Compound, raw material for forming thin film, and method for producing thin film

Abstract

A compound represented by general formula (1) (in formula (1), R1-R4 each independently represent a hydrogen atom, an alkyl group having 1-5 carbon atoms, or the like, R5 and R6 each independently represent a hydrogen atom or an alkyl group having 1-5 carbon atoms, and M1 represents a gallium atom or an indium atom) or general formula (2) (in formula (2), R7-R10 each independently represent a hydrogen atom, an alkyl group having 1-5 carbon atoms, or the like, R11 represents a hydrogen atom or an alkyl group having 1-5 carbon atoms, and M2 represents a gallium atom or an indium atom).

Description

[Technical Field]

[0001] The present invention relates to a novel compound, a thin film-forming material containing the compound, and a method for producing a thin film using the thin film-forming material. [Background technology]

[0002] Thin film materials containing gallium or indium exhibit unique electrical properties and are applied to a wide variety of technologies, including oxide and nitride semiconductors used in LEDs, solar cells, and power semiconductor devices, electrode materials for memory elements, resistive films, diamagnetic films used in the recording layers of hard disks, and catalyst materials for polymer electrolyte fuel cells.

[0003] Examples of methods for manufacturing the above-mentioned thin films include sputtering, ion plating, metal organic decomposition (MOD) methods such as coating pyrolysis and sol-gel methods, and chemical vapor deposition. Among these, chemical vapor deposition (hereinafter sometimes simply referred to as "CVD") methods, including atomic layer deposition (ALD), are the most suitable manufacturing processes because they have many advantages such as excellent composition controllability and step coverage, suitability for mass production, and the ability to achieve hybrid integration.

[0004] A wide variety of raw materials have been reported as sources of gallium atoms and indium atoms used in chemical vapor deposition. For example, Patent Document 1 discloses triethylgallium as a raw material for producing a gallium nitride thin film, and Patent Document 2 discloses azidodialkylgallium. Furthermore, Patent Document 3 discloses dimethylgallium acetylacetonate as a dopant material for doping a zinc oxide film. Furthermore, Patent Document 4 discloses bistrimethylsilyldiethylindium as a raw material for producing an oxide film containing indium, and Patent Document 5 discloses ethylcyclopentadienylindium. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-149493 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-048886 [Patent Document 3] Special Publication No. 2010-502558 [Patent Document 4] Special Publication No. 2015-506416 [Patent Document 5] Japanese Patent Application Publication No. 2018-090855 Summary of the Invention [Problem to be solved by the invention]

[0006] In a method for forming a thin film by vaporizing a compound, such as a CVD method, the properties particularly required for the compound (precursor) used as a raw material are a low melting point (preferably being liquid at room temperature) and the ability to produce a high-quality thin film with good productivity. However, conventional gallium compounds and indium compounds used as raw materials for forming a thin film do not fully satisfy these requirements.

[0007] Therefore, an object of the present invention is to provide a gallium compound and an indium compound which have a lower melting point than conventional gallium compounds and indium compounds, and which, when used as a thin film forming raw material, can be used to produce high-quality thin films with good productivity. [Means for solving the problem]

[0008] As a result of extensive investigations, the present inventors have found that a gallium compound and an indium compound having a ligand with a specific structure can solve the above problems, and have arrived at the present invention.

[0009] That is, the present invention is a compound represented by the following general formula (1) or (2).

[0010] [ka]

[0011] (In the formula, R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a group represented by the following general formula (X-1), (X-2), or (X-3), and R 5 and R 6 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; M 1 represents a gallium atom or an indium atom. 1 ~R 6 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), some or all of the hydrogen atoms may be substituted with fluorine atoms.)

[0012] [ka]

[0013] (In the formula, R 21 ~R 23 each independently represents an alkyl group having 1 to 5 carbon atoms, and * represents a bond.

[0014] [ka]

[0015] (In the formula, R 7 ~R 10 each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a group represented by the following general formula (Y-1), (Y-2), or (Y-3), and R 11 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, M 2 represents a gallium atom or an indium atom. 7 and R 8 is a methyl group, R 11represents a hydrogen atom, a primary alkyl group having 1 to 5 carbon atoms, or a tertiary alkyl group having 4 to 5 carbon atoms. 7 ~R 11 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), some or all of the hydrogen atoms may be substituted with fluorine atoms.)

[0016] [ka]

[0017] (In the formula, R 24 ~R 26 each independently represents an alkyl group having 1 to 5 carbon atoms, and * represents a bond.

[0018] The present invention is a thin film-forming material containing the above compound.

[0019] The present invention also provides a method for producing a thin film, comprising the steps of: introducing a source gas obtained by vaporizing the thin film-forming source material into a treatment atmosphere in which a substrate is placed; and decomposing and / or chemically reacting the compound in the source gas to form a thin film containing gallium atoms or indium atoms on the surface of the substrate. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a gallium compound and an indium compound which have a lower melting point than conventional gallium compounds and indium compounds, and which, when used as a thin film forming material, can produce high-quality thin films with good productivity. The compound of the present invention is suitable as a thin film forming material for the CVD method, and in particular, since it has an ALD window, it can be preferably used as a thin film forming material for the ALD method. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram showing an example of an ALD apparatus used in the thin film manufacturing method according to the present invention. [Figure 2]FIG. 2 is a schematic diagram showing another example of an ALD apparatus used in the thin film manufacturing method according to the present invention. [Figure 3] FIG. 3 is a schematic diagram showing yet another example of an ALD apparatus used in the thin film manufacturing method according to the present invention. [Figure 4] FIG. 4 is a schematic diagram showing yet another example of an ALD apparatus used in the thin film manufacturing method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] The compound of the present invention is represented by the above general formula (1) or (2). The compound of the present invention is suitable as a precursor in a thin film manufacturing method having a vaporization step, such as the ALD method, which is a type of CVD method.

[0023] In the above general formula (1), R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a group represented by the above general formula (X-1), (X-2), or (X-3), and R 5 and R 6 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; M 1 represents a gallium atom or an indium atom. 1 ~R 6 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), some or all of the hydrogen atoms may be substituted with fluorine atoms.

[0024] Above R 1 ~R 6 Examples of the alkyl group having 1 to 5 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.

[0025] Above R 1 ~R 6In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), in which some or all of the hydrogen atoms have been substituted with fluorine atoms, examples include a fluoro group, a monofluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a trifluoroethyl group.

