Photoresist composition, method for forming a resist pattern, method for manufacturing a semiconductor device, and substrate processing apparatus.

Abstract

Disclosed is a photoresist composition containing a non-chemically amplified resist material and a sensitizer precursor. The sensitizer precursor is a compound for generating a sensitizer that absorbs non-ionizing radiation exceeding 300 nm, by irradiation with ionizing radiation or non-ionizing radiation having a wavelength of 300 nm or lower.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a photoresist composition, a method of forming a resist pattern, a method of manufacturing a semiconductor device, and a substrate processing apparatus.

Background Art

[0002] In order to form a fine resist pattern having a size of 20 nm, conventionally, a technique of extreme ultraviolet (EUV) lithography using a chemically amplified resist material has been widely applied. In the case of a chemically amplified resist material, generally, a reaction for forming a resist pattern proceeds by the action of an acid catalyst generated by pattern exposure. The influence of the diffusion of this acid catalyst may hinder further improvement in resolution.

[0003] On the other hand, in order to form a fine resist pattern, it has also been proposed to apply a non-chemically amplified resist material. For example, it has been reported that a cage compound containing tin oxide functions as a resist material by EUV irradiation (Patent Document 1 and Non-Patent Document 1). In addition, a main-chain cleavage type resist material having a main chain that is cleaved by EUV irradiation has also been proposed (Patent Documents 2, 3, and 4). The non-chemically amplified resist material is expected to be more advantageous than the chemically amplified resist material for forming a resist pattern with higher resolution in that it is less affected by the diffusion of an acid catalyst.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0005] [Non-Patent Document 1] J. Micro / Nanolith. MEMS MOEMS 16(2), 023510 (Apr-Jun 2017) [Overview of the project] [Problems that the invention aims to solve]

[0006] When forming a resist pattern using a photoresist composition containing a non-chemically amplified resist material, further improvements are desired in terms of improving sensitivity and reducing the roughness of the resist pattern. [Means for solving the problem]

[0007] A photoresist composition relating to one aspect of this disclosure comprises a non-chemically amplified resist material and a sensitizer precursor. The sensitizer precursor is a compound that, upon irradiation with a first radiation, generates a sensitizer that absorbs a second radiation having a wavelength longer than the wavelength of the first radiation.

[0008] Using the above photoresist composition, a resist film containing a non-chemically amplified resist material and a sensitizer precursor can be formed. When a portion of the resist film is irradiated with a first radiation, a sensitizer is generated from the sensitizer precursor in the portion of the resist film irradiated with the first radiation. Subsequently, when a second radiation is irradiated all at once, the reaction of the non-chemically amplified resist material proceeds, and this reaction is accelerated by the sensitizer. At the stage of irradiation with the first radiation, it is sufficient for the sensitizer to be generated, and it is not necessary for the reaction of the non-chemically amplified resist material to proceed. Therefore, even if the dose of the first radiation is small, the reaction of the non-chemically amplified resist material can proceed sufficiently by irradiation with the second radiation. That is, a resist pattern can be formed with higher sensitivity. Although irradiation with the second radiation is necessary, the reduction in the dose of the first radiation, which requires higher energy, is advantageous for the overall process. In addition, according to the inventors' findings, the roughness of the formed resist pattern is also reduced. [Effects of the Invention]

[0009] According to the photoresist composition of this disclosure, when forming a resist pattern using a photoresist composition containing a non-chemically amplified resist material, further improvements can be made in terms of improving sensitivity and reducing the roughness of the resist pattern. [Brief explanation of the drawing]

[0010] [Figure 1] This flowchart shows an example of a method for forming a resist pattern. [Figure 2] This is a process diagram illustrating an example of a method for manufacturing a semiconductor device, which includes forming a resist pattern. [Figure 3] This is a process diagram illustrating an example of a method for manufacturing a semiconductor device, which includes forming a resist pattern. [Figure 4] This is a process diagram illustrating an example of a method for manufacturing a semiconductor device, which includes forming a resist pattern. [Figure 5]This flowchart shows an example of a method for forming a resist pattern. [Figure 6] This flowchart shows an example of a method for forming a resist pattern. [Figure 7] This is a schematic diagram showing an example of a substrate processing device. [Figure 8] This is a schematic diagram showing an example of a substrate processing device. [Figure 9] This graph shows the relationship between the thickness of the resist film and the dose of the KrF excimer laser. [Figure 10] This graph shows the relationship between line width (CD) and EUV irradiation dose (relative value). [Figure 11] This graph shows the relationship between line width (CD) and EUV irradiation dose (relative value). [Figure 12] This graph shows the relationship between the rate of increase in CD and the amount of UV exposure. [Modes for carrying out the invention]

[0011] The embodiments described herein are illustrated below to illustrate the present invention. However, the present invention should not be limited to the following. In the following description, the same reference numerals are used for the same elements or elements having the same function, and redundant descriptions may be omitted.

[0012] Figure 1 is a flowchart showing an example of a method for forming a resist pattern. Figures 2, 3, and 4 are process diagrams showing an example of a method for forming a resist pattern and a method for manufacturing a semiconductor device that includes forming a resist pattern by that method.

[0013] The method for forming the resist pattern shown in Figures 1-4 includes, in this order: a step S10 of applying a photoresist composition onto a film to be etched 3 provided on a semiconductor wafer 1; a step S11 of forming a resist film 5 by baking the applied photoresist composition; a pattern exposure step S20 of irradiating a part (5E) of the resist film 5 with a first radiation R1; a batch exposure step S30 of irradiating the entire region of the resist film 5, including the part 5E irradiated with the first radiation R1 and the remaining part, with a second radiation R2 having a wavelength longer than the wavelength of the first radiation R1; a step S31 of baking the resist film 5 after batch exposure; and a step S40 of removing a part of the resist film 5 by contact with a developer, thereby forming a resist pattern 5A having trenches 5a that expose the film to be etched 3. Figures 2-4 show an example of the process when the resist film 5 is a negative-type resist. The first radiation R1 is ionizing radiation or non-ionizing radiation, and the second radiation R2 is non-ionizing radiation. When the first radiation R1 is non-ionizing radiation, the second radiation R2 is non-ionizing radiation with a longer wavelength than the first radiation.

[0014] The photoresist composition used to form the resist film 5 comprises a non-chemically amplified resist material and a sensitizer precursor. The sensitizer precursor is a compound that generates a sensitizer that absorbs a second radiation R2 upon irradiation with a first radiation R1.

[0015] Non-chemically amplified resist materials are understood by those skilled in the art as resist materials other than chemically amplified resist materials, and are resist materials whose solubility in a developer can be changed by irradiation with radiation without the generation of an acid catalyst. Examples of non-chemically amplified resist materials include metal oxide photoresist materials and main-chain cleavage resist materials.

