Reactive materials, and method of manufacturing thin film

Abstract

The present invention provides a reactive material containing a compound represented by the following general formula (1) or (2); (In equation (1), R) 1. R 2. R 3 and R 4. Each can independently represent a hydrocarbon group or an electron-withdrawing group with 1 to 4 carbon atoms; however, R 1. R 2. R 3 and R (at least one of the four groups represents an electron-withdrawing group); (In equation (2), R) 5 and R 6. Each can independently represent a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms, or an electron-withdrawing group; however, R 5 and R At least one of the 6 represents an electron-withdrawing group.

Description

[Technical Field]

[0001] This invention relates to a reactive material for reducing organometallic compounds to metals and a method for manufacturing a thin film using the same. [Previous Technology]

[0002] Ruthenium thin films exhibit unique electrical properties and are used in a variety of applications. For example, they are known to be used as electrode materials for memory devices, such as DRAM devices, resistive films, antimagnetic films used in the recording layers of hard disks, catalyst materials for solid polymer fuel cells, wiring materials for semiconductor devices, and metal gate materials for MOS-FETs, etc.

[0003] Examples of methods for manufacturing thin films include sputtering, ion plating, coating thermal decomposition, sol-gel methods, and chemical vapor deposition (CVD). Among these, chemical vapor deposition, which includes CVD and atomic layer deposition (ALD), is mainly used due to its advantages such as excellent composition control and step coverage, suitability for mass production, and ability to be integrated.

[0004] Various organorruthenium compounds are known as organic ruthenium compounds used in chemical vapor deposition methods such as CVD and ALD. For example, Patent Document 1 discloses a method for manufacturing a ruthenium-containing thin film using a mixture of ruthenium complexes containing two or more ruthenium complexes and a reducing gas. Patent Document 2 discloses a method for manufacturing a ruthenium-containing thin film using a ruthenium compound as a raw material for thin film formation, wherein the ruthenium compound is composed of two six-membered rings containing two carbonyl groups, ruthenium atoms, and ketimine groups in its ring structure. Patent Document 3 discloses a method for manufacturing a metallic ruthenium thin film, comprising: a step of depositing a ruthenium compound having a cyclohexanediene and a benzene ring in its structure onto a substrate, and a step of reacting the ruthenium compound deposited on the substrate with a reactive gas containing a specific compound. [Prior Art Documents] [Patent Documents]

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-118605; Patent Document 2: Japanese Invention Patent No. 6509128; Patent Document 3: International Publication No. 2020 / 095744 [Summary of the Invention]

[0006] [The problem that the invention aims to solve]

[0007] However, in conventional methods for manufacturing ruthenium thin films using the ALD method, there is a problem of forming composite films containing ruthenium and ruthenium oxide, resulting in ruthenium films with a high residual carbon content. Composite films containing ruthenium oxide need to be treated at high temperatures to reduce them back to ruthenium, which can damage the substrate and surrounding components.

[0008] Therefore, the object of the present invention is to provide a method for manufacturing high-quality ruthenium thin films with low ruthenium oxide content and low residual carbon content, and a reactive material using the same. [Means for Solving the Problem]

[0009] As a result of repeated and dedicated review, the inventors discovered that the above-mentioned problems could be solved by using reactive materials containing specific compounds, and finally completed the present invention.

[0010] That is, the present invention is represented by the following [1] to [8].

[0011] [1] A reactive material containing a compound represented by the following general formula (1) or (2);

[0012]

[0013] (In formula (1), R1, R2, R3 and R4 each independently represent a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms or an electron-withdrawing group; the electron-withdrawing group is selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl and sulfomethyl; however, at least one of R1, R2, R3 and R4 represents an electron-withdrawing group).

[0014]

[0015] (In formula (2), R5 and R6 each independently represent a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms, or an electron-withdrawing group; the electron-withdrawing group is selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl, and sulfomethyl; however, at least one of R5 and R6 represents an electron-withdrawing group).

[0016] [2] The reactive material described in [1] is used to reduce organometallic compounds to metals.

[0017] [3] A method for manufacturing a thin film, comprising an atomic layer deposition process, using a reactive material as described in [1] or [2] to form a ruthenium thin film.

[0018] [4] The method for manufacturing a thin film as described in [3] includes the steps of forming a precursor film using a raw material for forming a thin film containing an organorruthenium compound; and reacting the aforementioned precursor film with the aforementioned reactive material to form a metallic ruthenium film.

[0019] [5] The method for manufacturing a thin film as described in [4], wherein the aforementioned organorruthenium compound is selected from the group consisting of organorruthenium compounds represented by the following general formula (3), organorruthenium compounds represented by the following general formula (4) and organorruthenium compounds represented by the following general formula (5);

[0020]

[0021] (In formulas (3), (4) and (5), L1 represents a covalent ligand selected from the group consisting of aminoalkoxy, amidinate group, β-diketonate group, β-ketoiminate group, β-diketoniminate group, groups with a 2,4-pentadienyl structure and groups with a cyclopentadienyl structure, X represents a halogen atom, n represents an integer from 0 to 2, L2 represents an electron-donating ligand selected from the group consisting of carbonyl, cyano, trialkylphosphine compounds and isocyanide compounds, m represents an integer from 0 to 3, L3 represents an electron-donating ligand selected from the group consisting of chain diene compounds, cyclic diene compounds, chain polyene compounds and cyclic polyene compounds, y represents 1 or 2, L4 represents an electron-donating ligand containing aromatic compounds, z represents 0 or 1).

[0022] [6] The method for manufacturing a thin film as described in [4] or [5] involves depositing the vaporized raw material for forming the aforementioned thin film onto the surface of a substrate heated to 100°C to 450°C to form the aforementioned precursor thin film.

[0023] [7] The method for manufacturing a thin film as described in [6] further includes, after forming the aforementioned precursor thin film, a step of venting the undeposited raw material for forming the aforementioned thin film from the reaction system.

[0024] [8] The method for manufacturing a thin film as described in [7] further includes, after forming the aforementioned ruthenium thin film, a step of venting unreacted reactive material from the reaction system; and repeating the following steps: the step of forming a precursor thin film, the step of venting undeposited raw material for forming the thin film from the reaction system, the step of forming the ruthenium thin film, and the step of venting unreacted reactive material from the reaction system. [Effects of the Invention]

[0025] According to the present invention, a method for producing high-quality ruthenium thin films with low ruthenium oxide content and low residual carbon content, and reactive materials using the same are provided.

Implementation Method

[0027] [Form of the invention]

[0028] The present invention relates to a reactive material containing a compound represented by the above general formula (1) or (2). Here, a reactive material is a material that can reduce an organometallic compound to a metal, and more specifically, a material that can react with a precursor film formed from a precursor containing an organometallic compound to form a metal film. The metal in the metal film is a metal derived from the metal of the precursor. The reactive material of the present invention is not limited by the metal of the precursor, but from the viewpoint of good reactivity, it is preferable to react with a precursor film formed from a precursor containing an organorurus compound.

[0029] In the above general formula (1), the hydrocarbon groups with 1 to 4 carbon atoms represented by R1, R2, R3 and R4 can be saturated hydrocarbon groups and unsaturated hydrocarbon groups. Examples of saturated hydrocarbon groups include alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, dibutyl, and tributyl. Examples of unsaturated hydrocarbon groups include alkenyl alkyl groups such as allylmethyl and propenylmethyl, and alkynyl alkyl groups such as ethynylmethyl.

[0030] From the viewpoint that metal ruthenium thin films with few ruthenium oxides can be easily formed by reacting with organor ruthenium compounds at low temperatures, it is preferable that two or more of R1, R2, R3 and R4 in the above general formula (1) are electron-withdrawing groups, and it is even more preferable that three or more are electron-withdrawing groups.

[0031] The electron-withdrawing groups represented by R1, R2, R3 and R4 in the above general formula (1) are selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl and sulfomethyl.