[0026] In the group represented by the above general formula (X-1), (X-2) or (X-3), R 21 ~R 23 each independently represents an alkyl group having 1 to 5 carbon atoms, and * represents a bond.

[0027] Above R 21 ~R 23 Examples of the alkyl group having 1 to 5 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.

[0028] In the above general formula (1), R 1 ~R 6 When used in a thin film manufacturing method that includes a step of vaporizing a compound, R is selected appropriately depending on the thin film manufacturing method to be applied. When used in a thin film manufacturing method that includes a step of vaporizing a compound, R is selected appropriately so as to obtain a compound with a high vapor pressure, a low melting point, and high thermal stability. 1 ~R 6 It is preferable to select

[0029] In view of the increased vapor pressure of the compound, R 1 and R 2 are each independently preferably an alkyl group having 1 to 3 carbon atoms or a group represented by (X-1), and more preferably a methyl group or a dimethylamino group. Similarly, from the viewpoint of increasing the vapor pressure of the compound, R 3 and R 4 are each independently preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. 5 and R 6are each independently preferably an alkyl group having 1 to 5 carbon atoms, more preferably a primary alkyl group having 1 to 5 carbon atoms. In addition, when used in a thin film manufacturing method using the MOD method, which does not involve a vaporization step, R 1 ~R 6 can be selected arbitrarily depending on the solubility in the solvent used, the thin film forming reaction, and the like.

[0030] In the above general formula (2), R 7 ~R 10 each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a group represented by the above general formula (Y-1), (Y-2), or (Y-3); R 11 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, M 2 represents a gallium atom or an indium atom. 7 and R 8 is a methyl group, R 11 represents a hydrogen atom, a primary alkyl group having 1 to 5 carbon atoms, or a tertiary alkyl group having 4 to 5 carbon atoms. 7 ~R 11 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), some or all of the hydrogen atoms may be substituted with fluorine atoms.

[0031] Above R 7 ~R 11 Examples of the alkyl group having 1 to 5 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.

[0032] Above R 7 ~R 11 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), in which some or all of the hydrogen atoms have been substituted with fluorine atoms, examples include a fluoro group, a monofluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a trifluoroethyl group.

[0033] In the group represented by the above general formula (Y-1), (Y-2) or (Y-3), R 24 ~R 26 each independently represents an alkyl group having 1 to 5 carbon atoms, and * represents a bond.

[0034] Above R 24 ~R 26 Examples of the alkyl group having 1 to 5 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.

[0035] In the above general formula (2), R 7 ~R 11 When used in a thin film manufacturing method that includes a step of vaporizing a compound, R is selected appropriately depending on the thin film manufacturing method to be applied. When used in a thin film manufacturing method that includes a step of vaporizing a compound, R is selected appropriately so as to obtain a compound with a high vapor pressure, a low melting point, and high thermal stability. 7 ~R 11 It is preferable to select

[0036] In view of the increased vapor pressure of the compound, R 7 and R 8 are each independently preferably an alkyl group having 1 to 3 carbon atoms or a group represented by (Y-1), and more preferably a methyl group or a dimethylamino group. Similarly, from the viewpoint of increasing the vapor pressure of the compound, R 9 and R 10 are each independently preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. 11 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a primary alkyl group having 1 to 5 carbon atoms. In addition, when used in a thin film manufacturing method using the MOD method, which does not involve a vaporization step, R 7 ~R 11 can be selected arbitrarily depending on the solubility in the solvent used, the thin film forming reaction, and the like.

[0037] In this specification, the compound represented by the above general formula (1) or (2) conceptually includes the compound represented by the following general formula (3) or (4).

[0038] [ka]

[0039] In the above general formula (3), R 1 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a group represented by the above general formula (X-1), (X-2), or (X-3), and R 5 and R 6 each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; M 1 represents a gallium atom or an indium atom. 1 ~R 6 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), some or all of the hydrogen atoms may be substituted with fluorine atoms.

[0040] [ka]

[0041] In the above general formula (4), R 7 ~R 10 each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a group represented by the above general formula (Y-1), (Y-2), or (Y-3); R 11 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, M 2 represents a gallium atom or an indium atom. 7 and R 8 is a methyl group, R 11 represents a hydrogen atom, a primary alkyl group having 1 to 5 carbon atoms, or a tertiary alkyl group having 4 to 5 carbon atoms. 7 ~R 11 In the alkyl group having 1 to 5 carbon atoms represented by the formula (I), some or all of the hydrogen atoms may be substituted with fluorine atoms.

[0042] Preferred specific examples of the compound represented by the general formula (1) include the following compounds No. 1 to No. 144. In the following compounds No. 1 to No. 144, "Me" represents a methyl group, "Et" represents an ethyl group, and "nPr" represents a normal propyl group.

[0043] [ka]

[0044] [ka]

[0045] [ka]

[0046] [ka]

[0047] [ka]

[0048] [ka]

[0049] [ka]

[0050] [ka]

[0051] The method for producing the compound represented by the general formula (1) is not particularly limited, and the compound can be produced by applying a known reaction. For example, a pentanediimine compound is reacted with an alkyllithium, lithium amide, lithium alkoxide, or trimethylsilyllithium in a toluene solvent, and then further reacted with gallium chloride or indium chloride to obtain an intermediate. The resulting intermediate is then reacted with an alkali lithium, filtered, the solvent is distilled off from the filtrate, and the resulting product is purified by distillation.

[0052] Preferred specific examples of the compound represented by general formula (2) include the following compounds Nos. 145 to 288. In the following compounds Nos. 145 to 288, "Me" represents a methyl group, "Et" represents an ethyl group, and "nPr" represents a normal propyl group.

[0053] [ka]

[0054] [ka]

[0055] [ka]

[0056] [ka]

[0057] [ka]

[0058] [ka]

[0059] [ka]

[0060] [ka]

[0061] The method for producing the compound represented by the general formula (2) is not particularly limited, and the compound can be produced by applying a known reaction. For example, an iminopentanone compound can be reacted with an alkali lithium, lithium amide, lithium alkoxide, or trimethylsilyllithium in a toluene solvent, followed by further reaction with gallium chloride or indium chloride to obtain an intermediate. The resulting intermediate can be reacted with an alkali lithium, filtered, the solvent removed from the filtrate, and then purified by distillation. Alternatively, the compound can be obtained by reacting an iminopentanone compound with a trialkylgallium or trialkylindium in a toluene solvent, followed by distillation of the solvent, followed by purification by distillation.

