1), the cycloaliphatic substituent represented by X is selected from the group consisting of the following (a-1) to (a-9), [1] .
(N4 represents an integer of 0 to 3, n5 represents an integer of 1 to 6 which may be the same or different, n6 represents an integer of 0 to 1 which may be the same or different, and R3 represents 1 to 2 carbon atoms. R4 represents a methylene group or a single bond, and a broken line means a bond with an adjacent group.)

[3]
The photosensitive resin composition according to [1] or [2], wherein the photosensitive agent contains a quinonediazide compound.

[4]
A reaction development image forming method comprising the following steps:
Process A: The process of forming a photoresist layer using the photosensitive resin composition in any one of [1]-[3] Process B: The process of exposing the said photoresist layer using light or a radiation. And Step C: a reaction development image forming method including a step of developing the photoresist layer using a developer, and washing after developing.

[5]
The reactive development image forming method according to [4], wherein the light or radiation has a wavelength of 248 nm or less.

[6]
The reactive development image forming method according to [4], wherein the light is irradiated by an ArF excimer laser.

[7]
The reaction development image forming method according to any one of [4] to [6], wherein the developer contains an alcohol compound or an ether compound.

[8]
The reaction development image forming method according to any one of [4] to [7], wherein the developer includes at least one selected from the group consisting of sodium hydroxide, potassium hydroxide, and tetramethylammonium hydroxide.

[9]
In 100 mass% of the developer, alkali compound / alcohol compound / ether compound = 1 to 30 mass% / 20 to 90 mass% / 1 to 50 mass%, and the total value is 100 mass%, [7] The reaction development image forming method according to [8].

[10]
A semiconductor substrate, a liquid crystal substrate, or a printed wiring board manufactured using the reactive development image forming method according to any one of [4] to [9].

[11]
[4] to [9] A structure having a diffraction grating, a lens material, or an optical waveguide including a finely shaped region formed by using the reactive development image forming method according to any one of [9] to [9].

  According to the present invention, not only the wavelength range (g-line (436 nm) to i-line (365 nm)) normally used in lithography of semiconductors, liquid crystals, printed wiring boards, etc., but also the wavelength range used in state-of-the-art lithography, such as wavelength It can be used at 193 nm (ArF excimer laser) to 248 nm (KrF excimer laser), and can provide an inexpensive photoresist material and its method.

2 is a SEM photograph of the photoresist of Example 1. FIG. It is a figure which shows the SEM photograph of the photoresist of Example 9. FIG.

  Hereinafter, the present invention will be described in detail.

  The present invention includes a photosensitive resin composition for photolithography having a polycarbonate having a specific structure and a photosensitive agent, and a reaction development image forming method for forming a fine pattern using the photosensitive resin composition.

The reactive development image forming method includes the following steps.
Process 1: Adjustment process of photosensitive resin composition Process 2: Photoresist layer formation process (process A)
Process 3: Photosensitive process (Process B)
Process 4: Development and washing process (Process C)

[Step 1: Step of preparing photosensitive resin composition]
The photosensitive resin composition of the present invention includes an alicyclic polycarbonate resin and a photosensitive agent, and may further include a solvent and the like.

(Alicyclic polycarbonate resin)
The alicyclic polycarbonate resin used in the present invention has a structural unit represented by the formula (1).
(Here, X is a C5-C20 cycloaliphatic substituent having one or more ring structures not containing an aromatic ring.
In the cycloaliphatic substituent, the ring structure may contain a bridged structure or a spiro structure, and the cycloaliphatic substituent may have O or N heteroatoms. And R1 and R2 represent the C1-C4 alkyl group which may be the same or different, n1 and n2 represent the integer of 0-2 which may be the same or different. Z represents an oxygen atom or a single bond. )

  The structural unit of the formula (1) may be a single structure or may be composed of two or more types. The structural unit of the above formula (1) as the repeating unit is not particularly limited because it is appropriately determined depending on the physical properties of the target patterning (for example, shape, heat resistance, solubility in a developing solvent, refractive index, etc.).

R1 and R2 in Formula (1) represent the C1-C4 alkyl group which may be same or different as mentioned above, and are specifically illustrated below. In addition, a broken line means the coupling | bonding with an adjacent group.
As described above, n1 and n2 representing an integer of 0 to 2 are preferably 1.