[0032] When two or more of R1, R2, R3, and R4 are electron-withdrawing groups, the types of electron-withdrawing groups in a molecule may be different, but are preferably the same. When three of R1, R2, R3, and R4 are electron-withdrawing groups, the electron-withdrawing groups are preferably halogen atoms such as fluorine, chlorine, bromine, and iodine. When all of R1, R2, R3, and R4 are electron-withdrawing groups, from the viewpoint of easily forming ruthenium thin films with few ruthenium oxides, the electron-withdrawing groups are preferably cyano groups.

[0033] When at least one of R1, R2, R3 and R4 is not an electron-withdrawing group, from the viewpoint of easily forming a ruthenium thin film with few ruthenium oxides, at least one of R1, R2, R3 and R4 is preferably a hydrogen atom or a methyl group.

[0034] From the viewpoint that the reactive material of the present invention can easily form a thin film of metal with few ruthenium oxides, it is preferably a compound containing at least one of R1, R2, R3 and R4 in the above general formula (1) that is a fluorine atom, chlorine atom, bromine atom, iodine atom, cyano or trifluoromethyl, and more preferably a compound containing a fluorine atom, chlorine atom, bromine atom, iodine atom or cyano.

[0035] As preferred examples of compounds represented by the above general formula (1), compounds No. 1 to No. 225 below can be cited as examples. However, the present invention is not limited to these compounds. Furthermore, in the following, "Me" represents methyl, "CF3" represents trifluoromethyl, "CCl3" represents trichloromethyl, "CBr3" represents tribromomethyl, "CI3" represents triiodomethyl, "CN" represents cyano, "CHO" represents aldehyde, "COCH3" represents acetyl, "COOH" represents carboxyl, "COOCH3" represents carboxymethyl, "SO3H" represents sulfonyl, and "SO2CH3" represents sulfomethyl.

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051] The compounds represented by the above general formula (1) are not particularly limited by their manufacturing method and can be manufactured by well-known synthetic methods. For example, the compound of No. 135 can be obtained by dibrominating malononitrile with bromine and then dimerizing it by reduction with copper powder.

[0052] Examples of compounds having two electron withdrawing groups include No. 7 to No. 12, No. 22 to No. 27, No. 37 to No. 42, No. 52 to No. 57, No. 67 to No. 72, No. 82 to No. 87, No. 97 to No. 102, and No. 1 12~No.117, No.127~No.132, No.142~No.147, No.157~No.162, No.172~No.177, No.187~No.192, No.202~No.207 and No.217~No.222 compounds.

[0053] Examples of compounds having three or more electron-withdrawing groups include compounds No. 13-15, No. 28-30, No. 43-45, No. 58-60, No. 73-75, No. 88-90, No. 103-105, No. 118-120, No. 133-135, No. 148-150, No. 163-165, No. 178-180, No. 193-195, No. 208-210, and No. 223-225. Among these, compounds No. 43 and No. 135 are preferred from the viewpoint that the effects of the present invention become more significant.

[0054] Next, the compound represented by general formula (2) will be described. In the above general formula (2), the hydrocarbon groups with 1 to 4 carbon atoms represented by R5 and R6 can be the same as those described by R1, R2, R3 and R4 in the above general formula (1). In the above general formula (2), the electron-withdrawing groups represented by R5 and R6 can be the same as those described by R1, R2, R3 and R4 in the above general formula (1).

[0055] As a preferred example of the compound represented by the above general formula (2), compounds No. 226 to No. 270 can be cited for example. However, the present invention is not limited to such compounds.

[0056]

[0057]

[0058] The compounds represented by the above general formula (2) are not particularly limited by their manufacturing method and can be manufactured by well-known synthetic methods. For example, the compound No. 232 can be obtained by heating and stirring 1,2-dibromoethane in a mixed solvent of ethanol and water in the presence of sodium hydroxide.

[0059] In the above general formula (2), at least one of R5 and R6 may be an electron-withdrawing group, or both of R5 and R6 may be electron-withdrawing groups. When both R5 and R6 are electron-withdrawing groups, they may be the same electron-withdrawing group or they may be different electron-withdrawing groups. Examples of compounds in which both R5 and R6 are electron-withdrawing groups include compounds No. 228, No. 231, No. 234, No. 237, No. 240, No. 243, No. 246, No. 249, No. 252, No. 255, No. 258, No. 261, No. 264, No. 267 and No. 270.

[0060] The reactive material of the present invention contains a compound represented by the above general formula (1) or the above general formula (2). It may be a reactive material composed solely of the compound represented by the above general formula (1), or a reactive material composed solely of the compound represented by the above general formula (2), or a mixture of the compound represented by the above general formula (1) and the compound represented by the above general formula (2). Furthermore, the reactive material of the present invention may further contain reactants such as water vapor, nitrogen, oxygen, ozone, and hydrogen used for the formation of thin films.

[0061] When the reactive material of the present invention is a mixture of the compound shown in general formula (1) and the compound shown in general formula (2), from the viewpoint of easily forming a ruthenium thin film with low ruthenium oxide content, the compound shown in general formula (1) is preferably 60 parts by mass or more, more preferably 80 parts by mass or more, particularly preferably 90 parts by mass or more, and most preferably 98 parts by mass or more, relative to a total of 100 parts by mass of the compound shown in general formula (1) and the compound shown in general formula (2). From the viewpoint of easily forming a ruthenium thin film with low ruthenium oxide content, the reactive material of the present invention preferably contains only the compound shown in general formula (1).

[0062] From the viewpoint that it is easy to form a thin film of metal with few ruthenium oxides, the total amount of the compound shown in the above general formula (1) and the compound shown in the above general formula (2) is preferably 60% by volume or more, more preferably 70% by volume or more, even more preferably 90% by volume or more, even more preferably 98% by volume or more, and most preferably 99% by volume or more, relative to the total reactive material.

[0063] Next, a method for manufacturing the thin film of the present invention will be described. The method for manufacturing the thin film of the present invention includes an atomic layer deposition process, in which the above-mentioned reactive material is used to form a ruthenium thin film.

[0064] The preferred method for manufacturing the thin film of the present invention comprises: a step of forming a precursor thin film using a raw material containing an organorruthenium compound (precursor thin film forming step), and a step of reacting the precursor thin film with the aforementioned reactive material to form a metallic ruthenium thin film (thin film forming step). Because these steps are included, it is preferable to easily form a high-quality metallic ruthenium thin film with low ruthenium oxide content and low residual carbon content.

[0065] Hereinafter, the raw materials for thin film formation used in the thin film manufacturing method of the present invention will be described.

[0066] <Film Forming Raw Materials> The film forming raw materials used in the precursor film forming step contain organorruthenium compounds.

[0067] As for the organorruthenium compound contained in the above-mentioned raw material for thin film formation, it can be used without particular restriction as long as the raw material for thin film formation is a well-known organorruthenium compound. However, from the viewpoint that the effect of the present invention becomes more significant, it is preferable to select the group consisting of the organorruthenium compound shown in the following general formula (3), the organorruthenium compound shown in the following general formula (4) and the organorruthenium compound shown in the following general formula (5).

[0068]

[0069] In the above general formulas (3), (4) and (5), L1 represents a covalent ligand selected from the group consisting of aminoalkoxy, amidine, β-diketo, β-ketoimine, β-diketoimine, groups having a 2,4-pentadienyl structure and groups having a cyclopentadienyl structure, X represents a halogen atom, n represents an integer from 0 to 2, L2 represents an electron-donating ligand selected from the group consisting of carbonyl, cyano, trialkylphosphine compounds and isocyanide compounds, m represents an integer from 0 to 3, L3 represents an electron-donating ligand selected from the group consisting of chain diene compounds, cyclic diene compounds, chain polyene compounds and cyclic polyene compounds, y represents 1 or 2, L4 represents an electron-donating ligand containing aromatic compounds, and z represents 0 or 1.