[0016] The metal oxide photoresist material may include, for example, a metal oxide containing metal atoms and an organometallic compound containing an organic ligand bonded to the metal atoms. The metal oxide photoresist material may also be nanoparticles (particles with a maximum width of less than 1 μm). The metal oxide may be a cage-like compound. The metal oxide photoresist material containing the organometallic compound is thought to form a crosslinked structure through a reaction that includes the detachment of the organic ligand from the metal atoms by irradiation with radiation (particularly the second radiation R2), and the bonding of the metal atoms from which the organic ligand has detached via oxygen atoms, etc., through a condensation reaction. Hydroxyl groups are generated by the detachment of the organic ligand, and a crosslinked structure can be formed by a condensation reaction between the hydroxyl groups. The condensation reaction can be promoted by baking the resist film 5 after simultaneous exposure to the second radiation R2. Since the formed crosslinked structure is substantially insoluble in the developer, the metal oxide photoresist material can function as a negative-type resist material. When the metal oxide photoresist material is nanoparticles, multiple nanoparticles may link together to form aggregates that are substantially insoluble in the developer. The sensitizer produced from the sensitizer precursor, upon absorbing a second radiation R2, primarily promotes a reaction in which an organic ligand is eliminated to form a hydroxyl group, and a condensation reaction in which the metal atoms from which the organic ligand has been eliminated bond together.

[0017] Metal oxide photoresist materials, after the hydroxyl group is generated by the detachment of organic ligands and before the condensation reaction proceeds significantly, can exhibit high solubility in alkaline developers. On the other hand, the resist film in the portion not irradiated with the first radiation R1, where most of the organic ligands and sensitizer precursors remain, is usually substantially insoluble in alkaline developers. This property can be utilized to make metal oxide photoresist materials function as positive-type resist materials. As a positive-type resist material, metal oxide photoresist materials function based on a similar mechanism to metal oxide photoresist materials as negative-type resist materials, in that it involves the generation of a sensitizer by irradiation with the first radiation R1 and the detachment of organic ligands by irradiation with the second radiation R2 in the presence of the sensitizer. Therefore, metal oxide photoresist materials as positive-type resist materials can also be further improved in terms of increased sensitivity and reduced roughness of the resist pattern.

[0018] The metal oxide in the metal oxide photoresist material may include at least one metal atom selected from the group consisting of, for example, Sn, Sb, In, Ti, Zr, Hf, V, Co, Mo, W, Al, Ga, Si, Ge, P, As, Y, La, Ce, and Lu. The organic ligand bonded to the metal atom of the metal oxide may be, for example, a branched or unbranched alkyl group which may have substituents, or a cycloalkyl group which may have substituents. The alkyl group and cycloalkyl group may bond to the metal atom at a primary, secondary, or tertiary carbon atom. The number of carbon atoms in the alkyl group and cycloalkyl group may be 1 to 30. Examples of alkyl groups as organic ligands include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, and n-octyl group. Examples of cycloalkyl groups as organic ligands include cyclobutyl group, cyclopropyl group, cyclohexyl group, 1-adamantyl group, and 2-adamantyl group. Examples of substituents that alkyl groups and cycloalkyl groups may have include cyano groups, alkylthio groups, silyl groups, alkyloxy groups, alkylcarbonyl groups, alkylcarboniloyl groups, and halogeno groups. Nanoparticles containing cage-like tin oxides and organic ligands are, for example, of the formula:[(SnR) 12 O 14 The compound can be represented as (OH)6](OH)2 (where R represents an organic ligand).

[0019] A main-chain severing resist material is a polymer material having a main chain that is severed by irradiation with a second radiation R2 in the presence of a sensitizer produced from a sensitizer precursor, and typically functions as a positive-type resist. The main-chain severing resist material may be, for example, a copolymer containing α-alkylstyrene units and α-alkyl haloacrylate units. This copolymer may also be a copolymer containing α-methylstyrene units and α-methyl chloroacrylate units.

[0020] The sensitizer precursor may be, for example, a compound that generates a sensitizer having a carbonyl group, and examples thereof include acetal compounds, ketal compounds, thioacetal compounds, alcohol compounds, thiol compounds, and orthoester compounds.

[0021] The acetal compounds, ketal compounds, and thioacetal compounds that can be used as the sensitizer precursor may be, for example, compounds represented by the following formula (1), which are converted into a ketone compound represented by the formula (1A) by irradiation with the first radiation R1.

[0022] [Chemical formula]

[0023] In formulas (1) and (1A), Z 1 represents an oxygen atom or a sulfur atom. In formulas (1) and (1A), R 1 represents an aryl group that may have a substituent (for example, a phenyl group, a naphthyl group, or an anthracenyl group), or a conjugated diene group that may have a substituent. In formulas (1) and (1A), R 2 represents a hydrogen atom, a halogen atom, an aryl group that may have a substituent (for example, a phenyl group, a naphthyl group, or an anthracenyl group), a conjugated diene group that may have a substituent, a hydrocarbon group having 1 to 30 or 1 to 5 carbon atoms that may have a substituent (for example, an alkyl group), an alkanoyl group having an alkyl group having 1 to 12 carbon atoms that may have a substituent, an amino group, or an aminocarbonyl group. In formulas (1) and (1A), R 3 and R 4 each independently represent a hydrocarbon group having 1 to 30 or 1 to 5 carbon atoms that may have a substituent (for example, an alkyl group). R 1 and R 2 may be bonded to each other directly or via a divalent group to form a cyclic structure. R 3 and R 4 may be bonded to each other directly or via a divalent group to form a cyclic structure.

[0024] R1 ~R 4 Examples of divalent groups that constitute the cyclic structure formed by these groups are -CH2-, -O-, -S-, -SO2-, -SO2NH-, -C(=O)-, -C(=O)O-, -NHCO-, -NHC(=O)NH-, -CHR A -, -CR A 2-, -NH-, and -NR A -Includes R A R represents a phenyl group, a phenoxy group, or a halogen atom. A The phenyl and phenoxy groups may be substituted with hydrocarbon groups having 1 to 30 or 1 to 5 carbon atoms (e.g., alkyl groups), hydroxyl groups, or alkyl groups having 1 to 5 carbon atoms.

[0025] R 1 or R 2 Examples of substituents that aryl groups and non-conjugated diene groups may have include C1-C30 or C1-C5 hydrocarbon groups (e.g., alkyl groups), C1-C5 hydroxyalkoxy groups, C1-C5 hydroxyalkyl groups, C1-C5 alkoxy groups which may have substituents, amino groups, aminocarbonyl groups, and hydroxyl groups. 1 ~R 4 Examples of substituents that hydrocarbon groups, alkanoyl groups, and alkoxy groups may have include alkoxy groups having 1 to 5 carbon atoms, alkoxycarbonyl groups having an alkyl group having 1 to 5 carbon atoms, cycloalkoxycarbonyl groups having a cycloalkyl group having 5 to 30 carbon atoms, furyl groups, phenoxy groups, naphthoxy groups, anthracenoxy groups, amino groups, aminocarbonyl groups, and hydroxyl groups.