As described above, the structure X in the formula (1) is an aliphatic substituent having 5 to 20 carbon atoms having one or more ring structures that do not contain an aromatic ring. A structure may be included. Examples of the aliphatic compound having a ring structure include, but are not limited to, the following.
(N4 represents an integer of 0 to 3, n5 represents the same or different integer of 1 to 6, n6 represents the same or different integer of 0 to 1. R3 represents 1 carbon atom. Represents an alkyl group of ˜2, R4 represents a methylene group or a single bond, and a broken line means a bond with an adjacent group.)

Examples of the structure (a-1) include cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, and cyclodecane. Examples of the cyclic structure (a-2) to (a-5) include a structure in which a plurality of rings selected from cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, and cyclodecane are combined.
For example, when both of the cyclic structures of (a-2) are cyclohexane skeletons, a decalin skeleton is obtained, and when both of the cyclic structures of (a-3) are cyclopentane skeletons, spiro [4.4] nonane is obtained. Examples of (a-6) include norbornane (bicyclo [2.2.1] heptane) and 1,1,7-trimethyl-bicyclo [2.2.1] heptane structures. (A-7) is exemplified by a tricyclo [5.2.1.0 ^2,6 ] decane structure. (A-8) is exemplified by a pentacyclopentadecane structure. Examples of (a-9) include adamantane, methyladamantane, dimethyladamantane, and ethyladamantane. The structures (a-1) to (a-9) are not limited to those exemplified.

In the skeletons of (a-1) to (a-9), a methylene (—CH ₂ —) group may be substituted with an oxa (—O—) group. For example, as shown in the following formula, hexahydrofuro [3,2-b] furan skeleton, 2,4,8,10-tetraoxaspiro [5.5] undecane skeleton, 1,3-dioxane-5 -Ethyl skeleton, 1,4-dioxane skeleton, 7-oxabicyclo [2.2.1] heptane skeleton, octahydro-1H-4,7-epoxyindene skeleton and the like are exemplified, but not limited thereto. .
In the skeletons (a-1) to (a-9), the methylene (—CH ₂ —) group is substituted with a secondary amine (—NH—), and the tertiary carbon is substituted with a tertiary amine. Also good.

As the alicyclic polycarbonate resin represented by the formula (1), those having the following repeating structure are particularly suitable. These repeating structures can be used singly or in combination. Further, two or more kinds of alicyclic polycarbonate resins of the formula (1) having different structures can be used.
Moreover, it is also possible to use other PC resin together with the alicyclic polycarbonate resin represented by Formula (1). For example, the alicyclic polycarbonate resin and the aliphatic polycarbonate resin other than those represented by the formula (1) are included in the total resin in an amount of 50% by mass or less, preferably 20% by mass or less, more preferably 10% by mass or less. Is possible. In particular, an aliphatic polycarbonate having a low glass transition temperature may not be able to form a photoresist layer. Moreover, it is also possible to include 1 mass% or less of aromatic PC resin.

The polystyrene-reduced mass average molecular weight (hereinafter referred to as “Mw”) measured by gel permeation chromatography (GPC) of the alicyclic polycarbonate resin of the present invention is preferably 1,000 to 500,000, more preferably 3. , 000-300,000. Moreover, the ratio (Mw / Mn) of the above Mw and the polystyrene-equivalent number average molecular weight (hereinafter referred to as “Mn”) measured by GPC is usually 1 to 10, preferably 1 to 5.
In addition, it is preferable that the glass transition temperature of the alicyclic polycarbonate resin of this invention is at least 40 degreeC or more.

(Photosensitive agent)
The photosensitizer used in the present invention is, for example, a quinonediazide compound represented by the following formula. The following quinonediazide compound has at least one quinonediazide structure, and generates an acid upon irradiation with actinic radiation.
In the formula, each Q independently represents an -OD group (wherein D represents a hydrogen atom or an organic group having a quinonediazide structure), an alkyl group or an alkoxy group. This alkyl group is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. The alkoxy group is preferably an alkoxy group having 1 to 3 carbon atoms, more preferably a methoxy group. p represents an integer of 1 to 3.
The organic group having a quinonediazide structure is preferably a 1,2-benzoquinonediazide-4-sulfonyl group, a 1,2-naphthoquinonediazide-4-sulfonyl group, a 1,2-naphthoquinonediazide-5-sulfonyl group, 2-quinonediazide-6-sulfonyl group, 2,1-naphthoquinonediazide-4-sulfonyl group, or 2,1-naphthoquinonediazide-5-sulfonyl group, more preferably 1,2-naphthoquinonediazide-4-sulfonyl group or 1,2-naphthoquinonediazide-5-sulfonyl group, most preferably 1,2-naphthoquinonediazide-5-sulfonyl group. The —OD group is preferably located in the para position relative to R11.