[0070] Aminoalkoxy groups, such as aminomethoxy, methylaminomethoxy, dimethylaminomethoxy, ethylmethylaminomethoxy, diethylaminomethoxy, 2-aminoethoxy, 2-(methylamino)ethoxy, 2-(dimethylamino)ethoxy, 2-(ethylmethyl)aminoethoxy, 2-(diethylamino)ethoxy, (1-(dimethylamino)propane-2-yl)oxy, (1-(ethylmethylamino)propane-2-yl)oxy, (1-(dimethylamino)propane-2-yl)oxy, (1-(dimethylamino)propane-2-yl)oxy, (1-(dimethylamino)propane-2-yl)oxy, (1-(dimethylamino)propane-2-yl)oxy, (1-(dimethylamino)2-methylpropane-2-yl)oxy, ( 1-(diethylamino)propane-2-yl)oxy, (1-(dimethylamino)propane-2-yl)oxy, (1-(ethylmethylamino)propane-2-yl)oxy, (1-(diethylamino)propane-2-yl)oxy, 3-(dimethylamino)propoxy, (ethylmethylamino)propoxy, (diethylamino)propoxy, (4-(dimethylamino)butane-2-yl)oxy, (4-(ethylmethylamino)butane-2-yl)oxy, (4-(diethylamino)butane-2-yl)oxy, 4-(dimethylamino)-2-methylbutane-2-yl)oxy, 4-(diethylamino)-2-methylbutane-2-yl)oxy, 4-(diethylamino)-2-methylbutane-2-yl)oxy, 4-(diethylamino)-2-methylbutane-2-yl)oxy, etc.

[0071] Amino groups that are covalent ligands represented by L1 in the above general formulas (3) and (4) can be, for example, N,N'-dimethylacetamino, N,N'-diethylacetamino, N,N'-diisopropylacetamino, N,N'-n-propylacetamino, N,N'-ditert-butylethylpropionimino, N,N'-trifluoromethylbenzo[a]amino, N,N'-diphenylbenzo[a]amino, N,N'-bistrimethylsilylbenzo[a]amino, etc.

[0072] The β-diketone group, which is the covalently bonded ligand represented by L1 in the above general formulas (3) and (4), can be exemplified by acetoacetone, trifluoroacetoacetone, hexafluoroacetoacetone, dimethylheptanedione, tetramethylheptanedione, heptafluorodimethyloctanedione, tetradecanofluorononanedione, trifluorodimethylhexanedione, octafluorohexanedione, pentafluorodimethylheptanedione, decafluoroheptanedione, dimethylmethoxyoctanedione, trichloropentanedione, diphenylpropanedione, etc.

[0073] The β-keto imine group, which is the covalently bonded ligand represented by L1 in the above general formulas (3) and (4), can be exemplified by the β-keto imine group described in Japanese Patent Application Publication No. 2002-533910, Japanese Patent Application Publication No. 2002-302473, and Japanese Patent Application Publication No. 2011-061208.

[0074] The β-diketone imine group, which is the covalently bonded ligand represented by L1 in the above general formulas (3) and (4), can be exemplified by the β-diketone imine group described in Japanese Patent Application Publication No. 8-36420, etc.

[0075] The covalently bonded ligands represented by L1 in the above general formulas (3) and (4) that have a 2,4-pentadienyl structure can be exemplified by, for example, hex-2,4-dienyl, 4-methylhex-2,4-dienyl, 2,4-dimethylpent-2,4-dienyl, 2,4-diethylpent-2,4-dienyl, 2,4-diisopropylpent-2,4-dienyl, etc.

[0076] The covalently bonded ligands represented by L1 in the above general formulas (3) and (4) are cyclopentadienyl groups, for example, cyclopentadienyl, methylpentadienyl, ethylcyclopentadienyl, pentamethylcyclopentadienyl, etc.

[0077] As for the halogen atom represented by X in the above general formula (4), examples include fluorine atom, chlorine atom, bromine atom, iodine atom, etc.

[0078] For example, trialkylphosphine compounds that are electron-donating ligands represented by L2 in the above general formulas (4) and (5) include trimethylphosphine, triethylphosphine, tritertylphosphine, tricyclohexylphosphine, etc.

[0079] The isonitrile compound that is an electron-donating ligand represented by L2 in the above general formulas (4) and (5) represents a group containing the structure of R7-N≡C, where R7 represents a straight-chain or branched alkyl group with 1 to 6 carbon atoms or a cycloalkyl group with 3 to 6 carbon atoms.

[0080] As shown in R7, the linear or branched alkyl group having 1 to 6 carbon atoms can be exemplified by methyl, ethyl, propyl, isopropyl, butyl, isobutyl, dibutyl, terbutyl, pentyl, hexyl, etc.

[0081] Examples of cycloalkyl groups having 3 to 6 carbon atoms as shown in R7 include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl.

[0082] Examples of chain diene compounds that are electron-donating ligands as L3 in the above general formula (5) include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 2,3-dimethyl-1,3-pentadiene, 2,4-dimethyl-1,3-pentadiene, 2,4-hexadiene, 3-methyl-1,3-pentadiene, 2-ethyl-1,3-butadiene, 1,3-hexadiene, 1,3-heptadiene, 1,3-octadiene, 1,3-nonadiene, 1,3-decadiene, 2-isopropyl-2,3-butadiene, and 2-cyclohexyl-1,3-butadiene.

[0083] Examples of cyclic diene compounds that are electron-donating ligands as L3 in the above general formula (5) include 1,3-cyclohexadiene, 1,4-cyclohexadiene, 1-methyl-1,3-cyclohexadiene, 2-methyl-1,3-cyclohexadiene, 1-ethyl-1,3-cyclohexadiene, 2-ethyl-1,3-cyclohexadiene, 1-propyl-1,3-cyclohexadiene, 2-propyl-1,3-cyclohexadiene, 1-isopropyl-1,3-cyclohexadiene, 2-isopropyl-1,3-cyclohexadiene, 1-butyl-1,3-cyclohexadiene, 2-butyl-1,3-cyclohexadiene, and 1-isobutyl-1,3-cyclohexadiene. Alkenes, 2-isobutyl-1,3-cyclohexadiene, 1-dibutyl-1,3-cyclohexadiene, 2-dibutyl-1,3-cyclohexadiene, 1-tert-butyl-1,3-cyclohexadiene, 2-tert-butyl-1,3-cyclohexadiene, 1-pentyl-1,3-cyclohexadiene, 2-pentyl-1,3-cyclohexadiene, 1-hexyl-1,3-cyclohexadiene, 2-hexyl-1,3-cyclohexadiene, 1-cyclohexyl-1,3-cyclohexadiene, 2-cyclohexyl-1,3-cyclohexadiene, α-phellandrene, α-terpinene, γ-terpinene, norcamphede, 1,5-cyclooctadiene, 1,5-dimethyl-1,5-cyclooctadiene, etc.

[0084] In this invention, a polyene compound refers to a carbon compound having three or more carbon-carbon double bonds in one molecule. Examples of chain polyene compounds with electron-donating ligands as L3 in general formula (5) include 1,3,5-hextriene and 1,3,5-hepttriene. Examples of cyclic polyene compounds with electron-donating ligands as L3 in the above general formula (5) include cyclohepttriene, cycloocttriene, and cyclooctatetraene.

[0085] Examples of aromatic compounds that are electron-donating ligands as L4 in the above general formula (5) include toluene, benzene, o-xylene, m-xylene, p-xylene, mesitylene, fluorobenzene, o-difluorobenzene, p-difluorobenzene, chlorobenzene, pentafluorobenzene, o-dichlorobenzene, hexafluorobenzene, etc.

[0086] From the viewpoint that the effects of the present invention are significant, it is preferable that L1 in the above general formula (3) is an organorruthenium compound of amidoyl, β-diketoyl, β-ketoimino, β-diketoimino, 2,4-pentadienyl or cyclopentadienyl, and more preferably an organorruthenium compound of β-diketoyl, β-ketoimino or β-diketoimino.

[0087] As preferred examples of the organorruthenium compounds represented by the above general formula (3), compounds No. 271 to No. 275 can be cited below. However, the present invention is not limited to these organorruthenium compounds.

[0088]

[0089] From the viewpoint that the effects of the present invention are significant, it is preferable that L1 in the above general formula (4) is an organorruthenium compound of amidoyl, β-diketoyl, β-ketoimino, β-diketoimino, 2,4-pentadienyl or cyclopentadienyl, more preferably an organorruthenium compound of amidoyl, β-diketoyl, β-diketoimino, 2,4-pentadienyl or cyclopentadienyl, and even more preferably an organorruthenium compound of 2,4-pentadienyl or cyclopentadienyl.