[0026] R 3 and R 4Acetal compounds in which alkyl groups are directly bonded to each other can be represented by the following formulas, for example. In these formulas, substituents such as C1-C5 alkyl groups, C3-C30 cycloalkyl groups, C1-C5 alkoxy groups, alkoxycarbonyl groups having C1-C5 alkyl groups, cycloalkoxycarbonyl groups having C5-C30 cycloalkyl groups, furyl groups, phenoxy groups, naphthoxy groups, anthracenoxy groups, amino groups, aminocarbonyl groups, and hydroxyl groups may be bonded to the carbon atoms constituting the cyclic structure.

[0027] [ka]

[0028] Alcohol compounds and thiol compounds that can be used as sensitizer precursors may be, for example, compounds represented by formula (2) below, which are converted to ketone compounds represented by formula (2A) by irradiation with the first radiation R1.

[0029] [ka]

[0030] In equations (2) and (2A), Z 1 R represents an oxygen atom or a sulfur atom. In formulas (2) and (2A), R 5 R represents an optionally substituted aryl group (e.g., a phenyl group, a naphthyl group, or an anthracenyl group) or an optionally substituted conjugated diene group. In formulas (2) and (2A), R 6 R represents an optionally substituted aryl group (e.g., phenyl, naphthyl, or anthracenyl group), an optionally substituted conjugated diene group, an optionally substituted C1-C30 or C1-C5 hydrocarbon group (e.g., alkyl group), an optionally substituted C1-C12 alkyl group alkanoyl group, amino group, or aminocarbonyl group. In formulas (2) and (2A), R 7 R represents a hydrogen atom or a halogen atom. In formulas (2) and (2A), R8 R represents a hydrogen atom. 5 and R 6 These may be bonded to each other directly or via divalent groups to form a cyclic structure. 5 or R 6 The aryl group and non-conjugated diene group as R 1 or R 2 The aryl group and conjugated diene group may have substituents similar to those that the aryl group and conjugated diene group may have. 5 and R 6 The divalent groups that constitute the cyclic structure formed by are R 1 ~R 4 It can be a group similar to the divalent group that constitutes the cyclic structure formed by it.

[0031] The orthoester compounds that can be used as sensitizer precursors may be, for example, compounds represented by formula (3) or (4) below, which are converted to the ester compound represented by formula (3A) or the carboxylic acid compound represented by formula (4A), respectively, by irradiation with the first radiation.

[0032] [ka]

[0033] In equations (3) and (4), R 9 R represents an aryl group which may have substituents (e.g., a phenyl group, a naphthyl group, or an anthracenyl group). In formulas (3) and (4), R 10 R represents a hydrocarbon group (e.g., alkyl group) having 1 to 30 or 1 to 5 carbon atoms, which may have substituents. Multiple R in the same molecule 10 They may be the same or different. 9Examples of substituents that an aryl group may have include C1-C30 or C1-C5 alkyl groups, aryloxy groups, arylalkyl groups having C1-C5 alkyl groups, arylalkyloxy groups having C1-C5 alkyl groups, C1-C5 hydroxyalkoxy groups, C1-C5 hydroxyalkyl groups, C1-C5 alkoxy groups, amino groups, aminocarbonyl groups, and hydroxyl groups. 9 The aryl group may contain two or more aromatic rings that are directly or via divalent groups bonded to each other at two or more locations. 11 R represents a hydrogen atom, a C1-C30 or C1-C5 hydrocarbon group which may have substituents (e.g., alkyl group), a C1-C5 aryl group which may have substituents (e.g., phenyl group, naphthyl group, or anthracenyl group), a C1-C5 alkoxy group which may have substituents, or a C1-C5 aryloxy group which may have substituents (e.g., phenoxy group, naphthoxy group, or anthracenoxy group). 11 Examples of substituents that hydrocarbon groups, aryl groups, alkoxy groups, and aryloxy groups may have include alkoxy groups having 1 to 5 carbon atoms, alkoxycarbonyl groups having an alkyl group having 1 to 5 carbon atoms, cycloalkoxycarbonyl groups having a cycloalkyl group having 5 to 30 carbon atoms, furyl groups, phenoxy groups, naphthoxy groups, anthracenoxy groups, amino groups, aminocarbonyl groups, and hydroxyl groups.

[0034] More specific examples of ketal compounds that can be used as sensitizer precursors include compounds represented by the following formulas (11) or (12).

[0035] [ka]

[0036] In equations (11) and (12), R 3 and R 4 R in equation (1) 3 and R 4 Defined similarly, R 12 and R 13Each of these independently represents a hydrocarbon group having 1 to 30 or 1 to 5 carbon atoms (e.g., an alkyl group), a hydroxyalkoxy group having 1 to 5 carbon atoms, a hydroxyalkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms which may have substituents, an amino group, an aminocarbonyl group, or a hydroxyl group, and two R 12 or R 13 These may form a cyclic structure by being directly linked to each other or via divalent groups. m and n each independently represent integers from 0 to 4, and multiple R groups in the same molecule 12 and R 13 These may be the same or different. In equation (11), Z 2 -O-, -S- and -NR A - Indicates a divalent group selected from. A The above-mentioned R A It is a similar group to R. 12 or R 13 Examples of substituents that an alkoxy group may have include alkyl groups having 1 to 5 carbon atoms.

[0037] R 12 and R 13 The R may be a hydroxyalkoxy group having 1 to 5 carbon atoms, and two R 12 or two R 13 When these are combined, they form the following equation: [ka] A group represented by R may be formed. 14 R represents an alkyl group having 1 to 5 carbon atoms. An example of an acetal compound in this case is represented by the following formula (11a) or (11b). In formula (11a), R 15 and R 16 This represents an alkyl group having 1 to 5 carbon atoms, or a hydroxyalkyl group having 1 to 5 carbon atoms.

[0038] [ka]

[0039] The amount of sensitizer precursor in the photoresist composition or the pre-exposure resist film 5 formed therefrom is adjusted so as to sufficiently promote the reaction of the non-chemically amplified resist material by irradiation with a second radiation. For example, the amount of sensitizer precursor may be 0.1 to 40 parts by mass, or 1 to 20 parts by mass, per 100 parts by mass of the non-chemically amplified resist material.

[0040] The photoresist composition may contain a solvent. The solvent is selected from those capable of dispersing or dissolving the non-chemically amplified resist material and the sensitizer precursor. Examples of solvents include ketones such as cyclohexanone and methyl-2-amyl ketone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; and esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol monomethyl ether acetate, and propylene glycol monotert-butyl ether acetate.

[0041] The amount of solvent in the photoresist composition is adjusted within a range that allows for the proper formation of the resist film 5 by methods such as spin coating. For example, the amount of solvent may be 500 to 100,000 parts by mass per 100 parts by mass of non-chemically amplified resist material.

[0042] The photoresist composition is applied to the film to be etched 3, for example, by spin coating (step S11). The solvent in the photoresist composition is removed by baking the applied photoresist composition (step S20). A pre-formed resist film 5 may be laminated on the film to be etched 3. The thickness of the resist film 5 may be, for example, 1 to 5000 nm, 10 to 1000 nm, or 30 to 200 nm.