R11 is a single bond, or-(R13) m3- (R14) m4- (wherein R13 represents an arylene group, R14 represents an alkylene group, m3 represents 0 or 1, m4 represents 0 or 1) Represents.) The arylene group is preferably a phenylene group, and the above-described alkylene group preferably represents an alkylene group having 1 to 10 carbon atoms, more preferably —C (CH ₃ ) ₂ —.
R12 represents a hydrogen atom, an alkyl group, or —COR15 (wherein R15 represents an alkyl group or an aryl group). These alkyl groups are preferably alkyl groups having 1 to 10 carbon atoms, and the above aryl group is preferably a phenyl group.
m1 represents an integer of 0 to 3, and m2 represents an integer of 1 to 4. However, m1 + m2 = 4.

  The compounding quantity of a photosensitizer is 0.01-0.5 mass times (1-50 mass parts with respect to 100 mass parts of alicyclic polycarbonate resins) with respect to alicyclic polycarbonate resin, Preferably 0.05- 0.4 mass times, More preferably, it is 0.1-0.3 mass times. If the blending amount of the photosensitizer is less than this, it may not be possible to develop after irradiation with radiation. Photosensitizers can be used alone or in combination of two or more.

(solvent)
The photosensitive resin composition containing the alicyclic polycarbonate resin is preferably dissolved with a solvent. By making it into a solution, it can be easily applied onto the substrate by bar coating, spin coating, droplets, etc., and the film thickness can be easily controlled when spin coating is performed by adjusting the concentration. Because you can. A solvent uses 1-100 mass times with respect to alicyclic polycarbonate resin, More preferably, 2-50 mass times is used. If the concentration of the photosensitive resin composition is higher than this, the solution viscosity is high and the handling property may be lowered.

  The solvent is not particularly limited as long as it can dissolve the alicyclic polycarbonate resin. Halogen compounds such as dichloromethane, chloroform, carbon tetrachloride, dichloroethane, dichloropropane, chlorobenzene and dichlorobenzene, aromatic compounds such as benzene, toluene, xylene and trimethylbenzene, ether compounds such as dioxane, tetrahydrofuran and diisopropyl ether, 2-pentanone , Linear ketones such as 2-hexanone, cyclic ketones such as cyclopentanone and cyclohexanone, esters such as ethyl acetate and ethyl lactate, propylene glycol mono such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate Ethyl acetates such as alkyl acetates, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate Glycol monoalkyl ether acetates, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl Diethylene glycol alkyl ethers such as ether, N-methyl-2-pyrrolidone, butyrolactone, N, N′-dimethylacetamide, dimethylformamide, dimethylsulfoxide and the like are preferable. These solvents can be used alone or in admixture of two or more.

  In the photosensitive resin composition of the present invention, conventional additives can be used in addition to the above-described components as long as the effects of the present invention are exhibited. Specific examples include a sensitizer, an antihalation agent, a storage stabilizer, an antifoaming agent, a coupling agent, a surfactant, and a leveling agent.

[Step 2: Photoresist layer forming step]
A photoresist layer formation process is a process of forming a photoresist layer by apply | coating the photosensitive resin composition on various board | substrates.

The board | substrate used by this invention is copper foil, aluminum, a silicon wafer, glass, a plastics, etc., It does not specifically limit, You may perform the process by a silane coupling process or a piranha solution as pre-processing.
Application on a substrate is usually performed by dipping (dipping), spraying (spray coating), roll coating, bar coating, or spin coating. The film thickness depends on the viscosity of the photosensitive resin composition, the resin content, and the spin coating speed. The photosensitive resin composition of the present invention can form a patterned structure by forming a photoresist layer having a thickness of 0.05 to 500 μm, preferably 0.1 to 100 μm, more preferably 0.2 to 10 μm. .

  After the photosensitive resin composition is applied to the substrate, it is usually baked in the temperature range of 50 to 140 ° C. to evaporate the solvent. At this time, an oven or a hot plate can be used. The operating temperature may be selected at a temperature at which the solvent is easily vaporized, but it is preferably carried out below the glass transition temperature of the alicyclic polycarbonate resin to be used.