[0090] From the viewpoint that the effects of the present invention are significant, it is preferable that X in the above general formula (4) is an organorruthenium compound containing chlorine atoms.

[0091] From the viewpoint that the effects of the present invention are significant, it is preferable that L2 in the above general formula (4) is an organorruthenium compound of carbonyl, cyano or trialkylphosphine, and more preferably an organorruthenium compound of carbonyl or cyano.

[0092] From the viewpoint that the effects of the present invention are significant, it is preferable that the organorruthenium compound in the above general formula (4) has n of 0 or 2, and more preferably an organorruthenium compound with n of 2.

[0093] From the viewpoint that the effects of the present invention are significant, it is preferable that m in the above general formula (4) is an organorruthenium compound of 0 or 2, and more preferably an organorruthenium compound of 2.

[0094] As preferred examples of the organorruthenium compounds represented by the above general formula (4), compounds No. 276 to No. 305 can be cited below. However, the present invention is not limited to these organorruthenium compounds.

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101] From the viewpoint that the effects of the present invention are significant, it is preferable that L2 in the above general formula (5) is an organorruthenium compound of carbonyl, cyano or trialkylphosphine, and more preferably an organorruthenium compound of carbonyl or cyano.

[0102] From the viewpoint that the effects of the present invention are significant, it is preferable that L3 in the above general formula (5) is an organorruthenium compound of a chain diene compound, a cyclic diene compound or a cyclic polyene compound, and more preferably an organorruthenium compound of a chain diene compound or a cyclic diene compound.

[0103] From the viewpoint that the effects of the present invention are significant, it is preferable that L4 in the above general formula (5) is an organorruthenium compound of toluene, benzene, o-xylene, m-xylene or p-xylene, and more preferably an organorruthenium compound of toluene or benzene.

[0104] From the viewpoint that the effects of the present invention are significant, it is preferable that the m in the above general formula (5) is an organorruthenium compound of 0 or 2, and more preferably an organorruthenium compound of 0.

[0105] From the viewpoint that the effects of the present invention are significant, it is preferable that the organorruthenium compound in the above general formula (5) is 1 or 2, and more preferably an organorruthenium compound is 1.

[0106] From the viewpoint that the effects of the present invention are significant, it is preferable that the organorruthenium compound in the above general formula (5) has z as 0 or 1, and more preferably an organorruthenium compound with z as 0.

[0107] As preferred examples of the organorruthenium compounds represented by the above general formula (5), compounds No. 306 to No. 318 can be cited below. However, the present invention is not limited to these organorruthenium compounds.

[0108]

[0109]

[0110]

[0111] In the method for manufacturing the thin film of the present invention, the structure of the organorruthenium compound is not limited and a mixture of organorruthenium compounds may be used. However, from the viewpoint that the effect of the present invention is more significant, it is preferable to use the organorruthenium compound shown in general formula (4) or the organorruthenium compound shown in general formula (5) as the raw material for thin film formation. More preferably, it is preferable to use the raw material for thin film formation containing the organorruthenium compounds selected from No. 281 to No. 318. Most preferably, it is preferable to use the raw material for thin film formation containing the organorruthenium compounds selected from No. 303 to No. 309 or No. 316 to No. 318.

[0112] The raw material for forming a thin film containing an organorruthenium compound may be any material containing an organorruthenium compound as a precursor of the thin film, and its composition may vary depending on the type of thin film intended. For example, when manufacturing a thin film containing only ruthenium atoms as a metal, the raw material for forming the thin film does not contain metal compounds other than ruthenium or half-metal compounds. On the other hand, when manufacturing a thin film containing ruthenium atoms and metals and / or half-metals other than ruthenium atoms, the raw material for forming the thin film may contain, in addition to the organorruthenium compound, a compound containing the desired metal and / or a compound containing half-metals (hereinafter also referred to as "other precursors").

[0113] In the case of ALD process using a multi-component system with multiple precursors, other precursors that can be used with organorruthenium compounds are not particularly restricted, and commonly known precursors used for film forming in ALD process can be used.

[0114] Other precursors mentioned above may include, for example, compounds of one or more types selected from the group consisting of compounds that use alcohols, diols, β-diketones, cyclopentadienes, and organic amines as organic ligands, and compounds with silicon or metals. Furthermore, metals that may be used as precursors may include lithium, sodium, potassium, magnesium, calcium, strontium, barium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, iron, osmium, ruthenium, cobalt, rhodium, iridium, nickel, palladium, platinum, copper, silver, gold, zinc, aluminum, gallium, indium, germanium, lead, gallium, indium, radium, scandium, ruthenium, yttrium, lanthanum, cerium, tungsten, neodymium, cerium, samarium, europium, thorium, tungsten, dysprosium, holmium, erbium, thorium, ytterbium, or ferruginium.

[0115] Examples of alcohol compounds used as organic ligands for the aforementioned other precursors include alkyl alcohols such as methanol, ethanol, propanol, isopropanol, butanol, dibutanol, isobutanol, terbutanol, pentanol, isopentanol, and terpentanol; 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-(2-methoxyethoxy)ethanol, 2-methoxy-1-methylethanol, 2-methoxy-1,1-dimethylethanol, 2-ethoxy-1,1-dimethylethanol, 2-isopropoxy-1,1-dimethylethanol, and 2-butoxy-1,1-dimethylethanol. - Ether alcohols such as dimethylethanol, 2-(2-methoxyethoxy)-1,1-dimethylethanol, 2-propoxy-1,1-diethylethanol, 2-dibutoxy-1,1-diethylethanol, and 3-methoxy-1,1-dimethylpropanol; dialkylamino alcohols such as dimethylaminoethanol, ethylmethylaminoethanol, diethylaminoethanol, dimethylamino-2-pentanol, ethylmethylamino-2-pentanol, dimethylamino-2-methyl-2-pentanol, ethylmethylamino-2-methyl-2-pentanol, and diethylamino-2-methyl-2-pentanol.

[0116] Examples of diol compounds used as organic ligands for the other precursors mentioned above include 1,2-ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2,4-hexanediol, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 1,3-butanediol, 2,4-butanediol, 2,2-diethyl-1,3-butanediol, 2-ethyl-2-butyl-1,3-propanediol, 2,4-pentanediol, 2-methyl-1,3-propanediol, 2-methyl-2,4-pentanediol, 2,4-hexanediol, and 2,4-dimethyl-2,4-pentanediol.

[0117] Examples of β-diketone compounds used as organic ligands for the other precursors mentioned above include acetoacetone, hexane-2,4-dione, 5-methylhexane-2,4-dione, heptane-2,4-dione, 2-methylheptane-3,5-dione, 5-methylheptane-2,4-dione, 6-methylheptane-2,4-dione, 2,2-dimethylheptane-3,5-dione, 2,6-dimethylheptane-3,5-dione, 2,2,6-trimethylheptane-3,5-dione, 2,2,6,6-tetramethylheptane-3,5-dione, octane-2,4-dione, 2,2,6-trimethyloctane-3,5-dione, 2,6-dimethyloctane-3,5-dione, and 2,9-dimethylnonane-4,6-dione. Alkyl-substituted β-diketones such as diketones, 2-methyl-6-ethyldecane-3,5-diketones, and 2,2-dimethyl-6-ethyldecane-3,5-diketones; fluorinated alkyl-substituted β-diketones such as 1,1,1-trifluoropentane-2,4-diketones, 1,1,1-trifluoro-5,5-dimethylhexane-2,4-diketones, 1,1,1,5,5,5-hexafluoropentane-2,4-diketones, and 1,3-diperfluorohexylpropane-1,3-diketones; and ether-substituted β-diketones such as 1,1,5,5-tetramethyl-1-methoxyhexane-2,4-diketones, 2,2,6,6-tetramethyl-1-methoxyheptane-3,5-diketones, and 2,2,6,6-tetramethyl-1-(2-methoxyethoxy)heptane-3,5-diketones.