[0043] A resist film 5 may be formed using a photoresist composition that includes a non-chemically amplified resist material and a sensitizer precursor, and is substantially solvent-free. In this case, for example, the resist film 5 is formed by depositing the photoresist composition on a workpiece having the film to be etched 3 by a deposition method such as atomic layer deposition (ALD) or chemical vapor deposition (CVD).

[0044] The formed resist film 5 is irradiated with a first radiation R1 through a mask 7 having openings placed on the resist film 5 (step S20). As a result, the portion of the resist film 5 exposed within the openings of the mask 7 (5E) is irradiated with the first radiation R1 having a pattern corresponding to the openings. In the portion 5E irradiated with the first radiation R1, a sensitizer is generated from the sensitizer precursor.

[0045] The first radiation R1 may be ionizing radiation or non-ionizing radiation with a wavelength of 300 nm or less. The light source for the first radiation R1 may be, for example, an electron beam from 1 keV to 200 keV, extreme ultraviolet (EUV) light with a wavelength of 13.5 nm, excimer laser light of 193 nm (ArF excimer laser light), or excimer laser light of 248 nm (KrF excimer laser light). The dose of the first radiation may be, for example, 100 to 200 mJ / cm². 2 This may also be the case. Exposure with the first radiation R1 can be performed by immersion lithography or dry lithography. Instead of using a mask, the first radiation R1 may be irradiated along a predetermined pattern.

[0046] After irradiation with the first radiation R1, the mask 7 is removed, and then the second radiation R2 is irradiated simultaneously onto the entire region of the resist film 5, including the portion 5E irradiated with the first radiation R1 and the remaining portion (step S30, simultaneous exposure). When the second radiation R2 is irradiated, the non-chemically amplified resist material reaction proceeds in the portion 5E irradiated with the first radiation R1 in the presence of a sensitizer, thereby selectively changing the solubility of that portion 5E in the developer. The time from the end of irradiation with the first radiation R1 to the start of irradiation with the second radiation R2 may be 4 to 120 seconds.

[0047] The second radiation, R2, is non-ionizing radiation. If the first radiation, R1, is ionizing radiation, then the second radiation, R2, has a longer wavelength than the first radiation, R1. For example, the second radiation, R2, may be non-ionizing radiation with a wavelength exceeding 300 nm (e.g., ultraviolet radiation). The light source for the second radiation, R2, may be, for example, a mercury lamp, a xenon lamp, or an LED. The dose of the second radiation is, for example, 0.01 to 10 J / cm². 2 This may also be the case. The exposure with the second radiation R2 can be performed by immersion lithography or dry lithography.

[0048] After a single exposure with a second radiation dose R2, the resist film 5 is baked (step S31). Baking after exposure can further reduce the roughness of the formed resist pattern 5A. Heating for baking after exposure can be carried out in air or in an inert gas atmosphere such as nitrogen and argon. The heating temperature may be 50 to 200°C, and the heating time may be 10 to 300 seconds.

[0049] Next, a portion of the resist film 5 is removed by development, thereby forming a resist pattern 5A having trenches 5a that expose the film to be etched 3 (step S40, Figure 4(a)). If the resist film 5 is a negative-type resist, the portion 5E irradiated with the first radiation R1 remains as the resist pattern 5A without substantially dissolving in the developer. If the resist film 5 is a positive-type resist, contrary to the illustrated embodiment, the portion 5E irradiated with the first radiation R1 is removed, and the remaining portion remains as the resist pattern 5A.

[0050] The development of the resist film 5 may include removing a portion of the resist film 5 by contact with a developer. The developer is selected from those that efficiently dissolve the portion 5E irradiated with the first radiation R1 or the remaining portion, and can be, for example, an organic developer or an alkaline developer.

[0051] When the non-chemically amplified resist material is a metal oxide photoresist material, the developer may be an organic developer or an alkaline developer. When a resist film containing a metal oxide photoresist material is used as a negative-type resist, an organic developer is usually used. When a resist film containing a metal oxide photoresist material is used as a positive-type resist, an alkaline developer is usually used.

[0052] Organic developers used for developing resist films containing metal oxide photoresist materials include, for example, ketones, alcohols, esters, organic acids, or combinations thereof. Examples of ketones include 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, and methylacetophenone. Examples of alcohols include methyl isobutylcarbinol (MIBC), methyl alcohol, ethyl alcohol, isopropyl alcohol, and butanol. Examples of esters include propylene glycol monomethyl ether acetate (PGMEA), heptyl acetate, 1-methylheptyl acetate, octyl acetate, 1-methyloctyl acetate, nonyl acetate, decyl acetate, undecyl acetate, dodecyl acetate, tetradecyl acetate, pentadecyl acetate, hexadecyl acetate, heptadecyl acetate, octadecyl acetate, nonadecyl acetate, eicosyl acetate, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate, and ethyl butyrate. Examples of organic acids include acetic acid and butyric acid.

[0053] The alkaline developer used for developing a resist film containing a metal oxide photoresist material may be a solution (e.g., an aqueous solution) containing one or more alkaline compounds selected from, for example, tetraalkylammonium hydroxide, choline, alkali metal hydroxides, alkali metal metasilicates or their hydrates, alkali metal phosphates or their hydrates, ammonia, alkylamines, alkanolamines, and heterocyclic amines. The alkaline developer may also be an aqueous solution of tetramethylammonium hydroxide. The alkaline developer may optionally contain additional components selected from methanol, water-soluble organic solvents such as ethanol, and surfactants. After development with the alkaline developer, rinsing with a rinse solution such as water and an organic solution may be performed.

[0054] If the non-chemically amplified resist material is a main-chain cleavage resist material, the developer may be an organic developer. The organic developer may include, for example, ketones, alcohols, esters, or combinations thereof. Examples of ketones include 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, and methylacetophenone. Examples of alcohols include methyl isobutylcarbinol (MIBC), methyl alcohol, ethyl alcohol, isopropyl alcohol, and butanol. Examples of esters include propylene glycol monomethyl ether acetate (PGMEA), heptyl acetate, 1-methylheptyl acetate, octyl acetate, 1-methyloctyl acetate, nonyl acetate, decyl acetate, undecyl acetate, dodecyl acetate, tetradecyl acetate, pentadecyl acetate, hexadecyl acetate, heptadecyl acetate, octadecyl acetate, nonadecyl acetate, eicosyl acetate, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, and isoamyl acetate.

[0055] The development of the resist film 5 may include removing a portion of the resist film 5 by dry development. Dry development may be, for example, plasma etching or chemical etching.

[0056] Figures 5 and 6 are flowcharts showing another example of a method for forming a resist pattern.