[Step 3: Photosensitive step]
The photosensitive process is a process in which a photoresist layer containing the photosensitive resin composition is irradiated with light or radiation having a specific wavelength to cause a chemical difference between an exposed part and an unexposed part.

The photosensitive resin composition is coated on a substrate and then exposed. In exposure, a generally known exposure apparatus can be used. For example, it is preferable to use a contact or non-contact exposure apparatus. Exposure is divided into an exposed part and an unexposed part through direct irradiation or a photomask. In the exposure, light having a wavelength range of 150 to 500 nm can be used. Among them, g-line (436 nm) and i-line (365 nm) can be used, and a short wavelength light source of KrF excimer laser (248 nm) and ArF excimer laser (193 nm) can be used. X-rays, electron beams, and 13.5 nm extreme ultraviolet light can also be used. That is, the wavelength range in which the photosensitive resin composition of the present invention can be exposed is 500 nm or less. For example, low wavelength light of 248 nm or less and extremely low wavelength light of 193 nm or less can be used.
The exposure amount is appropriately determined according to the structure and blending ratio of a photosensitizer such as an alicyclic polycarbonate resin and a quinonediazide compound, and is not particularly limited.

[Step 4: Development and washing step]
The development and cleaning steps are steps in which the substrate coated with the photoresist layer that has undergone step 3 is exposed and contacted with a developer after exposure to remove either exposed / unexposed portions and patterning.
After exposure, the photoresist layer functions as a positive or negative photoresist. In order to remove an exposed portion or an unirradiated region of the photoresist, the photoresist layer is contacted with a developing solution and developed. Specific examples of the contact method include immersion or spraying, but are not limited thereto.
The positive type and the negative type can be selected by a combination of a developer and an alicyclic polycarbonate. Specifically, an alicyclic polycarbonate whose alicyclic structure is generally composed of only hydrocarbons is easy to form a negative type, and an alicyclic structure that contains a heteroelement such as oxygen or nitrogen. Cyclic polycarbonate tends to form a positive mold. Based on the combination of the developer and the alicyclic polycarbonate, a positive type and a negative type can be selected.

  The developer is a solution containing at least one selected from water, an alkali compound, and an organic solvent. Alkali compounds include inorganic base compounds and organic base compounds. Examples of the inorganic base compound include sodium hydroxide, potassium hydroxide, lithium hydroxide and the like, and examples of the organic base compound include trimethylammonium hydroxide, triethylamine, tripropylamine, tributylamine, triethanolamine, tripropanolamine, Examples include tributanolamine, pyridine, aniline and the like. As the organic solvent, an alicyclic polycarbonate resin or a solvent capable of dissolving a photosensitizer is used. Specifically, alcohol compounds such as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, glycol compounds such as ethylene glycol, diethylene glycol, propylene glycol, dioxane, tetrahydrofuran, diethyl ether, dipropyl ether, methyl Examples include ether compounds such as butyl ether, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate, acetone, methyl ethyl ketone, cyclohexanone, N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide, tetramethyl urea, and butyrolactone. These can be used in any combination. Preferably, developability is improved by a developer containing an alkali compound, an alcohol compound, and an ether compound. Preferably, alkali compound / alcohol compound / ether compound = 1-30% by mass / 20-90% by mass / 1-50% by mass (however, the total value is 100% by mass), more preferably 1-20% by mass / 40 to 80% by mass / 10 to 40% by mass (however, the total value is 100% by mass). If it is the above-mentioned ratio, the difference in the dissolution rate ratio between the exposed part and the unexposed part is large, so that the resolution is improved and the developing speed is also improved. The development stop after the development is usually performed by washing the developer by immersion or spraying in water or a slightly acidic aqueous solution.

  The main field of application of the present invention is the manufacture of micro / nanoelectronic and optoelectronic circuits and components. In this field, the photosensitive resin composition is used as a temporary photoresist mask as well as a permanent structure, for example, an insulating layer, a protective film or a non-conductive layer, a dielectric layer or an alignment film in a liquid crystal display element, an optical member It can be used for a diffraction grating or the like. The film thickness and shape are not particularly limited because they depend on each application.

  Hereinafter, the present invention will be illustrated with examples, but the embodiment can be changed as long as the effects of the present invention are exhibited.