[0118] Examples of cyclopentadiene compounds used as organic ligands for the other precursors mentioned above include cyclopentadiene, methylcyclopentadiene, ethylcyclopentadiene, propylcyclopentadiene, isopropylcyclopentadiene, butylcyclopentadiene, dibutylcyclopentadiene, isobutylcyclopentadiene, terbutylcyclopentadiene, dimethylcyclopentadiene, tetramethylcyclopentadiene, and pentamethylcyclopentadiene.

[0119] Examples of organic amine compounds used as the above-mentioned organic ligands include methylamine, ethylamine, propylamine, isopropylamine, butylamine, dibutylamine, terbutylamine, isobutylamine, dimethylamine, diethylamine, dipropylamine, diisopropylamine, ethylmethylamine, propylmethylamine, isopropylmethylamine, etc.

[0120] The aforementioned other precursors are well known in this technical field, and their manufacturing methods are also well known. For example, using an alcohol compound as an organic ligand precursor can be achieved by reacting an inorganic salt of the aforementioned metal or its hydrate with an alkali metal alkoxide of the alcohol compound. Here, examples of inorganic salts of metals or their hydrates include metal halides and nitrates, and examples of alkali metal alkoxides include sodium alkoxides, lithium alkoxides, and potassium alkoxides.

[0121] In the multi-component ALD method described above, there are methods for independently vaporizing and supplying the thin film forming raw materials as individual components (hereinafter also referred to as the "single-source method"), and methods for vaporizing and supplying a mixture of multi-component raw materials pre-mixed with a desired composition (hereinafter also referred to as the "mixed-source method"). In the case of the single-source method, as the aforementioned other precursor, it is preferable to be a compound whose thermal and / or oxidative decomposition behavior is similar to that of the organorruthenium compounds contained in the thin film forming raw materials. In the case of the mixed-source method, as the aforementioned other precursor, it is preferable to be a compound that, in addition to having a thermal and / or oxidative decomposition behavior similar to that of the organorruthenium compounds contained in the thin film forming raw materials, also deteriorates due to not undergoing chemical reactions during mixing.

[0122] In the case of the mixed source method in the multi-component ALD method, the mixture of the organorruthenium compound contained in the raw material for thin film formation and other precursors, or the mixed solution in which the mixture is dissolved in an organic solvent, can be used as the raw material for thin film formation.

[0123] There are no particular limitations on the organic solvents used, and commonly known organic solvents can be used. Examples of such organic solvents include acetates such as ethyl acetate, butyl acetate, and methoxyethyl acetate; ethers such as tetrahydrofuran, tetrahydropyran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dibutyl ether, and dialkyl; ketones such as methyl butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl pentyl ketone, cyclohexanone, and methyl cyclohexanone; and hexane, cyclohexane, and cyclohexane. Hydrocarbons such as hexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, toluene, and xylene; hydrocarbons containing cyano groups such as 1-cyanopropane, 1-cyanobutane, 1-cyanohexane, cyanocyclohexane, cyanobenzene, 1,3-dicyanopropane, 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, and 1,4-dicyanobenzene; and pyridine, dimethylpyridine, etc. These organic solvents can be used alone or in mixtures of two or more, depending on the solubility of the solute, the operating temperature, boiling point, and ignition point.

[0124] When the above-mentioned raw material for thin film formation contains an organic solvent, from the viewpoint of easily forming a high-quality ruthenium metal thin film with low residual carbon content, it is preferable to adjust the total amount of the precursor in the raw material for thin film formation to be 0.01 mol / L to 2.0 mol / L, and more preferably to adjust it to be 0.05 mol / L to 1.0 mol / L.

[0125] Here, the total amount of precursors refers to the amount of the organorruthenium compound when the raw material for thin film formation does not contain any precursors other than the organorruthenium compound. When the raw material for thin film formation contains other precursors besides the organorruthenium compound, it refers to the total amount of the organorruthenium compound and the other precursors.

[0126] Furthermore, in the method for manufacturing the thin film of the present invention, the raw materials for forming the thin film may contain nucleophilic reagents as needed to improve the stability of the organorruthenium compound and other precursors. Examples of such nucleophilic reagents include, for instance, glycol ethers such as glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 18-crown ether-6, dicyclohexyl-18-crown ether-6, 24-crown ether-8, dicyclohexyl-24-crown ether-8, dibenzo-24-crown ether-8, ethylenediamine, N,N'-tetramethylethylenediamine, diethylenetriamine, triethylenetetramine, diethylenepentamine, pentaethylenehexamine, 1,1,4,7,7-pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine, etc. Polyamines such as triethoxytriethylamine, cyclic polyamines such as tetraazacyclotetradecane and tetraazacyclododecane, heterocyclic compounds such as pyridine, pyrrolidine, piperidine, morpholine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine, tetrahydrofuran, tetrahydrofuran, 1,4-dioxane, acetazole, thiazole, oxothiacyclopentane, β-keto esters such as methyl acetate, ethyl acetate, 2-methoxyethyl acetate, or β-diketones such as acetoacetone, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, and dipentacyclomethane. From the viewpoint of facilitating the adjustment of stability, the amount of these nucleophilic reagents used is preferably in the range of 0.1 mol to 10 mol, and more preferably in the range of 1 mol to 4 mol, relative to the total amount of the precursor.

[0127] The raw materials for thin film formation should, as far as possible, be free of impurity metallic elements, impurity halogens such as chlorine, and impurity organic components other than those constituting the raw materials. The content of impurity metallic elements is preferably 100 ppb or less per element, more preferably 10 ppb or less, and the total content is preferably 1 ppm or less, more preferably 100 ppb or less. Especially when used as gate insulating films, gate films, or barrier layers in LSI, the content of alkali metal elements and alkaline earth metal elements that affect the electrical properties of the resulting thin film must be reduced. The content of impurity halogens is preferably 100 ppm or less, more preferably 10 ppm or less, and even more preferably 1 ppm or less. The total content of impurity organic components is preferably 500 ppm or less, more preferably 50 ppm or less, and even more preferably 10 ppm or less. Furthermore, since moisture is a cause of particle generation in the raw materials for thin film formation or during thin film formation, it is advisable to remove moisture from precursors, organic solvents, and nucleophilic reagents as much as possible before use to reduce their respective moisture content. The water content of each of the precursor, organic solvent, and nucleophilic reagent is preferably below 10 ppm, and more preferably below 1 ppm. In the thin film manufacturing method of the present invention, since the impurity metal element composition, impurity halogen composition, impurity organic composition, and water content in the raw materials for thin film formation are set to values ​​below the above, it is easy to form a high-quality ruthenium thin film with low residual carbon content.

[0128] Furthermore, the raw materials for thin film formation are preferably as free of particles as possible in order to reduce or prevent particulate contamination of the formed thin film. Specifically, from the viewpoint of easily obtaining a uniform thin film, in the particle measurement of a liquid-phase light scattering type liquid particle detector, the number of particles larger than 0.3 μm is preferably 100 or less per 1 ml of the raw materials for thin film formation, and the number of particles larger than 0.2 μm is more preferably 100 or less per 1 ml of the raw materials for thin film formation.

[0129] The preferred method for manufacturing the thin film of the present invention is to perform a precursor film formation step and a thin film formation step in a film-forming chamber (hereinafter also referred to as a "deposition reaction section") in which a substrate is provided. Furthermore, the preferred method for manufacturing the thin film of the present invention includes, after the precursor film formation step, a step of venting undeposited precursor film forming material from the film-forming chamber (venting step 1). The preferred method for manufacturing the thin film of the present invention further includes, after the thin film formation step, a step of venting unreacted reactive material from the film-forming chamber (venting step 2). From the viewpoint of easily forming high-quality metallic ruthenium thin films with low ruthenium oxide content and low residual carbon content, it is preferable to repeatedly perform the precursor film formation step, venting step 1, the thin film formation step, and venting step 2.