[0057] The method shown in Figure 5 further includes a step S21 in which the resist film is baked after the first radiation pattern exposure (step S20) and before the second radiation batch exposure (step S30). The addition of the first bake after pattern exposure (step S21) can further reduce the roughness of the formed resist pattern 5A. The heating conditions for the first bake after pattern exposure (step S21) can be the same as the heating conditions exemplified for the bake after batch exposure (step S31). Alternatively, the bake after pattern exposure (step S21) may be introduced and the bake after batch exposure may be omitted, as in the method shown in Figure 6.

[0058] A method for manufacturing a semiconductor device further includes the step of etching the film to be etched 3 exposed in the trenches 5a of the resist pattern 5A, as shown in Figures 4(f) and 4(g), thereby forming a patterned film to be etched 3A such that trenches 3a are formed. The method for etching the film to be etched 3 can be selected considering the type of material constituting the film to be etched 3, and may be, for example, dry etching or wet etching. After etching, the resist pattern 5A may be removed. A semiconductor wafer 1 and a processed substrate 10 having the patterned film to be etched 3A are obtained by the method illustrated in Figure 4.

[0059] The patterned etched film 3A may be, for example, an active layer, a lower insulating film, a gate electrode film, or an upper insulating film. Wiring may be embedded in the trenches 3a of the etched film 3A. By the method according to this disclosure, for example, a semiconductor device including a semiconductor substrate and an integrated circuit including the patterned etched film formed on the semiconductor substrate can be manufactured.

[0060] A resist pattern formed by the method described herein can also be used as a mask for etching to produce a lithography mask or a nanoimprint template. The lithography mask may be a transmissive mask or a reflective mask.

[0061] For the methods illustrated above, for example, a substrate processing apparatus can be used that mainly comprises: a film forming unit that forms a resist film containing a non-chemically amplified resist material and a sensitizer precursor on a workpiece having a film to be etched; an exposure unit that irradiates the resist film having a portion irradiated with a first radiation with a second radiation; a developing unit that removes a portion of the resist film by contact with a developer solution, thereby forming a resist pattern; and a control unit that controls the exposure unit so that the second radiation is irradiated collectively to the entire region of the resist film including the portion irradiated with the first radiation and the remaining portion. The film forming unit may also include a coating unit that coats a photoresist composition onto a workpiece having a film to be etched, and a heat treatment unit that bakes the coated photoresist composition to form a resist film on the film to be etched.

[0062] Figures 7 and 8 are schematic diagrams showing an example of a substrate processing apparatus. Figure 7 also shows an example of an exposure apparatus used in combination with the substrate processing apparatus. Figure 8 shows an example of the internal configuration of the substrate processing apparatus 20 shown in Figure 7. The substrate processing apparatus 20 shown in Figures 7 and 8 comprises a carrier block 24, a processing block 25, and an interface block 26. The workpiece W is processed by the substrate processing apparatus 20 in the manner described above.

[0063] The carrier block 24 is configured to introduce the workpiece W into the substrate processing apparatus 20 and to bring the workpiece W out of the substrate processing apparatus 20. The carrier block 4 has a transport device A1 that includes a transfer arm. The transport device A1 takes the workpiece W housed in the carrier C and passes it to the processing block 25, and receives the workpiece W from the processing block 25 and returns it to the carrier C.

[0064] The processing block 25 has processing modules 11, 12, 13, and 14, which are stacked in this order. Each of the processing modules 11, 12, 13, and 14 contains multiple processing units U1, U2 and a transport device A3 for transporting workpieces W to these processing units.

[0065] The processing module 11 may be configured to form an underlying film (etchable film) on the surface of a substrate (e.g., a semiconductor wafer) as a workpiece W. In the processing module 11, for example, processing unit U1 may be a liquid processing unit that applies a coating liquid for forming the underlying film to the workpiece W, and processing unit U2 may be a heat processing unit that heat-treats the applied coating liquid to form the underlying film.

[0066] The processing module 12 may be configured to form a resist film on the underlying film (etched film) of the workpiece W. In the processing module 12, for example, processing unit U1 may be a coating unit that coats the photoresist composition onto the workpiece W, and processing unit U2 may be a heat treatment unit that bakes the coated photoresist composition to form a resist film. In that case, the coating unit and the heat treatment unit constitute a film formation unit that forms a film of the photoresist composition. The workpiece W having the resist film is transported to the exposure apparatus 30 via the interface block 26, where a portion of the resist film may be irradiated with first radiation. A film formation unit that deposits the photoresist composition onto the workpiece W to form a resist film may be provided instead of, or in addition to, the coating unit.

[0067] The processing module 13 may be configured to irradiate the resist film having a portion irradiated with the first radiation in the exposure apparatus 30 with a second radiation. In the processing module 13, for example, processing unit U1 may be an exposure unit having a light source for the second radiation, and processing unit U2 may be a heat treatment unit for baking the resist film before or after irradiation with the second radiation.

[0068] The processing module 14 may be configured to function as a developing unit that removes a portion of the resist film irradiated with the second radiation by contact with a developer solution, thereby forming a resist pattern. In the processing module 14, for example, processing unit U1 may be a liquid processing unit that supplies a developer solution and, if necessary, a rinsing solution to the resist film, and processing unit U2 may be a heat processing unit for heat treatment of the resist film before and after development. The processing module 14 may also be configured to function as a developing unit that removes a portion of the resist film irradiated with the second radiation by dry development, thereby forming a resist pattern.

[0069] The processing block 25 further includes a shelf unit U10 provided on the carrier block 24 side. The shelf unit U10 is divided into multiple cells arranged in the vertical direction. A transport device A7 including a lifting arm is provided near the shelf unit U10. The transport device A7 lifts and lowers the workpiece W between the cells of the shelf unit U10. The processing block 25 also includes a shelf unit U11 provided on the interface block 26 side. The shelf unit U11 is divided into multiple cells arranged in the vertical direction.

[0070] The interface block 26 is configured to transfer workpieces W between the processing block 25 and the exposure device 30. The interface block 26 incorporates a transport device A8 (transport unit) including a transfer arm. The transport device A8 transfers the workpieces W placed on the shelf unit U11 to the exposure device 30. The transport device A8 receives the workpieces W from the exposure device 30 and returns them to the shelf unit U11.

[0071] The control device 100 (control unit) controls the units constituting each block so that the desired resist pattern is formed on the workpiece W. For example, the control device 100 controls the exposure unit (e.g., processing unit U1 in the processing module) so that the second radiation is irradiated all at once to the entire region of the resist film, including the portion irradiated by the first radiation and the remaining portion. The control device 100 can also control the transport unit (transport device A8) of the interface block 26 so that the workpiece having the resist film irradiated by the first radiation is transported to the exposure unit in the exposure apparatus 30.

[0072] The specific configuration of the substrate processing apparatus is not limited to the configuration of the substrate processing apparatus 20 exemplified above. For example, an exposure unit may be provided between the processing block and the interface block to irradiate a resist film having a portion irradiated with a first radiation with a second radiation.