[0062] To ensure transportability in the piping of the apparatus used for producing the thin film, the compound of the present invention preferably has a melting point of less than 50° C., and more preferably is liquid at room temperature.

[0063] Next, the thin-film-forming raw material of the present invention will be described. The thin-film-forming raw material of the present invention contains a compound represented by the general formula (1) or (2) as a thin-film precursor. The form of the compound varies depending on the manufacturing process to which the thin-film-forming raw material is applied. For example, when manufacturing a thin film containing only gallium atoms or indium atoms as the metal, the thin-film-forming raw material of the present invention does not contain any metal compounds or metalloid compounds other than the compound represented by the general formula (1) or (2). On the other hand, when manufacturing a thin film containing two or more metals and / or metalloids, the thin-film-forming raw material of the present invention may contain, in addition to the compound represented by the general formula (1) or (2), a compound containing the desired metal and / or a compound containing a metalloid (hereinafter, sometimes referred to as "other precursors"). The thin-film-forming raw material of the present invention may further contain an organic solvent and / or a nucleophilic reagent, as described below. As explained above, the physical properties of the precursor compound represented by the general formula (1) or (2) are suitable for the CVD method, and therefore the thin-film-forming raw material of the present invention is useful as a chemical vapor deposition raw material (hereinafter, sometimes referred to as a "CVD raw material"). In particular, the compound represented by the above general formula (1) or (2) has an ALD window, and therefore the thin film-forming material of the present invention is particularly suitable for the ALD method.

[0064] When the thin film forming material of the present invention is a material for chemical vapor deposition, its form is appropriately selected depending on the method of transportation and supply in the CVD method used.

[0065] The transport and supply methods include a gas transport method in which the CVD raw material is vaporized by heating and / or reducing the pressure in a container (hereinafter sometimes referred to as the "raw material container") in which the raw material is stored to form a raw material gas, and then introduced into a deposition chamber (hereinafter sometimes referred to as the "deposition reaction section") containing a substrate, along with an optional carrier gas such as argon, nitrogen, or helium. Another method is a liquid transport method in which the CVD raw material is transported in a liquid or solution state to a vaporization chamber, where it is vaporized by heating and / or reducing the pressure in the vaporization chamber to form a raw material gas, and then introduced into the deposition chamber. In the gas transport method, the compound represented by the general formula (1) or (2) itself can be used as the CVD raw material. In the liquid transport method, the compound represented by the general formula (1) or (2) itself or a solution of the compound dissolved in an organic solvent can be used as the CVD raw material. These CVD raw materials may further contain other precursors, nucleophilic reagents, etc.

[0066] Multi-component CVD methods include a method in which each component of the CVD raw material is vaporized and supplied independently (hereinafter sometimes referred to as the "single source method"), and a method in which a mixed raw material in which multiple raw materials are mixed in advance to a desired composition is vaporized and supplied (hereinafter sometimes referred to as the "cocktail source method"). In the cocktail source method, the CVD raw material can be a mixture of the compound represented by the above general formula (1) or (2) and another precursor, or a mixed solution in which the mixture is dissolved in an organic solvent. This mixture or mixed solution may further contain a nucleophilic reagent, etc.

[0067] The organic solvent is not particularly limited, and any well-known organic solvent can be used. Examples of the organic solvent 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 dioxane; ketones such as methyl butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, and methylcyclohexanone; hydrocarbons such as hexane, cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, toluene, and xylene; hydrocarbons having a cyano group such as 1-cyanopropane, 1-cyanonobutane, 1-cyanohexane, cyanocyclohexane, cyanobenzene, 1,3-dicyanopropane, 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, and 1,4-dicyanobenzene; pyridine, lutidine, and the like. These organic solvents may be used alone or in combination of two or more depending on the solubility of the solute, the relationship between the temperature used and the boiling point, the flash point, and the like.

[0068] When the thin film-forming raw material of the present invention is a mixed solution with the above-mentioned organic solvent, the total amount of precursors in the thin film-forming raw material is preferably 0.01 mol / L to 2.0 mol / L, and more preferably 0.05 mol / L to 1.0 mol / L.

[0069] Here, the total amount of precursors means the amount of the compound represented by the general formula (1) or (2) when the thin film-forming raw material of the present invention does not contain any metal compounds or semimetal compounds other than the compound represented by the general formula (1) or (2) above, and means the total amount of the compound represented by the general formula (1) or (2) above and the other precursors when the thin film-forming raw material of the present invention contains, in addition to the compound represented by the general formula (1) or (2), compounds containing other metals and / or compounds containing semimetals (other precursors).

[0070] In the case of a multi-component CVD method, other precursors used together with the compound represented by the general formula (1) or (2) above are not particularly limited, and well-known general precursors used as CVD raw materials can be used.

[0071] Examples of the other precursors include compounds of silicon or a metal with one or more compounds selected from the group consisting of compounds used as organic ligands, such as alcohol compounds, glycol compounds, β-diketone compounds, cyclopentadiene compounds, and organic amine compounds. Examples of the metal species of the precursor include lithium, sodium, potassium, magnesium, calcium, strontium, barium, titanium, zirconium, hafnium, vanadium, tantalum, chromium, molybdenum, tungsten, manganese, iron, cobalt, rhodium, iridium, nickel, palladium, platinum, copper, silver, gold, zinc, aluminum, germanium, tin, lead, antimony, bismuth, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, ruthenium, and lutetium.

[0072] Examples of alcohol compounds that can be used as organic ligands for the other precursors include alkyl alcohols such as methanol, ethanol, propanol, isopropyl alcohol, butanol, sec-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, pentyl alcohol, isopentyl alcohol, and tert-pentyl alcohol; 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; ether alcohols such as 2-(2-methoxyethoxy)-1,1-dimethylethanol, 2-propoxy-1,1-diethylethanol, 2-s-butoxy-1,1-diethylethanol, and 3-methoxy-1,1-dimethylpropanol; and 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.

[0073] Examples of glycol compounds that can be used as organic ligands for the other precursors include 1,2-ethanediol, 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.