[0130] Hereinafter, the steps of the method for manufacturing the thin film of the present invention will be described. <Precursor Thin Film Formation Step> The precursor thin film formation step is a step of forming a precursor thin film using a thin film forming raw material containing an organorruthenium compound. In this step, as a method for forming a precursor thin film using a thin film forming raw material, any method that can form a precursor thin film of the desired thickness is acceptable. For example, a method of depositing a raw material gas obtained by vaporizing a thin film forming raw material containing an organorruthenium compound on the surface of a substrate can be cited. More specifically, the raw material gas obtained by vaporizing the thin film forming raw material is introduced into a film forming chamber in which a substrate is provided, and the raw material gas is deposited on the surface of the substrate to form a precursor thin film.

[0131] As a method for introducing a raw material gas obtained by vaporizing the raw material for thin film formation into a film-forming chamber equipped with a substrate, as shown in Figures 1 and 3, there is a gas delivery method in which the raw material for thin film formation is vaporized into a raw material gas by heating and / or depressurizing the raw material container storing the raw material for thin film formation, and the raw material gas is introduced together with a carrier gas such as argon, nitrogen, or helium as needed into the film-forming chamber equipped with a substrate. There is also a liquid delivery method in which the raw material for thin film formation is vaporized in a liquid or solution state in a vaporization chamber, and the raw material for thin film formation is vaporized into a raw material gas by heating and / or depressurizing the vaporization chamber, and the raw material gas is introduced into the film-forming chamber equipped with a substrate. In the gas delivery method, the organorruthenium compound itself can be used as the raw material for thin film formation. In the liquid delivery method, a solution of the organorruthenium compound dissolved in an organic solvent or a solution of the organorruthenium compound can be used as the raw material for thin film formation. These raw materials for thin film formation may further include nucleophilic reagents, etc.

[0132] Furthermore, in addition to the gas delivery method and liquid delivery method described above, another method used in the precursor film formation step is the ALD method, which treats the aforementioned single-source method and mixed-source method as a multi-component system containing multiple precursors. However, from an operational point of view, it is preferable to vaporize the raw material for film formation in the range of 50°C to 200°C when using any of the introduction methods. Also, when the raw material for film formation is vaporized into a raw material gas in the raw material container or vaporization chamber, from the viewpoint of facilitating the vaporization of the raw material for film formation, the pressure in the raw material container or vaporization chamber is preferably 1 Pa to 10,000 Pa.

[0133] Examples of materials used for the substrate disposed in the film-forming chamber include silicon; ceramics such as silicon nitride, titanium nitride, tantalum nitride, titanium oxide, ruthenium oxide, zirconium oxide, hafnium oxide, and lanthanum oxide; glass; and metals such as cobalt and ruthenium. Examples of substrate shapes include plate-like, spherical, fibrous, and scaly. The surface of the substrate can be planar or a three-dimensional structure such as a trench structure.

[0134] After introducing the raw material gas into the film-forming chamber, the raw material gas is deposited on the surface of the substrate, thereby forming a precursor film on the substrate surface. When depositing the raw material gas on the substrate surface to form the precursor film, the substrate or the film-forming chamber can be heated. There are no particular limitations on the conditions for forming the precursor film; for example, the deposition temperature (substrate temperature) and the pressure in the film-forming chamber can be appropriately determined according to the type of raw material used for film formation. From the viewpoint of easily obtaining a uniform precursor film, the precursor film step is preferably performed by heating the substrate to 100°C or higher, more preferably by heating to 100°C to 450°C, and most preferably by heating to 150°C to 300°C. There are no particular limitations on the pressure in the film-forming chamber, but from the viewpoint of easily obtaining a uniform precursor film, it is preferably 1 Pa to 10,000 Pa, more preferably 10 Pa to 1,000 Pa.

[0135] <Exhaust Step 1> Exhaust Step 1 is the step of venting the film-forming material that has not been deposited on the surface of the substrate from the film-forming chamber. In Exhaust Step 1, ideally, the film-forming material (material gas) that has not been deposited on the surface of the substrate should be completely vented from the film-forming chamber, but complete venting is not necessary. As venting methods, examples include rinsing the film-forming chamber with inert gases such as helium, nitrogen, and argon, depressurizing the film-forming chamber to vent the gas, and combinations thereof. From the viewpoint of promoting the venting of the material gas, the depressurization rate when depressurizing the film-forming chamber is preferably in the range of 0.01 Pa to 300 Pa, and more preferably in the range of 0.01 Pa to 100 Pa.

[0136] <Thin Film Formation Step> The thin film formation step is the step of reacting the precursor thin film with the reactive material to form a metallic ruthenium thin film. Here, "reacting the precursor thin film with the reactive material" means reacting the organorruthenium compound contained in the precursor thin film with the compound represented by general formula (1) or the compound represented by general formula (2) contained in the reactive material.

[0137] In this step, for example, a method can be used to contact the precursor film with a reactive gas obtained by vaporizing the reactive material. By contacting the precursor film with the reactive gas, the precursor film reacts with the reactive gas, and a ruthenium film can be formed on the surface of the substrate. Specifically, after the exhaust step 1, the reactive gas is introduced into the film-forming chamber, and by the action of the reactive gas and the action of heat, the organic ruthenium compound contained in the precursor film reacts with the compound represented by general formula (1) or the compound represented by general formula (2) contained in the reactive gas, and a ruthenium film can be formed.

[0138] The reactive material used in the thin film forming step may contain any compound represented by general formula (1) or general formula (2), and may contain two or more compounds represented by general formula (1) or general formula (2), or may be a mixture of compounds represented by general formula (1) and general formula (2). The reactive gas obtained by vaporizing the reactive material may be mixed with a gas selected from the group consisting of argon, nitrogen, oxygen and hydrogen, as needed. Furthermore, to the extent that it does not adversely affect the effect of the present invention, the reactive gas may contain oxidizing gases such as oxygen, water vapor, and ozone, or reducing gases such as ammonia, hydrogen, monosilane, and hydrazine. From the viewpoint that the effect of the present invention is significant, the reactive material used in the thin film manufacturing method of the present invention is preferably a compound represented by general formula (1), and more preferably a compound represented by No. 43 or No. 135.

[0139] From the viewpoint of obtaining a high-quality ruthenium thin film with less residual carbon, the reaction temperature (substrate temperature) when reacting the precursor film with the reactive material is preferably 100°C or higher, more preferably 100°C to 450°C, particularly preferably 100°C to 300°C, and most preferably 150°C to 300°C. Furthermore, from the viewpoint of improving the reaction between the precursor film and the reactive gas, the pressure in the film-forming chamber during the film-forming step is preferably 1 Pa to 10,000 Pa, more preferably 10 Pa to 1,000 Pa.

[0140] <Exhaust Step 2> The thin film manufacturing method of the present invention aims to form a high-quality ruthenium metal thin film with low residual carbon content. Preferably, after the above-mentioned thin film formation step, an exhaust step 2 is provided to exhaust the reactive material not used in the formation of the ruthenium metal thin film. Specifically, after the thin film formation step in which the precursor film obtained in the thin film formation step reacts with the reactive gas obtained by vaporizing the aforementioned reactive material to form a ruthenium metal thin film on the surface of the substrate, an exhaust step 2 is preferably provided to exhaust the reactive material and by-product gas. More specifically, in the thin film formation step, after the formation of the ruthenium metal thin film, a step can be provided to exhaust the reactive gas that has not reacted with the surface of the precursor film and the by-product gas generated by the reaction between the precursor film and the reactive gas from the film formation chamber. In the exhaust step 2, ideally, the reactive gas and by-product gas are completely exhausted from the film formation chamber, but complete exhaust is not necessarily required. The exhaust method and the pressure reduction during depressurization can be set to be the same as in the exhaust step 1 described above.

[0141] The thin film forming step included in the thin film manufacturing method of the present invention is performed at least once, but may be performed more than twice until the ruthenium thin film reaches the desired thickness. That is, the above-mentioned thin film forming step may be performed more than twice to deposit two or more ruthenium thin films to form a thin film. For example, the above-mentioned thin film manufacturing method treats one of the preceding thin film forming step, the venting step 1, the thin film forming step, and the venting step 2 as one cycle, and the film thickness of the ruthenium thin film can be adjusted by adjusting the number of cycles.