In this example, a photoresist layer was formed by the following method and observed. First, the photosensitive resin composition of each Example was filtered with a filtration membrane having a pore size of 3 μm to produce a photoresist layer as follows. The above-mentioned photosensitive resin composition is applied on the surface of the shine surface or matte surface of a 10 cm × 10 cm copper foil (JX Nippon Mining & Metals Co., Ltd., JTCS 35 μm) by a spin coating method. It was.
In addition, the copper foil which is a board | substrate is pre-processed by the method of an Example description what is described about a board | substrate process.
Subsequently, after the photosensitive resin composition coating film dried at 90 ° C. for 5 minutes in an infrared hot air dryer is cut into 2.5 cm × 2.5 cm, a test pattern for a photomask (positive type: A 5-120 μm line and space pattern or a negative type: 10-200 μm line and space pattern) is placed, and an exposure is performed to obtain an image using a 2 kW ultra-high pressure mercury lamp irradiation device (JP-2000-EXC manufactured by Oak Seisakusho). Irradiated in quantity.
The coating film after irradiation was immersed or sonicated in a predetermined developer, washed with pure water, dried with an infrared lamp, and the resolution was observed. The pattern in the formed photoresist layer was observed with a scanning electron microscope (JEOL, scanning electron microscope: JSM-6390LV, acceleration voltage: 1.2 kV), and the line width at the development limit was defined as the resolution.

Example 1
0.5 g of cyclohexanedimethanol polycarbonate (glass transition temperature 45 ° C.) represented by the formula (7) is added to 4.5 g of 1,4-dioxane (manufactured by Wako Pure Chemical Industries, Ltd., first grade, hereinafter referred to as “DOX”). After being added and stirred for about 1 hour at 50 ° C. with a stirrer to dissolve, diazonaphthoquinone photosensitizer BADNQ3 (produced by Toyo Gosei Co., Ltd., 6-diazo-5,6-dihydro-5-oxo-) was used as a photoacid generator. 1-Naphthalenesulfonic acid 1,1 ′-[[1- [4- [1- [4-[[(6-diazo-5,6-dihydro-5-oxo-1-naphthalenyl) sulfonyl] oxy] phenyl] -10 g of -1-methylethyl] phenyl] ethylidene] di-4,1-phenylene] ester (CAS number: 14541-99-9) was added, stirred at room temperature for about 1 hour, degassed and photosensitized. A functional resin composition was prepared.

This solution is applied onto an electrolytic copper foil (matt surface) having a thickness of 35 μm by spin coating (300 rpm / 10 seconds + 500 rpm / 30 seconds), and pre-baked (90 ° C., 5 minutes) with a far infrared hot air circulating dryer. Thereafter, a photosensitive polycarbonate coating film having a film thickness of about 5.0 μm was obtained.
This was irradiated with light in the i-line to g-line band through a negative photomask made of PET by an ultraviolet exposure machine (Oak). The exposure amount measured with an illuminometer for the i-line band was 400 mJ / cm ² .
After the exposure, 10 g of tetramethylammonium hydroxide (TMAH) methanol solution (manufactured by Tokyo Kasei Kogyo Co., Ltd.) / DOX = 2/1 (mass ratio) is used at room temperature under ultrasonic treatment using 20 g of developer. Development was carried out and washed with 100 g of ion exchange water for 1 minute. As a result, a negative image was obtained. The development time at this time was 6 minutes 50 seconds. The resolution was 35 μm with a line and space pattern (Table 1). An SEM photograph of this photoresist is shown in FIG.

(Examples 2 to 8)
The same operation as in Example 1 was carried out except that the substrate, substrate processing, developer composition, development temperature, development conditions, and development time were changed to the conditions shown in Table 1 (Table 1).

In addition, the meaning of the term in Table 1 and following Table 2 or less is as follows.
-Resin; CHDM-PC: Cyclohexane dimethanol polycarbonate ISB-PC: Isosorbide polycarbonate-Photosensitizer; BADNQ2 and BADNQ3: See formula (10) described later-Substrate treatment;
Piranha treatment: The substrate is immersed in a stirred solution of 9 mL of 30% hydrogen peroxide and 21 mL of concentrated sulfuric acid at room temperature for 3 hours. Thereafter, the substrate is sufficiently washed with ion exchange water, and then the substrate is immersed in the ion exchange water for one day.
Silane coupling treatment: The substrate is immersed in a stirred solution of 16 g of water, 4 g of acetic acid and 0.6 g of 3-aminopropyltrimethoxysilane at room temperature for 2 hours.
Developer: KOH: Potassium hydroxide TMAH: Tetrahydroammonium hydride MeOH: Methanol THF: Tetrahydrofuran DOX: Dioxane NMP: N-methylpyrrolidone The numbers represent mass ratios.
Development conditions; Immersion: Immersion in developer.
Ultrasonic treatment: The sample was immersed in a developer in an ultrasonic cleaner and irradiated with ultrasonic waves.