[0074] Examples of β-diketone compounds that can be used as organic ligands for the other precursors include acetylacetone, 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, 2,9-dimethylnonane-4,6-dione, and 2-methyl-6- Examples of suitable fluorine-substituted alkyl β-diketones include ethyldecane-3,5-dione and 2,2-dimethyl-6-ethyldecane-3,5-dione; fluorine-substituted alkyl β-diketones such as 1,1,1-trifluoropentane-2,4-dione, 1,1,1-trifluoro-5,5-dimethylhexane-2,4-dione, 1,1,1,5,5,5-hexafluoropentane-2,4-dione and 1,3-diperfluorohexylpropane-1,3-dione; and ether-substituted β-diketones such as 1,1,5,5-tetramethyl-1-methoxyhexane-2,4-dione, 2,2,6,6-tetramethyl-1-methoxyheptane-3,5-dione and 2,2,6,6-tetramethyl-1-(2-methoxyethoxy)heptane-3,5-dione.

[0075] Examples of cyclopentadiene compounds that can be used as organic ligands for the other precursors include cyclopentadiene, methylcyclopentadiene, ethylcyclopentadiene, propylcyclopentadiene, isopropylcyclopentadiene, butylcyclopentadiene, sec-butylcyclopentadiene, isobutylcyclopentadiene, tert-butylcyclopentadiene, dimethylcyclopentadiene, and tetramethylcyclopentadiene.

[0076] Examples of organic amine compounds that can be used as organic ligands for the other precursors include methylamine, ethylamine, propylamine, isopropylamine, butylamine, sec-butylamine, tert-butylamine, isobutylamine, dimethylamine, diethylamine, dipropylamine, diisopropylamine, ethylmethylamine, propylmethylamine, and isopropylmethylamine.

[0077] The above-mentioned other precursors are known in the art, and their production methods are also known. For example, when an alcohol compound is used as the organic ligand, the precursor can be produced by reacting the inorganic salt of the metal or a hydrate thereof described above with an alkali metal alkoxide of the alcohol compound. Examples of the inorganic salt of the metal or a hydrate thereof include metal halides and nitrates, and examples of the alkali metal alkoxide include sodium alkoxide, lithium alkoxide, and potassium alkoxide.

[0078] In the case of the single-source method, it is preferable to use, as the other precursor, a compound whose thermal decomposition and / or oxidative decomposition behavior is similar to that of the compound represented by the general formula (1) or (2).In the case of the cocktail-source method, it is preferable to use, as the other precursor, a compound whose thermal decomposition and / or oxidative decomposition behavior is similar to that of the compound represented by the general formula (1) or (2), and which does not undergo changes that impair the desired properties of the precursor due to chemical reactions, etc., during mixing.

[0079] Furthermore, the thin film-forming raw material of the present invention may contain a nucleophilic reagent, if necessary, to impart stability to the compound represented by the general formula (1) or (2) and other precursors. Examples of the nucleophilic reagent include ethylene glycol ethers such as glyme, diglyme, triglyme, and tetraglyme; crown ethers such as 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8, and dibenzo-24-crown-8; ethylenediamine, N,N'-tetramethylethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4,7,7-pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine; and triethylenetetramine. Examples of suitable nucleophilic reagents include polyamines such as ethoxytriethyleneamine, cyclic polyamines such as cyclam and cyclen, heterocyclic compounds such as pyridine, pyrrolidine, piperidine, morpholine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, oxazole, thiazole, and oxathiolane, β-ketoesters such as methyl acetoacetate, ethyl acetoacetate, and 2-methoxyethyl acetoacetate, and β-diketones such as acetylacetone, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, and dipivaloylmethane. The amount of these nucleophilic reagents used is preferably 0.1 to 10 moles, and more preferably 1 to 4 moles, per mole of the total amount of precursor.

[0080] The thin-film-forming raw material of the present invention is intended to contain as little impurity metal elements, impurity halogens such as impurity chlorine, and impurity organic components as possible, other than the components constituting the thin film. The impurity metal element content 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. In particular, when used as a gate insulating film, gate film, or barrier layer for an LSI, it is necessary to reduce the content of alkali metal elements and alkaline earth metal elements, which affect the electrical properties of the resulting thin film. The impurity halogen content is preferably 100 ppm or less, more preferably 10 ppm or less, and most 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 most preferably 10 ppm or less. Furthermore, since moisture can cause particle generation in chemical vapor deposition raw materials and during thin-film formation, it is preferable to remove as much moisture as possible from precursors, organic solvents, and nucleophilic reagents before use. The water content of each of the precursor, organic solvent and nucleophilic reagent is preferably 10 ppm or less, more preferably 1 ppm or less.

[0081] Furthermore, in order to reduce or prevent particle contamination of the thin film to be formed, it is preferable that the thin film-forming raw material of the present invention contains as few particles as possible. Specifically, in particle measurement in the liquid phase using a light scattering liquid-borne particle detector, the number of particles larger than 0.3 μm per mL of liquid phase is preferably 100 or less, the number of particles larger than 0.2 μm per mL of liquid phase is more preferably 1,000 or less, and the number of particles larger than 0.2 μm per mL of liquid phase is most preferably 100 or less.

[0082] Next, a method for producing a thin film using the thin film-forming raw material of the present invention will be described. The thin film production method of the present invention is a CVD method in which a raw material gas obtained by vaporizing the thin film-forming raw material of the present invention, and a reactive gas used as needed, are introduced into a film-forming chamber (processing atmosphere) in which a substrate is placed, and then precursors in the raw material gas are decomposed and / or chemically reacted on the substrate to grow and deposit a thin film containing gallium atoms or indium atoms on the substrate surface. There are no particular limitations on the raw material transport / supply method, deposition method, production conditions, production equipment, etc., and well-known conditions and methods can be used.

[0083] Examples of the reactive gases used as needed include reducing gases such as hydrogen, oxidizing gases such as oxygen, ozone, and water vapor, organic amine compounds such as monoalkylamines, dialkylamines, trialkylamines, and alkylenediamines, and nitriding gases such as hydrazine and ammonia. These reactive gases may be used alone or in combination of two or more. The compounds represented by the general formula (1) or (2) above have the property of reacting particularly well with ammonia or ozone. Therefore, it is preferable to use ammonia or ozone as the reactive gas.

[0084] The above-mentioned transportation and supply method may include the gas transportation method, liquid transportation method, single source method, cocktail source method, etc.