[0142] As a specific example of the ALD apparatus used in the thin film manufacturing method of the present invention, as shown in FIG1, an apparatus can be used to heat and / or depressurize the raw material for thin film formation in the raw material container to vaporize it into a raw material gas, and supply the raw material gas together with a carrier gas as needed to the film forming chamber. Alternatively, as shown in FIG2, the raw material for thin film formation can be transported to the vaporization chamber in a liquid or solution state, and vaporized into a raw material gas by heating and / or depressurizing it in the vaporization chamber, and then supplied to the film forming chamber. Furthermore, the apparatus is not limited to the single-sheet apparatus with a film forming chamber shown in FIG1 and FIG2, but can also use an apparatus that can process multiple sheets simultaneously using a batch furnace.

[0143] Furthermore, in the method for manufacturing the thin film of the present invention, as shown in Figures 3 and 4, energy such as plasma, light, and voltage can be applied in the film-forming chamber, and a catalyst can also be used. There are no particular limitations on the timing of applying the energy and the timing of using the catalyst. For example, in the precursor film forming step, when the raw material gas is introduced into the film-forming chamber, or during heating when forming the precursor film; in the thin film forming step, when the reactive gas is introduced into the film-forming chamber, or when the precursor film reacts with the reactive gas; in the exhaust step 1 or exhaust step 2, the raw material gas, reactive gas, or by-product gas in the film-forming chamber can be exhausted, or it can be done between the above steps.

[0144] Furthermore, in the method for manufacturing the thin film of the present invention, in order to obtain a ruthenium thin film with better electrical properties, after the formation of the ruthenium thin film, annealing treatment can be performed in an inert environment, an oxidizing environment, or a reducing environment. If step filling is necessary, a reflow step can be provided. From the viewpoint of suppressing heat damage to the ruthenium thin film or the substrate, the temperature at this time is preferably 200°C to 1,000°C, and more preferably 250°C to 500°C.

[0145] The thin film manufactured by the thin film manufacturing method of the present invention can be coated onto substrates such as metals, oxide ceramics, nitride ceramics, and glass by appropriately selecting other precursors, reactive materials, and manufacturing conditions to become a thin film of the desired type. Because of its excellent electrical and optical properties, the thin film of the present invention can be widely used, for example, in the manufacture of electrode materials for memory devices such as DRAM devices, wiring materials for semiconductor devices, antimagnetic films used in the recording layer of hard disks, and catalyst materials for solid polymer fuel cells.

[0146] <Other> The following examples can be cited in this disclosure. [1] A reactive material containing a compound represented by the following general formula (1) or (2);

[0147]

[0148] (In formula (1), R1, R2, R3 and R4 each independently represent a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms or an electron-withdrawing group; the electron-withdrawing group is selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl and sulfomethyl; however, at least one of R1, R2, R3 and R4 represents an electron-withdrawing group).

[0149]

[0150] (In formula (2), R5 and R6 each independently represent a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms, or an electron-withdrawing group; the electron-withdrawing group is selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl, and sulfomethyl; however, at least one of R5 and R6 represents an electron-withdrawing group).

[0151] [2] The reactive material described in [1] is used to reduce organometallic compounds to metals.

[0152] [3] A method for manufacturing a thin film, comprising an atomic layer deposition process, using a reactive material as described in [1] or [2] to form a ruthenium thin film.

[0153] [4] The method for manufacturing a thin film as described in [3] includes: a step of forming a precursor film using a raw material for forming a thin film containing an organorruthenium compound; and a step of reacting the aforementioned precursor film with the aforementioned reactive material to form a metallic ruthenium film.

[0154] [5] The method for manufacturing a thin film as described in [4], wherein the aforementioned organorruthenium compound is selected from the group consisting of organorruthenium compounds represented by the following general formula (3), organorruthenium compounds represented by the following general formula (4) and organorruthenium compounds represented by the following general formula (5);

[0155]

[0156] (In formulas (3), (4) and (5), L1 represents a covalent ligand selected from the group consisting of aminoalkoxy, amidine, β-diketo, β-ketoimine, β-diketoimine, groups with a 2,4-pentadienyl structure and groups with a cyclopentadienyl structure, X represents a halogen atom, n represents an integer from 0 to 2, L2 represents an electron-donating ligand selected from the group consisting of carbonyl, cyano, trialkylphosphine compounds and isonitrile compounds, m represents an integer from 0 to 3, L3 represents an electron-donating ligand selected from the group consisting of chain diene compounds, cyclic diene compounds, chain polyene compounds and cyclic polyene compounds, y represents 1 or 2, L4 represents an electron-donating ligand containing aromatic compounds, z represents 0 or 1).

[0157] [6] The method for manufacturing a thin film as described in [4] or [5] involves depositing the vaporized raw material for forming the aforementioned thin film onto the surface of a substrate heated to 100°C to 450°C to form the aforementioned precursor thin film.

[0158] [7] The method for manufacturing a thin film as described in [6] further includes, after forming the aforementioned precursor thin film, a step of venting the undeposited raw material for forming the aforementioned thin film from the reaction system.

[0159] [8] The method for manufacturing a thin film as described in [7] further includes, after forming the aforementioned ruthenium thin film, a step of venting unreacted reactive material from the reaction system; and repeating the following steps: the step of forming a precursor film, the step of venting undeposited film forming raw material from the reaction system, the step of forming a ruthenium thin film, and the step of venting unreacted reactive material from the reaction system. Examples

[0160] Hereinafter, the present invention will be described in more detail by way of examples and comparative examples. However, the present invention is not limited to the following examples, etc.

[0161] [Example 1] Using an organorruthenium compound No. 303 as a raw material for thin film formation, a thin film was fabricated on a silicon wafer as a substrate using the ALD apparatus shown in Figure 1 under the following conditions and steps. The composition of the thin film was analyzed by X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a metallic ruthenium film, and the residual carbon content in the thin film was less than 0.1 atm%, which is less than the detection limit. Furthermore, the film thickness was measured by X-ray reflectance method, and the film formed on the substrate was a smooth film with a thickness of 1.6 nm, and the film thickness obtained per cycle was 0.008 nm.

[0162] (Conditions) Manufacturing method: ALD method Reaction temperature (substrate temperature): 220℃ Reactive gas: Gasifier of compound No. 43 (Steps) The series of steps (1) to (4) below are treated as 1 cycle and repeated for 200 cycles. (1) Under the conditions of raw material container temperature of 95℃ and raw material container pressure of 26.67Pa, the raw material gas obtained by vaporizing the raw material is introduced into the film forming chamber for 20 seconds, and the raw material gas is deposited on the surface of the substrate set in the film forming chamber. (2) The undeposited raw material gas is exhausted from the system by argon flushing for 10 seconds. (3) The reactive gas is introduced into the film forming chamber, and the precursor film reacts with the reactive gas for 1 second at a system pressure of 100Pa. (4) The unreacted reactive gas and by-product gas are exhausted from the system by argon flushing for 10 seconds.

[0163] [Example 2] Except that the reactive gas was changed to one that vaporizes compound No. 135, a thin film was manufactured using the same procedure as in Example 1. The composition of the thin film was analyzed using X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a ruthenium film, and the residual carbon content in the thin film was less than 0.1 atm%. Furthermore, the film thickness was measured using X-ray reflectance method, and the result showed that the film formed on the substrate was a smooth film with a thickness of 1.5 nm, and the film thickness obtained per cycle was 0.0075 nm.

[0164] [Comparative Example 1] The thin film was manufactured using the same procedure as in Example 1, except that the reactive gas was changed to oxygen. The composition of the thin film was analyzed by X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a mixture of ruthenium metal and ruthenium oxide, and the residual carbon content in the thin film was less than 0.1 atm%. In addition, the film thickness was measured by X-ray reflectance method, and the film formed on the substrate was a smooth film with a thickness of 1.8 nm, and the film thickness obtained per cycle was 0.009 nm.