Example 9

1.0 g of isosorbide polycarbonate represented by the formula (8) is added to 9.0 g of DOX and dissolved by stirring with a stirrer at 50 ° C. for about 1 hour, and then a diazonaphthoquinone photosensitizer BADNQ3 as a photoacid generator. 0.20g was added, it stirred at room temperature for about 1 hour, and deaerated, and the photosensitive resin composition was prepared.

This solution was applied onto an electrolytic copper foil (matt surface) having a thickness of 35 μm by spin coating (700 rpm / 10 seconds + 900 rpm / 30 seconds), and pre-baked (90 ° C., 5 minutes) with a far-infrared hot air circulating dryer. Thereafter, a photosensitive polycarbonate coating film having a film thickness of about 3.1 μm was obtained.
This was irradiated with light in the i-line to g-line band through a positive photomask made of PET by an ultraviolet exposure machine (Oak). The exposure amount measured with an illuminometer for the i-line band was 400 mJ / cm ² .
After the exposure, the film was immersed in 20 g of a developer solution of 10% by mass potassium hydroxide methanol solution / DOX = 2/1 (mass ratio), developed at 40 ° C., and washed with 100 g of ion-exchanged water for 1 minute. As a result, a positive image was obtained. The development time at this time was 37 seconds. The resolution was 25 μm in a line and space pattern (Table 2). An SEM photograph of this photoresist is shown in FIG.

(Examples 10 to 14)
The same operations as in Example 9 were performed except that the substrate, substrate processing, developer composition, development temperature, development conditions, and development time were changed to the conditions shown in Table 2 (Table 2).

(Comparative Example 1)
When the same operation as in Example 1 was performed except that no photosensitizer was added, the coating film was completely dissolved and could not be patterned (Table 3).

  When the same operation as in Example 9 was carried out except that no photosensitizer was added, there was no difference in dissolution rate between the exposed / unexposed areas of the coating film, and patterning was not possible (Table 3).

(Reference Example 1)
Using a bisphenol-type polycarbonate (formula (9)) as the resin, light from the i-line to the g-line band is emitted by a UV exposure machine (Oak) through a PET positive photomask under the conditions in Table 3. Irradiation (exposure amount measured with illuminometer for i-line band was 400 mJ / cm ² ). As a result, a 25 μm line and space pattern was obtained (Table 4).

(Comparative Example 3)
The resin was bisphenol-type polycarbonate, and irradiated with an ArF excimer laser (wavelength: 193 nm, COMPexPro102 manufactured by Coherent Co., Ltd.) through a circular hole with a diameter of 5 mm under the conditions shown in Table 4 (exposure amount with a 193 nm illuminometer was 200 mJ) / Cm ² ). As a result, no difference was observed in the irradiated / unirradiated portions after development.

(Examples 15 to 16)
A cyclohexanedimethanol polycarbonate or isosorbide polycarbonate was used as the resin, and irradiated with an ArF excimer laser (wavelength 193 nm, COMPex Pro102 manufactured by Coherent Co., Ltd.) through a circular hole with a diameter of 5 mm under the conditions shown in Table 4 (in a 193 nm band illuminometer). The exposure amount is 200 mJ / cm ² ). As a result of washing the obtained photoresist layer with a developer, only the exposed area was dissolved in the developer, and a flood pattern was formed.

-Resin; CHDM-PC: Cyclohexanedimethanol polycarbonate ISB-PC: Isosorbide polycarbonate-Photosensitizer; BADNQ2 and BADNQ3: See formula (10) below-Substrate treatment;
Piranha treatment: The substrate is immersed in a stirred solution of 9 mL of 30% hydrogen peroxide and 21 mL of concentrated sulfuric acid at room temperature for 3 hours. Thereafter, the substrate is sufficiently washed with ion exchange water, and then the substrate is immersed in the ion exchange water for one day.
Silane coupling treatment: The substrate is immersed in a stirred solution of 16 g of water, 4 g of acetic acid and 0.6 g of 3-aminopropyltrimethoxysilane at room temperature for 2 hours.
Developer: KOH: Potassium hydroxide TMAH: Tetrahydroammonium hydride MeOH: Methanol THF: Tetrahydrofuran DOX: Dioxane NMP: N-methylpyrrolidone The numbers represent mass ratios.
Development conditions; Immersion: Immersion in developer.
Ultrasonic treatment: The sample was immersed in a developer in an ultrasonic cleaner and irradiated with ultrasonic waves.