[0085] Examples of the deposition method include thermal CVD, which deposits a thin film by reacting a source gas or a source gas with a reactive gas using only heat; plasma CVD, which uses heat and plasma; photo-CVD, which uses heat and light; photo-plasma CVD, which uses heat, light, and plasma; and ALD, which separates the CVD deposition reaction into elementary processes and deposits in stages at the molecular level.

[0086] Examples of materials for the substrate include silicon; ceramics such as silicon nitride, titanium nitride, tantalum nitride, titanium oxide, titanium nitride, ruthenium oxide, zirconium oxide, hafnium oxide, and lanthanum oxide; glass; and metals such as metallic cobalt. The substrate may have a plate-like, spherical, fibrous, or scale-like shape. The substrate surface may be flat or may have a three-dimensional structure such as a trench structure.

[0087] The production conditions include the reaction temperature (substrate temperature), reaction pressure, deposition rate, etc. The reaction temperature is preferably 100°C or higher, at which the compound of the present invention reacts sufficiently, more preferably 150°C to 400°C, and particularly preferably 200°C to 350°C. The reaction pressure is preferably 10 Pa to atmospheric pressure in the case of thermal CVD or photo-CVD, and preferably 10 Pa to 2,000 Pa in the case of using plasma.

[0088] The deposition rate can be controlled by the raw material supply conditions (vaporization temperature, vaporization pressure), reaction temperature, and reaction pressure. A high deposition rate can deteriorate the properties of the resulting thin film, while a low rate can cause productivity problems. Therefore, the deposition rate is preferably 0.01 nm / min to 100 nm / min, and more preferably 1 nm / min to 50 nm / min. In the case of the ALD method, the deposition rate is controlled by the number of cycles to obtain the desired film thickness.

[0089] Further, the above-mentioned production conditions include the temperature and pressure when the thin film forming raw material is vaporized to form a raw material gas. The step of vaporizing the thin film forming raw material to form a raw material gas may be carried out in a raw material container or in a vaporization chamber. In either case, the thin film forming raw material of the present invention is preferably evaporated at 0°C to 150°C. Furthermore, when the thin film forming raw material is vaporized in a raw material container or in a vaporization chamber to form a raw material gas, the pressure in both the raw material container and the vaporization chamber is preferably 1 Pa to 10,000 Pa.

[0090] The thin film manufacturing method of the present invention employs the ALD method and includes a raw material introduction step of vaporizing thin film-forming raw materials to form a raw material gas by the above-described transport and supply method and introducing the raw material gas into a film formation chamber, as well as a precursor thin film formation step of forming a precursor thin film on the surface of the substrate using the above-described compound in the raw material gas, an exhaust step of exhausting unreacted compound gas, and a metal-containing thin film formation step of chemically reacting the precursor thin film with a reactive gas to form a metal-containing thin film on the surface of the substrate.

[0091] Each step of the ALD method is described in detail below, taking the formation of a metal thin film as an example. First, the raw material introduction step described above is performed. The preferred temperature and pressure when using the thin film-forming raw materials as raw material gases are the same as those described for the thin film production method using the CVD method. Next, the raw material gas introduced into the film formation chamber is brought into contact with the surface of the substrate, thereby forming a precursor thin film on the substrate surface (precursor thin film formation step). At this time, heat may be applied by heating the substrate or the film formation chamber. The precursor thin film formed in this step is a thin film formed from a compound represented by the above general formula (1) or (2), or a thin film formed by partial decomposition and / or reaction of a compound represented by the above general formula (1) or (2), and has a composition different from that of the target metal nitride thin film. The substrate temperature during this step is preferably room temperature to 500°C, more preferably 150°C to 350°C. The pressure of the system (in the film formation chamber) during this step is preferably 1 Pa to 10,000 Pa, more preferably 10 Pa to 1,000 Pa.

[0092] Next, unreacted compound gases and by-product gases are exhausted from the film formation chamber (exhaust process). Ideally, unreacted compound gases and by-product gases are completely exhausted from the film formation chamber, but complete exhaust is not necessarily required. Exhaust methods include purging the system with an inert gas such as nitrogen, helium, or argon, exhausting by reducing the pressure inside the system, and a combination of these. When reducing the pressure, the degree of vacuum is preferably 0.01 Pa to 300 Pa, and more preferably 0.01 Pa to 100 Pa.

[0093] Next, a nitriding gas is introduced into the deposition chamber as a reactive gas, and a metal thin film is formed from the precursor thin film obtained in the previous precursor thin film formation step by the action of the nitriding gas or the action of the nitriding gas and heat (metal-containing thin film formation step). When heat is applied in this step, the temperature is preferably room temperature to 500°C, more preferably 150 to 350°C. The pressure of the system (inside the deposition chamber) when this step is performed is preferably 1 Pa to 10,000 Pa, more preferably 10 Pa to 1,000 Pa. The compound represented by the above general formula (1) or (2) has good reactivity with the nitriding gas, and therefore a high-quality metal thin film with a low residual carbon content can be obtained.

[0094] In the thin film manufacturing method of the present invention, when the ALD method is employed as described above, thin film deposition by a series of operations consisting of the raw material introduction step, precursor thin film formation step, evacuation step, and metal-containing thin film formation step is considered as one cycle, and this cycle may be repeated multiple times until a thin film of the required thickness is obtained. In this case, after one cycle is performed, it is preferable to evacuate the unreacted compound gas, reactive gas, and by-product gas from the deposition reaction zone in the same manner as in the evacuation step, and then perform the next cycle.

[0095] Furthermore, in forming a metal thin film by the ALD method, energy such as plasma, light, or voltage may be applied, or a catalyst may be used. The timing of applying the energy and using the catalyst is not particularly limited, and may be, for example, when introducing a compound gas in the raw material introduction step, when heating in the precursor thin film formation step or the metal-containing thin film formation step, when evacuating the system in the evacuation step, when introducing a reducing gas in the metal-containing thin film formation step, or between the steps.

[0096] In the thin film manufacturing method of the present invention, after the thin film deposition, annealing may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere to obtain better electrical properties, and a reflow step may be performed if step filling is required. In this case, the temperature is 200°C to 1,000°C, and preferably 250°C to 500°C.