[0073] Exemplary embodiments included in this disclosure are described below. [E1] Non-chemically amplified resist materials, Sensitizer precursor and Includes, A photoresist composition in which the sensitizer precursor is a compound that generates a sensitizer that absorbs non-ionizing radiation having a wavelength greater than 300 nm when irradiated with ionizing radiation or non-ionizing radiation having a wavelength of 300 nm or less. [E2] The photoresist composition according to [E1], wherein the non-chemically amplified resist material is a metal oxide photoresist material. [E3] The photoresist composition according to [E1], wherein the non-chemically amplified resist material is a main-chain cleavage resist material. [E4] The photoresist composition according to any one of [E1] to [E3], wherein the sensitizer precursor comprises at least one compound selected from the group consisting of acetal compounds, ketal compounds, thioacetal compounds, alcohol compounds, thiol compounds, and orthoester compounds, which generates the sensitizer having a carbonyl group. [E5] Photoresist composition according to any one of [E1] to [E4], further comprising a solvent. [E6] Irradiating a portion of a resist film containing a non-chemically amplified resist material and a sensitizer precursor with a first radiation, The second radiation is irradiated collectively to the entire region of the resist film, including the portion irradiated with the first radiation and the remaining portion. A portion of the resist film is removed by development, thereby forming a resist pattern. This includes them in this order, When the first radiation is ionizing radiation or non-ionizing radiation, and the second radiation is non-ionizing radiation, and the first radiation is non-ionizing radiation, the second radiation is non-ionizing radiation having a wavelength longer than the wavelength of the first radiation. The sensitizer precursor is a compound that generates a sensitizer that absorbs the second radiation upon irradiation with the first radiation. A method for forming a resist pattern. [E7] The method according to [E6], wherein the non-chemically amplified resist material is a metal oxide photoresist material. [E8] The method according to [E6], wherein the non-chemically amplified resist material is a main-chain cleavage resist material. [E9] The method according to any one of [E6] to [E8], wherein the sensitizer precursor comprises at least one compound selected from the group consisting of acetal compounds, ketal compounds, thioacetal compounds, alcohol compounds, thiol compounds, and orthoester compounds, which causes the sensitizer having a carbonyl group to produce the sensitizer. [E10] The first radiation is ionizing radiation or non-ionizing radiation having a wavelength of 300 nm or less. The second radiation is non-ionizing radiation having a wavelength greater than 300 nm. The method described in any one of the items [E6] to [E9]. [E11] The method according to any one of [E6] to [E10], further comprising baking the resist film between the irradiation of the first radiation and the irradiation of the second radiation, after the irradiation of the second radiation, or both thereof. [E12] A method for manufacturing a semiconductor device having a patterned film, wherein the method is A resist pattern having trenches in which the etched film is exposed is formed on the etched film by the method described in any one of the items [E6] to [E11], Etching the film to be etched exposed in the trench, thereby patterning the film to be etched, Methods that include... [E13] A film forming unit that forms a resist film containing a non-chemically amplified resist material and a sensitizer precursor on a workpiece having a film to be etched, An exposure unit that irradiates the resist film having a portion irradiated with a first radiation with a second radiation, A developing unit that removes a portion of the resist film by developing, thereby forming a resist pattern, A control unit controls the exposure unit such that the second radiation is irradiated simultaneously over the entire region of the resist film, including the portion irradiated by the first radiation and the remaining portion. Equipped with, The first radiation is ionizing radiation or non-ionizing radiation, the second radiation is non-ionizing radiation, and when the first radiation is non-ionizing radiation, the second radiation is non-ionizing radiation having a wavelength longer than the wavelength of the first radiation. Circuit board processing equipment. [E14] The substrate processing apparatus, A processing block including the film forming unit, the exposure unit, and the developing unit, An interface block including a transfer unit for transferring a workpiece having the resist film between the processing block and the exposure apparatus that irradiates a portion of the resist film with the first radiation, Equipped with, The substrate processing apparatus according to [E13], wherein the control unit controls the transport unit so that the workpiece having the resist film irradiated with the first radiation is transported to the exposure unit in the exposure apparatus. [E15] The substrate processing apparatus according to [E13] or [E14], wherein the film forming unit includes a coating unit that coats a photoresist composition comprising the non-chemically amplified resist material and the sensitizer precursor onto the workpiece. [E16] The substrate processing apparatus according to [E15], wherein the film forming unit further comprises a heat treatment unit that bakes the film of the applied photoresist composition to form a resist film containing the non-chemically amplified resist material and the sensitizer precursor on the film to be etched. [Examples]

[0074] The present disclosure will be described in more detail below with reference to examples. However, the present invention is not limited to these examples.

[0075] (Preparation of photoresist composition) Photoresist composition 1 As a non-chemically amplified resist material, a cage-like tin oxide compound and nanoparticles having an organic ligand ([(SnR) 12 O 14 (OH)6](OH)2, where R is an alkyl group, is sometimes referred to as "MOR" below. A 0.01 M MOR solution was prepared as photoresist composition 1.

[0076] Photoresist composition 2 A ketal compound represented by the following formula was prepared as a sensitizer precursor (PP).

[0077] [ka]

[0078] A liquid photoresist composition 2 was obtained by mixing 33.3 g of photoresist composition 1 with 60 mg of sensitizer precursor (PP).

[0079] (Rating 1) Test 1-1: Photoresist composition 1 (MOR), no UV exposure. Photoresist composition 1 was coated onto a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The entire surface of the resist film was exposed with a KrF excimer laser. After exposure, the resist film was baked by heating at 180°C for 60 seconds. The baked resist film was developed with 2-heptanone. The thickness of the resist film after development was measured using a thickness gauge (Aresis 8350, Toho Technology Co., Ltd.). The same test was performed multiple times while changing the dose of the KrF excimer laser, thereby determining the relationship between the thickness of the resist film after development and the dose of the KrF excimer laser.

[0080] Test 1-2: Photoresist composition 2 (MOR / PP), no UV exposure. Photoresist composition 2 was coated onto a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The entire surface of the resist film was exposed with a KrF excimer laser. After exposure, the resist film was baked by heating at 160°C for 60 seconds. The baked resist film was developed with 2-heptanone. The thickness of the resist film after development was measured using a thickness gauge (Aresis 8350, Toho Technology Co., Ltd.). The same test was performed multiple times while changing the dose of the KrF excimer laser, thereby determining the relationship between the thickness of the resist film after development and the dose of the KrF excimer laser.

[0081] Test 1-3: Photoresist composition 2 (MOR / PP), with UV exposure. Photoresist composition 2 was coated onto a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The entire surface of the resist film was exposed with a KrF excimer laser, followed by exposure with ultraviolet light at wavelengths of 395 nm and 365 nm. After exposure, the resist film was baked by heating at 160°C for 60 seconds. The baked resist film was developed with 2-heptanone. The thickness of the resist film after development was measured using a thickness gauge (Aresis 8350, Toho Technology Co., Ltd.). The same test was performed multiple times while changing the dose of the KrF excimer laser, thereby determining the relationship between the thickness of the resist film after development and the dose of the KrF excimer laser.