[0165] [Comparative Example 2] Except for changing the reactive gas to hydrogen and the reaction temperature (substrate temperature) to 300°C, the thin film was manufactured using the same procedure as in Example 1. The composition of the thin film was analyzed using X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a ruthenium film with a residual carbon content of 4.5 atm%. Furthermore, the film thickness was measured using X-ray reflectance method, and the result showed that the film formed on the substrate was a smooth film with a thickness of 1.5 nm, and the film thickness obtained per cycle was 0.0075 nm.

[0166] [Example 3] Using the organorruthenium compound No. 306 as the raw material for thin film formation, a thin film was fabricated on a silicon wafer as the substrate using the ALD apparatus shown in Figure 1 under the following conditions and steps. The composition of the thin film was analyzed by X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a metallic ruthenium film, and the residual carbon content in the thin film was less than 0.1 atm%. Furthermore, the film thickness was measured by X-ray reflectance method, and the film formed on the substrate was a smooth film with a thickness of 1.8 nm, and the film thickness obtained per cycle was 0.009 nm.

[0167] (Conditions) Manufacturing method: ALD method Reaction temperature (substrate temperature): 230℃ Reactive gas: Gasifier of compound No. 43 (Steps) The series of steps (1) to (4) below are treated as 1 cycle and repeated for 200 cycles. (1) Under the conditions of raw material container temperature of 120℃ and raw material container pressure of 26.67 Pa, the raw material gas obtained by vaporizing the raw material is introduced into the film forming chamber at a system pressure of 26.67 Pa for 20 seconds, and the raw material gas is deposited on the surface of the substrate set in the film forming chamber. (2) The undeposited raw material gas is exhausted from the system by argon flushing for 10 seconds. (3) The reactive gas is introduced into the film forming chamber, and the precursor film reacts with the reactive gas at a system pressure of 100 Pa for 1 second. (4) The unreacted reactive gas and by-product gas are exhausted from the system by argon flushing for 10 seconds.

[0168] [Example 4] Except that the reactive gas was changed to one that vaporizes compound No. 135, the thin film reactive gas was manufactured using the same procedure as in Example 3. The composition of the thin film was analyzed using X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a ruthenium film, and the residual carbon content in the thin film was less than 0.1 atm%. Furthermore, the film thickness was measured using X-ray reflectance method, and the result showed that the film formed on the substrate was a smooth film with a thickness of 1.6 nm, and the film thickness obtained per cycle was 0.008 nm.

[0169] [Comparative Example 3] The thin film was manufactured using the same procedure as in Example 3, except that the reactive gas was changed to oxygen. The composition of the thin film was analyzed by X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a mixture of ruthenium metal and ruthenium oxide, and the residual carbon content in the thin film was less than 0.1 atm%. In addition, the film thickness was measured by X-ray reflectance method, and the film formed on the substrate was a smooth film with a thickness of 1.9 nm, and the film thickness obtained per cycle was 0.0095 nm.

[0170] [Comparative Example 4] Except for changing the reactive gas to hydrogen and the reaction temperature (substrate temperature) to 320°C, the thin film was manufactured using the same procedure as in Example 3. The composition of the thin film was analyzed using X-ray photoelectron spectroscopy, and the results confirmed that the thin film was a ruthenium film with a residual carbon content of 6.5 atm%. Furthermore, the film thickness was measured using X-ray reflectance method, and the result showed that the film formed on the substrate was a smooth film with a thickness of 1.3 nm, and the film thickness obtained per cycle was 0.0065 nm.

[0171] [Table 1] Organic Ru compound Reactive gases Components of the thin film Residual carbon content Example 1 No. 303 The vaporizer of compound No. 43 Metal ruthenium Less than 0.1 atm% Example 2 No. 303 The vaporizer of compound No. 135 Metal ruthenium Less than 0.1 atm% Example 3 No. 306 The vaporizer of compound No. 43 Metal ruthenium Less than 0.1 atm% Example 4 No. 306 The vaporizer of compound No. 135 Metal ruthenium Less than 0.1 atm% Comparative Example 1 No. 303 oxygen A mixture of metallic ruthenium and ruthenium oxide Less than 0.1 atm% Comparative Example 2 No. 303 hydrogen Metal ruthenium 4.5 atm% Comparative Example 3 No. 306 oxygen A mixture of metallic ruthenium and ruthenium oxide Less than 0.1 atm% Comparative Example 4 No. 306 hydrogen Metal ruthenium 6.5 atm%

[0172] The above results confirm that the thin film manufacturing method of the present invention is based on atomic layer deposition. By using reactive materials containing specific compounds, high-quality ruthenium metal thin films with low ruthenium oxide content and low residual carbon content can be manufactured at a low reaction temperature. Furthermore, in the thin film manufacturing method of the present invention, the film thickness obtained per cycle is significantly thick, thus implying that high productivity can be achieved. [Simplified Explanation of the Diagram]

[0026] [Figure 1] is a schematic diagram showing an example of an ALD apparatus used in the method for manufacturing the thin film of the present invention. [Figure 2] is a schematic diagram showing another example of an ALD apparatus used in the method for manufacturing the thin film of the present invention. [Figure 3] is a schematic diagram showing yet another example of an ALD apparatus used in the method for manufacturing the thin film of the present invention. [Figure 4] is a schematic diagram showing yet another example of an ALD apparatus used in the method for manufacturing the thin film of the present invention.

Claims

1. A method for manufacturing a thin film, comprising forming a ruthenium thin film using a reactive material containing a compound of the following general formula (1) or (2); (in formula (1), R1, R2, R3 and R4 each independently represent a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms, or an electron-withdrawing group; the electron-withdrawing group is selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl and sulfomethyl; however, at least one of R1, R2, R3 and R4 represents an electron-withdrawing group); (In formula (2), R5 and R6 each independently represent a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms, or an electron-withdrawing group; the electron-withdrawing group is selected from the group consisting of fluorine atom, chlorine atom, bromine atom, iodine atom, trifluoromethyl, trichloromethyl, tribromomethyl, triiodomethyl, cyano, aldehyde, acetyl, carboxyl, carboxymethyl, sulfonyl, and sulfomethyl; however, at least one of R5 and R6 represents an electron-withdrawing group).

2. The method for manufacturing a thin film as claimed in claim 1, comprising: a step of forming a precursor thin film using a thin film forming raw material containing an organorruthenium compound; and a step of reacting the aforementioned precursor thin film with the aforementioned reactive material to form a metallic ruthenium thin film.

3. The method for manufacturing the thin film as claimed in claim 2, wherein the aforementioned organorruthenium compound is selected from the group consisting of organorruthenium compounds represented by general formula (3), organorruthenium compounds represented by general formula (4), and organorruthenium compounds represented by general formula (5); (in formulas (3), (4), and (5), L1 represents the group consisting of aminoalkoxy, amidate, diketonate, ketoiminate, and diketiminate groups.) Group), covalently bonded ligands of groups consisting of 2,4-pentadienyl groups and cyclopentadienyl groups, where X represents a halogen atom, n represents an integer from 0 to 2, L2 represents an electron-donating ligand selected from the group consisting of carbonyl, cyano, trialkylphosphine, and isocyanide compounds, m represents an integer from 0 to 3, L3 represents an electron-donating ligand selected from the group consisting of chain dienes, cyclic dienes, chain polyenes, and cyclic polyenes, y represents 1 or 2, L4 represents an electron-donating ligand containing aromatic compounds, and z represents 0 or 1).

4. The method for manufacturing the thin film as claimed in claim 2, wherein the aforementioned precursor thin film is formed by depositing vaporized raw materials for thin film formation onto the surface of a substrate heated to 100°C to 450°C.

5. The method for manufacturing the thin film as claimed in claim 4, which, after forming the aforementioned precursor thin film, further includes a step of venting the undeposited raw materials for forming the aforementioned thin film from the reaction system.

6. The method for manufacturing the thin film as claimed in claim 5, which, after forming the aforementioned ruthenium thin film, further includes a step of venting the unreacted aforementioned reactive material from the reaction system; and repeatedly performs the following steps: the step of forming a precursor thin film, the step of venting the undeposited raw material for forming the thin film from the reaction system, the step of forming the ruthenium thin film, and the step of venting the unreacted reactive material from the reaction system.

Images