[0097] Well-known ALD equipment can be used in the thin film manufacturing method of the present invention. Specific examples of ALD equipment include an equipment capable of supplying a precursor by bubbling, as shown in Figures 1 and 3, and an equipment having a vaporization chamber, as shown in Figures 2 and 4. Also included are equipment capable of performing plasma treatment on a reactive gas, as shown in Figures 3 and 4. It should be noted that the present invention is not limited to single-wafer processing equipment equipped with a film-forming chamber (hereinafter referred to as a "deposition reaction section") as shown in Figures 1 to 4, and an equipment capable of simultaneously processing multiple wafers using a batch furnace can also be used. These can also be used as CVD equipment.

[0098] Thin films produced using the thin-film-forming material of the present invention can be formed into desired types of thin films, such as metals, oxide ceramics, nitride ceramics, and glasses, by appropriately selecting other precursors, reactive gases, and production conditions. These thin films are known to exhibit electrical and optical properties and have been used in a variety of applications. Examples include metal gallium thin films, metal indium thin films, gallium oxide thin films, indium oxide thin films, gallium nitride thin films, indium nitride thin films, gallium alloys, indium alloys, gallium-containing composite oxide thin films, and indium-containing composite oxide thin films. Gallium alloys include Ga-Fe alloys, Ga-Sn alloys, Ga-Zn alloys, and Ga-In alloys. Indium alloys include In-Sn alloys, In-Zn alloys, In-P alloys, and In-Ga alloys. These thin films are widely used, for example, in the production of electrode materials for memory elements, such as DRAM elements, resistive films, diamagnetic films used in hard disk recording layers, and catalyst materials for polymer electrolyte fuel cells. [Example]

[0099] The present invention will be described in more detail below with reference to examples, comparative examples and evaluation examples, but the present invention is not limited to the following examples.

[0100] <Production of Gallium Compounds> The following Examples 1 to 4 show the results of producing gallium compounds.

[0101] [Example 1] Preparation of Compound No. 5 Under an Ar atmosphere, 5.70 g (0.037 mol) of N,N-diethyl-2,4-pentanediimine and 50 mL of dehydrated toluene were added to a 100 mL two-neck flask and cooled to -20°C. 24 mL of an n-hexane solution containing n-butyllithium (n-butyllithium content: 1.58 mol / L) was added dropwise, and the mixture was warmed to room temperature and stirred for 2 hours. 6.51 g (0.037 mol) of gallium chloride and 70 mL of dehydrated toluene were added to a separate 200 mL four-neck flask and cooled to -20°C. The previously prepared solution was added dropwise to the mixture, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction mixture was filtered, and the solvent was distilled off under slightly reduced pressure. Intermediate 1 was obtained in a yield of 6.81 g by vacuum distillation. A 100 mL two-neck flask was charged with 6.81 g (0.023 mol) of intermediate 1 and 50 mL of dehydrated toluene and cooled to -20°C. 40 mL of a diethyl ether solution containing methyllithium (methyllithium content: 1.17 mol / L) was added dropwise, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction solution was filtered, and the solvent was distilled off under slightly reduced pressure. 2.75 g (47% yield) of the target product was obtained as a pale yellow liquid by vacuum distillation.

[0102] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (-0.02:s:6)(0.95:t:6)(1.57:s:6)(3.03:q:4)(4.29:s:1) (2) Elemental analysis (metal analysis: ICP-AES) Ga: 27.7% by mass, C: 52.8% by mass, H: 8.7% by mass, N: 10.8% by mass (Theoretical value; Ga: 27.56% by mass, C: 52.21% by mass, H: 9.16% by mass, N: 11.07% by mass)

[0103] [Example 2] Preparation of Compound No. 8 Under an Ar atmosphere, 10.4 g (0.057 mol) of N,N-dipropyl-2,4-pentanediimine and 90 mL of dehydrated toluene were added to a 200 mL four-neck flask and cooled to -20°C. 36 mL of an n-hexane solution containing n-butyllithium (n-butyllithium content: 1.58 mol / L) was added dropwise, and the mixture was warmed to room temperature and stirred for 2 hours. 10.0 g (0.057 mol) of gallium chloride and 120 mL of dehydrated toluene were added to a separate 300 mL four-neck flask and cooled to -20°C. The previously prepared solution was added dropwise to the mixture, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction solution was filtered, and the solvent was distilled off under slightly reduced pressure. Intermediate 2 was obtained in a yield of 13.1 g by vacuum distillation. A 100 mL two-neck flask was charged with 5.03 g (0.016 mol) of intermediate 2 and 35 mL of dehydrated toluene and cooled to -20°C. 27 mL of a diethyl ether solution containing methyllithium (methyllithium content: 1.17 mol / L) was added dropwise, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction solution was filtered, and the solvent was distilled off under slightly reduced pressure. The target product was obtained as a pale yellow liquid in 3.19 g (73% yield) by vacuum distillation.

[0104] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (-0.01:s:6)(0.71:t:6)(1.46:sext:4)(1.61:s:6)(3.00~3.04:m:4)(4.33:s:1) (2) Elemental analysis (metal analysis: ICP-AES) Ga: 24.9% by mass, C: 55.7% by mass, H: 9.4% by mass, N: 10.0% by mass (Theoretical value; Ga: 24.80 mass%, C: 55.55 mass%, H: 9.68 mass%, N: 9.97 mass%)

[0105] [Example 3] Preparation of Compound No. 44 Under an Ar atmosphere, 7.03 g (0.022 mol) of Intermediate 2 described in Example 2 and 35 mL of anhydrous toluene were placed in a 200 mL four-neck flask and cooled to -20°C. 20 mL of anhydrous toluene solution containing 2.62 g (0.046 mol) of lithium dimethylamide was added dropwise, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction solution was filtered, and the solvent was distilled off under slightly reduced pressure. 2.44 g (33% yield) of the target product was obtained as a pale yellow liquid by vacuum distillation.