[0082] result Figure 9 is a graph showing the relationship between the thickness of the resist film after development and the dose of the KrF excimer laser. In all tests, the resist film became insoluble in the developer (2-heptanone) after exposure to a certain dose of radiation. It was confirmed that by using a photoresist composition containing MOR and a sensitizer precursor (PP), as in Test 1-3, and combining exposure with a KrF excimer laser and subsequent UV exposure, patterning with a lower dose and higher contrast is possible compared to using MOR alone, as in Test 1-1.

[0083] (Rating 2) Test 2-1: Photoresist composition 1 (MOR), no UV exposure. Photoresist composition 1 was coated onto a SOC film formed on a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The resist film was exposed with a KrF excimer laser through a mask having a pattern corresponding to a half-pitch of 150 nm lines / space. The dose of the irradiated KrF excimer laser was 94.3 J / cm². 2 The resist film was then baked at 180°C for 60 seconds after exposure. The baked resist film was developed with 2-heptanone. After development, the line edge roughness (LER) of the formed linear resist pattern was measured by observing it with a scanning electron microscope. The LER was 28.6 nm.

[0084] Test 2-2: Photoresist composition 2 (MOR / PP), no UV exposure. Photoresist composition 2 was coated onto a SOC film formed on a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The resist film was exposed with a KrF excimer laser through a mask having a pattern corresponding to a half-pitch of 150 nm lines / space. The dose of the irradiated KrF excimer laser was 95.6 J / cm². 2The resist film was then baked at 160°C for 60 seconds after exposure. The baked resist film was developed with 2-heptanone. After development, the line edge roughness (LER) of the formed linear resist pattern was measured by observing it with a scanning electron microscope. The LER was 16.3 nm.

[0085] Test 2-3: Photoresist composition 2 (MOR / PP), with UV exposure. Photoresist composition 2 was coated onto a SOC film formed on a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The resist film was exposed with a KrF excimer laser through a mask having a pattern corresponding to a half-pitch of 150 nm lines / space. The mask was immediately removed thereafter, and the entire resist film was exposed to ultraviolet light at wavelengths of 395 nm and 365 nm. The dose from the KrF excimer laser was 87.6 J / cm². 2 The ultraviolet radiation dose is 2.5 J / cm². 2 The resist film was then baked at 160°C for 60 seconds after exposure. The baked resist film was developed with 2-heptanone. After development, the line edge roughness (LER) of the formed linear resist pattern was measured by observing it with a scanning electron microscope. The LER was 16.2 nm.

[0086] Test 2-4: Photoresist composition 2 (MOR / PP), with UV exposure. The dose of the KrF excimer laser was 84.8 J / cm². 2 The ultraviolet radiation dose was changed to 5 J / cm². 2 Aside from the change made, the resist pattern was formed and its LER was measured in the same manner as in Test 2-3. The LER was 16.0 nm.

[0087] result Table 1 shows the evaluation results. As shown in Test 2-2, the LER of the resist pattern was reduced by using a photoresist composition containing MOR and a sensitizer precursor (PP). Furthermore, it was confirmed that the dose of the KrF excimer laser could be further reduced while maintaining the reduced roughness of the resist pattern by adding a step of simultaneous exposure to ultraviolet light, as shown in Tests 2-3 and 2-4. [Table 1]

[0088] (Rating 3) Test 3-1: Photoresist composition 1 (MOR), no UV exposure. Photoresist composition liquid 1 was applied onto a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a resist film with a thickness of 22 nm. The entire surface of the resist film was irradiated with an electron beam in a vacuum with an irradiation current of 100 pA and an acceleration voltage of 150 kV in a line / space pattern with a half-pitch of 12 nm. Subsequently, the resist film was baked by heating at 180°C for 60 seconds. The baked resist film was developed with 2-heptanone. After development, the line width roughness (LWR) and line edge roughness (LER) of the resist pattern were measured by observing the formed linear resist pattern with a scanning electron microscope. The LWR was 1.7 nm and the LER was 2.1 nm.

[0089] Test 3-2: Photoresist composition 2 (MOR / PP), no UV exposure. Photoresist composition 2 was coated onto a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The entire surface of the resist film was irradiated with an electron beam in a vacuum with an irradiation current of 100 pA and an acceleration voltage of 150 kV in a line / space pattern with a half-pitch of 12 nm. Subsequently, the resist film was baked by heating at 160°C for 60 seconds. The baked resist film was developed with 2-heptanone. After development, the line width roughness (LWR) and line edge roughness (LER) of the resist pattern were measured by observing the formed linear resist pattern with a scanning electron microscope. The LWR was 0.99 nm and the LER was 1.8 nm.

[0090] Test 3-3: Photoresist composition 2 (MOR / PP), with UV exposure. Photoresist composition 2 was coated onto a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The entire surface of the resist film was irradiated with an electron beam in a vacuum with an irradiation current of 100 pA and an acceleration voltage of 150 kV in a line / space pattern with a half-pitch of 12 nm. Immediately thereafter, the entire surface of the resist film was exposed to ultraviolet light with a wavelength of 395 nm (exposure dose: 5 J / cm²). 2 The resist film was exposed to light. The exposed resist film was baked by heating at 160°C for 60 seconds. The baked resist film was developed with 2-heptanone. After development, the line width roughness (LWR) and line edge roughness (LER) of the formed linear resist pattern were measured by observing it with a scanning electron microscope. The LWR was 0.92 nm and the LER was 1.6 nm.

[0091] result The evaluation results are shown in Table 2. It was confirmed that even with a combination of electron beam pattern exposure followed by simultaneous UV exposure, a resist pattern with reduced roughness can be formed with a lower radiation dose.

[0092] [Table 2]

[0093] (Rating 4) Test 4-1: Photoresist composition 1 (MOR) Photoresist composition 1 was coated onto a spin-on-glass film formed on a silicon wafer using a spin coater. The solvent was removed by heating the coating at 100°C for 60 seconds to form a 22 nm thick resist film. The entire resist film was irradiated with extreme ultraviolet (EUV) light with a wavelength of 13.5 nm in a vacuum, in a line / space pattern with a half-pitch of 12 nm. Immediately thereafter, the entire resist film was irradiated with ultraviolet light with a wavelength of 365 nm at an exposure dose of 3 J / cm². 2 Low UV dose, or exposure of 5 J / cm² 2 The resist film was exposed to a high UV dose. The resist film was then baked by heating at 160°C for 60 seconds. After baking, the resist film was developed using a developer solution containing propylene glycol monomethyl ether acetate (PGMEA) and acetic acid (AA). After development, the line width (CD) of the formed linear resist pattern was measured by observing it with a length-measuring SEM (CD-SEM). Similar tests were conducted under conditions with different EUV irradiation doses. A similar test was also conducted under conditions without ultraviolet exposure (w / o UV). Figure 10 shows a graph illustrating the relationship between line width (CD) and EUV irradiation dose (relative value) in Test 4-1.