From the above results, it was confirmed that in the photosensitive resin composition of each example using an alicyclic polycarbonate resin, good results can be obtained even if exposure is performed using various light beams having different wavelengths. It was. That is, even in Examples 1 to 14 using light in the i-line to g-line band (wavelength range of about 365 nm to 436 nm), a pattern with high resolution could be formed, and light with a low wavelength (193 nm) by an ArF excimer laser Also in Examples 15 and 16 using), it was confirmed that appropriate exposure of the photoresist layer was possible.
On the other hand, from the results of Reference Example 1 and Comparative Example 3, although the photosensitive resin composition using the aromatic polycarbonate resin can be appropriately used for exposure using light in the i-line to g-line band, It was confirmed that the photoresist layer cannot be exposed using light having a short wavelength (193 nm). Further, from the results of Reference Example 1 and Comparative Example 3, it can be said that resins other than the alicyclic polycarbonate resin of the formula (1) such as bisphenol-type polycarbonate can be used depending on the wavelength range of light used for exposure. It is also possible to use a polycarbonate resin other than the formula (1) in combination with the alicyclic polycarbonate resin of the formula (1).
In Comparative Examples 1 and 2, it was confirmed that an appropriate photosensitizer and developer are required for exposure.

Claims (11)

A photosensitive resin composition used for a reaction development image forming method, comprising an alicyclic polycarbonate resin having a structural unit represented by the formula (1), and a photosensitive agent.
(Wherein X is a C5-C20 cyclic aliphatic substituent having one or more ring structures not containing an aromatic ring, and the cyclic aliphatic substituent is a bridged structure and / or a spiro ring structure. Or a heteroatom,
R1 and R2 represent the same or different alkyl group having 1 to 4 carbon atoms, n1 and n2 represent the same or different integers of 0 to 2, and Z represents an oxygen atom or a single atom. Represents a bond. ) The photosensitive resin composition according to claim 1, wherein the cycloaliphatic substituent represented by X in the formula (1) is selected from the group consisting of the following (a-1) to (a-9). .
(N4 represents an integer of 0 to 3, n5 represents an integer of 1 to 6 which may be the same or different, n6 represents an integer of 0 to 1 which may be the same or different, and R3 represents 1 to 2 carbon atoms. R4 represents a methylene group or a single bond, and a broken line means a bond with an adjacent group.)   The photosensitive resin composition of Claim 1 or 2 in which the said photosensitive agent contains a quinonediazide compound. A reaction development image forming method comprising the following steps:
Process A: The process of forming a photoresist layer using the photosensitive resin composition as described in any one of Claims 1-3,
Step B: a step of exposing the photoresist layer using light or radiation, and step C: a step of developing the photoresist layer using a developer, a step of developing and developing, and then developing the reaction developed image. Law.   The reaction-developed image forming method according to claim 4, wherein the wavelength of the light or radiation is 248 nm or less.   The reaction development image forming method according to claim 4, wherein the light is irradiated by an ArF excimer laser.   The reaction development image forming method according to any one of claims 4 to 6, wherein the developer contains an alcohol compound or an ether compound.   The reactive development image forming method according to any one of claims 4 to 7, wherein the developer contains at least one selected from the group consisting of sodium hydroxide, potassium hydroxide, and tetramethylammonium hydroxide. .   100% by mass of the developer, alkali compound / alcohol compound / ether compound = 1 to 30% by mass / 20 to 90% by mass / 1 to 50% by mass, and the total value is 100% by mass. Item 9. The reactive development image forming method according to Item 7 or 8.   A semiconductor substrate, a liquid crystal substrate, or a printed wiring board manufactured using the reactive development image forming method according to any one of claims 4 to 9.   A structure having a diffraction grating, a lens material, or an optical waveguide including a finely shaped region formed by using the reactive development image forming method according to any one of claims 4 to 9.