[0106] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (0.78:t:6)(1.55~1.61:m:4)(1.62:s:6)(2.97:s:12)(3.13~3.17:m:4)(4.29:s:1) (2) Elemental analysis (metal analysis: ICP-AES) Ga: 20.7% by mass, C: 53.3% by mass, H: 9.5% by mass, N: 16.5% by mass (Theoretical value; Ga: 20.56% by mass, C: 53.12% by mass, H: 9.81% by mass, N: 16.52% by mass)

[0107] [Example 4] Preparation of Compound No. 152 Under an Ar atmosphere, 16.3 g (0.115 mol) of N-propyl-4-imino-2-pentanone and 120 mL of dehydrated toluene were added to a 300 mL four-neck flask and cooled to -20 °C. 73 mL of an n-hexane solution containing n-butyllithium (n-butyllithium content: 1.58 mol / L) was added dropwise, and the mixture was warmed to room temperature and stirred for 2 hours. 19.8 g (0.112 mol) of gallium chloride and 230 mL of dehydrated toluene were added to a separate 1 L four-neck flask and cooled to -20 °C. The previously prepared solution was added dropwise to the mixture, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction mixture was filtered, and the solvent was removed by distillation under slightly reduced pressure to obtain intermediate 3 in a crude yield of 26.4 g. A 100 mL two-neck flask was charged with 6.04 g (0.021 mol) of intermediate 3 and 45 mL of dehydrated toluene and cooled to -20°C. 37 mL of a diethyl ether solution containing methyllithium (methyllithium content: 1.17 mol / L) was added dropwise, and the mixture was warmed to room temperature and stirred for 18 hours. The reaction solution was filtered, and the solvent was distilled off under slightly reduced pressure. 2.41 g (47% yield) of the target product was obtained as a pale yellow liquid by vacuum distillation.

[0108] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (0.04:s:6)(0.58:t:3)(1.26~1.32:m:2)(1.32:s:3)(1.85:s:3)(2.79~2.83:m:2)(4.63:s:1) (2) Elemental analysis (metal analysis: ICP-AES) Ga: 29.1% by mass, C: 50.3% by mass, H: 8.2% by mass, N: 5.8% by mass, O: 6.6% by mass (Theoretical value; Ga: 29.04 mass%, C: 50.05 mass%, H: 8.40 mass%, N: 5.84 mass%, O: 6.67 mass%)

[0109] <Production of indium compounds> The following Examples 5 to 7 show the results of producing indium compounds.

[0110] [Example 5] Preparation of Compound No. 77 Under an Ar atmosphere, 3.51 g (0.022 mol) of trimethylindium and 40 mL of dehydrated toluene were added to a 100 mL two-neck flask. 3.38 g (0.022 mol) of N,N-diethyl-2,4-pentanediimine was added dropwise, and the mixture was stirred at room temperature for 18 hours. The solvent was removed by distillation under slightly reduced pressure, and the target product was obtained as a yellow liquid in an amount of 5.60 g (86% yield).

[0111] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (0.06:s:6)(0.97:t:6)(1.63:s:6)(3.02:q:4)(4.27:s:1) (2) Elemental analysis (metal analysis: ICP-AES) In: 38.4% by mass, C: 44.7% by mass, H: 7.9% by mass, N: 9.0% by mass (Theoretical value; In: 38.50% by mass, C: 44.32% by mass, H: 7.78% by mass, N: 9.40% by mass)

[0112] [Example 6] Preparation of Compound No. 80 Under an Ar atmosphere, 3.01 g (0.019 mol) of trimethylindium and 40 mL of dehydrated toluene were added to a 100 mL two-neck flask. 3.44 g (0.019 mol) of N,N-dipropyl-2,4-pentanediimine was added dropwise, and the mixture was stirred at room temperature for 18 hours. The solvent was removed by distillation under slightly reduced pressure, and the target product was obtained as a yellow liquid in an amount of 4.68 g (76% yield).

[0113] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (0.07:s:6)(0.71:t:6)(1.46:sext:4)(1.68:s:6)(3.01~3.04:m:4)(4.30:s:1) (2) Elemental analysis (metal analysis: ICP-AES) In: 35.2% by mass, C: 48.1% by mass, H: 8.1% by mass, N: 8.6% by mass (Theoretical value; In: 35.20% by mass, C: 47.87% by mass, H: 8.34% by mass, N: 8.59% by mass)

[0114] [Example 7] Preparation of Compound No. 224 Under an Ar atmosphere, 3.02 g (0.019 mol) of trimethylindium and 40 mL of dehydrated toluene were added to a 100 mL two-neck flask. 2.69 g (0.019 mol) of N-propyl-4-imino-2-pentanone was added dropwise, and the mixture was stirred at room temperature for 18 hours. The solvent was removed by distillation under slightly reduced pressure, and the target product was obtained as a pale yellow solid (melting point 44°C) in a yield of 4.47 g (84%) by vacuum distillation.

[0115] (Analysis value) (1) 1 H NMR (solvent: deuterated benzene) (chemical shift: multiplicity: hydrogen number) (0.07:s:6)(0.58:t:3)(1.22~1.32:m:2)(1.41:s:3)(1.95:s:3)(2.77~2.81:m:2)(4.67:s:1) (2) Elemental analysis (metal analysis: ICP-AES) In: 40.3% by mass, C: 42.3% by mass, H: 6.9% by mass, N: 4.8% by mass, O: 5.7% by mass (Theoretical values; In: 40.28% by mass, C: 42.13% by mass, H: 7.07% by mass, N: 4.91% by mass, O: 5.61% by mass)

[0116] [Evaluation example] The compounds of the present invention obtained in Examples 1 to 4 and the following comparative compound 1 were evaluated as follows. (1) Melting point evaluation The state of the compounds at 20° C. was observed visually. For those that were solid at 20° C., the melting points were measured using a micro melting point measuring device. The results are shown in Table 1. (2) Temperature (°C) at 50% mass loss in atmospheric pressure TG-DTA Using TG-DTA, measurements were performed under atmospheric pressure with an Ar flow rate of 100 mL / min, a heating rate of 10°C / min, and a scanning temperature range of 30°C to 600°C. The temperature (°C) at which the weight of the test compound decreased by 50% by mass was evaluated as the "temperature (°C) at which the weight of the test compound decreased by 50% by mass using TG-DTA at atmospheric pressure" The results are shown in Table 1. (3) Temperature (°C) at 50% mass loss in reduced-pressure TG-DTA Measurements were performed using TG-DTA at 10 Torr, Ar flow rate of 50 mL / min, heating rate of 10 °C / min, and a scanning temperature range of 30 °C to 600 °C. The temperature (°C) at which the test compound lost 50% by mass was evaluated as the "temperature (°C) at which the test compound lost 50% by mass under reduced pressure TG-DTA." A lower temperature (°C) at which the test compound lost 50% by mass under reduced pressure TG-DTA indicates that vapor can be obtained at a lower temperature. The results are shown in Table 1.