[0094] Test 4-2: Photoresist composition 3 (MOR / PP) Photoresist composition 1 and a sensitizer precursor (PP) were mixed to obtain a liquid photoresist composition 3 containing 5% by mass of PP. The same test as in Test 4-2 was performed, except that photoresist composition 3 was used instead of photoresist composition 1. Figure 11 is a graph showing the relationship between line width (CD) and EUV irradiation dose (relative value) in Test 4-2.

[0095] result Figure 12 is a graph showing the relationship between the CD increase rate (DtS improvement) relative to the CD without UV exposure (without UV exposure) and the amount of UV exposure in Test 4-1 (MOR) or Test 4-2 (MOR / PP). It was confirmed that UV irradiation of a resist film containing non-chemically amplified resist material (MOR) and sensitizer precursor (PP) effectively improved sensitivity.

[0096] (Rating 4) A 22 nm thick resist film was formed by removing the solvent from a photoresist composition 3 containing a non-chemically amplified resist material (MOR) and a sensitizer precursor (PP) by heating at 110°C for 60 seconds. The resist film was irradiated in a vacuum with extreme ultraviolet (EUV) light having a wavelength of 13.5 nm in a pattern including circular areas with a diameter of 24 nm arranged at 48 nm intervals. Subsequently, the resist film was baked by heating at 160°C for 60 seconds. The baked resist film was developed with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH). The resist film in the circular areas irradiated with EUV was selectively removed by development. This test confirmed that the photoresist composition containing a non-chemically amplified resist material (MOR) and a sensitizer precursor (PP) can also function as a positive-type resist material. When a similar test was performed using photoresist composition 1 without the sensitizer precursor (PP), it was confirmed that the resist film was developed as a negative-type resist material. [Explanation of Symbols]

[0097] 1... Semiconductor wafer, 3... Film to be etched, 3A... Patterned film to be etched, 3a, 5a... Trench, 5... Resist film, 5A... Resist pattern, 5E... Part of the resist film irradiated with the first radiation, 7... Mask, R1... First radiation, R2... Second radiation, 11, 12, 13, 14... Processing module, 20... Substrate processing device, 24... Carrier block, 25... Processing block, 26... Interface block, 30... Exposure device, 100... Control device, C... Carrier, W... Workpiece, U1, U2... Processing unit.

Claims

1. Non-chemically amplified resist materials, Sensitizer precursor and Includes, The sensitizer precursor is a compound that, upon irradiation with ionizing radiation or non-ionizing radiation having a wavelength of 300 nm or less, generates a sensitizer that absorbs non-ionizing radiation having a wavelength greater than 300 nm. The non-chemically amplified resist material is a metal oxide photoresist material, and the metal oxide photoresist material comprises an organometallic compound comprising a metal oxide containing metal atoms and an organic ligand bonded to the metal atoms, wherein the organic ligand is detached from the metal atoms by irradiation with non-ionizing radiation having a wavelength greater than 300 nm. Photoresist composition.

2. The photoresist composition according to claim 1, wherein the sensitizer precursor comprises at least one compound selected from the group consisting of acetal compounds, ketal compounds, thioacetal compounds, alcohol compounds, thiol compounds, and orthoester compounds, which generates the sensitizer having a carbonyl group.

3. A photoresist composition according to claim 1 or 2, further comprising a solvent.

4. Irradiating a portion of a resist film containing a non-chemically amplified resist material and a sensitizer precursor with a first radiation, The second radiation is irradiated collectively to the entire region of the resist film, including the portion irradiated with the first radiation and the remaining portion. A portion of the resist film is removed by development, thereby forming a resist pattern. This includes them in this order, When the first radiation is ionizing radiation or non-ionizing radiation, and the second radiation is non-ionizing radiation, and the first radiation is non-ionizing radiation, the second radiation is non-ionizing radiation having a wavelength longer than the wavelength of the first radiation. The sensitizer precursor is a compound that generates a sensitizer that absorbs the second radiation upon irradiation with the first radiation. The non-chemically amplified resist material is a metal oxide photoresist material, and the metal oxide photoresist material comprises an organometallic compound comprising a metal oxide containing metal atoms and an organic ligand bonded to the metal atoms, wherein the organic ligand is detached from the metal atoms upon irradiation with the second radiation. A method for forming a resist pattern.

5. The method according to claim 4, wherein the sensitizer precursor comprises at least one compound selected from the group consisting of acetal compounds, ketal compounds, thioacetal compounds, alcohol compounds, thiol compounds, and orthoester compounds, which causes the sensitizer having a carbonyl group to produce the sensitizer.

6. The first radiation is ionizing radiation or non-ionizing radiation having a wavelength of 300 nm or less. The second radiation is non-ionizing radiation having a wavelength greater than 300 nm. The method according to claim 4 or 5.

7. The method according to claim 4 or 5, further comprising baking the resist film between the irradiation of the first radiation and the irradiation of the second radiation, after the irradiation of the second radiation, or both thereof.

8. A method for manufacturing a semiconductor device having a patterned film, wherein the method is A resist pattern having trenches in which the etched film is exposed is formed on the etched film by the method of claim 4 or 5, Etching the film to be etched exposed in the trench, thereby patterning the film to be etched, Methods that include...

9. A film forming unit that forms a resist film containing a non-chemically amplified resist material and a sensitizer precursor on a workpiece having a film to be etched, An exposure unit that irradiates the resist film having a portion irradiated with a first radiation with a second radiation, A developing unit that removes a portion of the resist film by developing, thereby forming a resist pattern, A control unit controls the exposure unit such that the second radiation is irradiated simultaneously over the entire region of the resist film, including the portion irradiated by the first radiation and the remaining portion. Equipped with, When the first radiation is ionizing radiation or non-ionizing radiation, and the second radiation is non-ionizing radiation, and the first radiation is non-ionizing radiation, the second radiation is non-ionizing radiation having a wavelength longer than the wavelength of the first radiation. The non-chemically amplified resist material is a metal oxide photoresist material, and the metal oxide photoresist material comprises an organometallic compound comprising a metal oxide containing metal atoms and an organic ligand bonded to the metal atoms, wherein the organic ligand is detached from the metal atoms upon irradiation with the second radiation. Circuit board processing equipment.

10. The substrate processing apparatus, A processing block including the film forming unit, the exposure unit, and the developing unit, An interface block including a transfer unit for transferring a workpiece having the resist film between the processing block and the exposure apparatus that irradiates a portion of the resist film with the first radiation, Equipped with, The substrate processing apparatus according to claim 9, wherein the control unit controls the transport unit so that the workpiece having the resist film irradiated with the first radiation is transported to the exposure unit in the exposure apparatus.

11. The substrate processing apparatus according to claim 9 or 10, wherein the film forming unit includes a coating unit for coating a photoresist composition comprising the non-chemically amplified resist material and the sensitizer precursor onto the workpiece.

12. The substrate processing apparatus according to claim 11, wherein the film forming unit further includes a heat treatment unit that bakes the film of the applied photoresist composition to form a resist film containing the non-chemically amplified resist material and the sensitizer precursor on the film to be etched.

Images