[0117] [ka]

[0118] [Table 1]

[0119] As shown in Table 1 above, Compounds No. 5, No. 8, No. 44 and No. 152 were liquid at 20° C. On the other hand, Comparative Compound 1 was solid at 20° C. and had a higher melting point than the compounds of the present invention.

[0120] [Evaluation example] The compounds of the present invention obtained in Examples 5 to 7 and the following comparative compound 2 were evaluated as follows. (1) Melting point evaluation The state of the compounds at 20° C. was observed visually. For those that were solid at 20° C., the melting points were measured using a micro melting point measuring device. The results are shown in Table 2. (2) Temperature (°C) at 50% mass loss in atmospheric pressure TG-DTA Measurements were performed using TG-DTA under atmospheric pressure with an Ar flow rate of 100 mL / min, a heating rate of 10°C / min, and a scanning temperature range of 30°C to 600°C. The temperature (°C) at which the weight of the test compound decreased by 50% by mass was evaluated as the "temperature (°C) at which the weight of the test compound decreased by 50% by mass using TG-DTA at atmospheric pressure." The results are shown in Table 2. (3) Temperature (°C) at 50% mass loss in reduced-pressure TG-DTA Measurements were performed using TG-DTA at 10 Torr, Ar flow rate of 50 mL / min, heating rate of 10 °C / min, and scanning temperature range of 30 °C to 600 °C. The temperature (°C) at which the test compound's weight was reduced by 50% was evaluated as the "temperature (°C) at which the test compound reduced by 50% by mass in reduced pressure TG-DTA." A lower temperature (°C) at which the test compound reduced by 50% by mass in reduced pressure TG-DTA indicates that vapor can be obtained at a lower temperature. The results are shown in Table 2.

[0121] [ka]

[0122] [Table 2]

[0123] As shown in Table 2 above, compounds No. 77 and No. 80 were liquid at 20° C. Compound No. 224 was solid at 20° C., but had a relatively low melting point of 43° C. On the other hand, comparative compound 2 was solid at 20° C. and had a melting point much higher than that of the compounds of the present invention.

[0124] [Examples 8 to 14 and Comparative Examples 1 to 3] Production of nitride films by ALD method Using the compounds of the present invention obtained in Examples 1 to 7, comparative compounds 1 and 2, and comparative compound 3 shown below as chemical vapor deposition raw materials, gallium nitride thin films or indium nitride thin films were produced on silicon substrates by ALD under the following conditions using the ALD apparatus shown in Figure 1. The film thickness of the obtained thin films was measured by X-ray reflectivity, the compounds in the thin films were identified by X-ray diffraction, and the carbon content in the thin films was measured by X-ray photoelectron spectroscopy. The results are shown in Table 3.

[0125] [ka]

[0126] (conditions) Reaction temperature (substrate temperature): 200°C, reactive gas: ammonia (Process) A series of steps (1) to (4) below constituted one cycle, and 150 cycles were repeated. (1) Vapor of the chemical vapor deposition source material vaporized under the conditions of a source container heating temperature of 90°C and a source container internal pressure of 100 Pa is introduced, and deposition is performed for 30 seconds at a system pressure of 100 Pa. (2) Unreacted raw materials are removed by purging with argon for 10 seconds. (3) A reactive gas is introduced and reacted at a system pressure of 100 Pa for 30 seconds. (4) Unreacted raw materials are removed by purging with argon for 10 seconds.

[0127] [Table 3]

[0128] The carbon content in the nitride films obtained by the ALD method was 5 atm% or more in Comparative Examples 1 to 3, but less than the detection limit of 0.1 atm% in Examples 8 to 14. This demonstrates that high-quality nitride films can be obtained by using the gallium compound and indium compound of the present invention. Furthermore, the thickness of the nitride films obtained was 3.5 nm or less in Comparative Examples 1 to 3, but 6.0 nm or more in Examples 8 to 14. This demonstrates that nitride films were obtained with high productivity by using the gallium compound and indium compound of the present invention. In particular, Compound No. 5 and Compound No. 8 were able to produce nitride films with high productivity when used as chemical vapor deposition sources, demonstrating their superiority as chemical vapor deposition sources.

[0129] [Examples 15 to 21 and Comparative Examples 4 to 6] Production of oxide films by ALD method Using the compounds of the present invention obtained in Examples 1 to 7 and comparative compounds 1 to 3 as chemical vapor deposition raw materials, gallium oxide thin films or indium oxide thin films were produced on silicon substrates by ALD under the following conditions using the ALD apparatus shown in Figure 1. The film thickness of the obtained thin films was measured by X-ray reflectivity, the compounds in the thin films were identified by X-ray diffraction, and the carbon content in the thin films was measured by X-ray photoelectron spectroscopy. The results are shown in Table 4.

[0130] (conditions) Reaction temperature (substrate temperature): 200°C, reactive gas: ozone (Process) A series of steps (1) to (4) below constituted one cycle, and 150 cycles were repeated. (1) Vapor of the chemical vapor deposition source material vaporized under the conditions of a source container heating temperature of 90°C and a source container internal pressure of 100 Pa is introduced, and deposition is performed for 30 seconds at a system pressure of 100 Pa. (2) Unreacted raw materials are removed by purging with argon for 10 seconds. (3) A reactive gas is introduced and reacted at a system pressure of 100 Pa for 30 seconds. (4) Unreacted raw materials are removed by purging with argon for 10 seconds.

[0131] [Table 4]

[0132] The carbon content in the oxide films obtained by the ALD method was 5 atm% or more in Comparative Examples 4 to 6, but less than the detection limit of 0.1 atm% in Examples 15 to 21. This indicates that high-quality oxide films can be obtained by using the gallium compound and indium compound of the present invention. Furthermore, the thickness of the obtained oxide films was 3.0 nm or less in Comparative Examples 4 to 6, but 5.5 nm or more in Examples 15 to 21. This indicates that oxide films were obtained with high productivity by using the gallium compound and indium compound of the present invention. In particular, Compounds No. 5 and No. 8 were able to produce oxide films with high productivity when used as chemical vapor deposition sources, demonstrating their superiority as chemical vapor deposition sources.

Claims

1. A compound represented by the following general formula (1) or (2): 【Chemical 1】 (In the formula, R １ and R ２ each independently represents an alkyl group having 1 to 3 carbon atoms or a group represented by the following general formula (X-1), and R ３ and R ４ each independently represents an alkyl group having 1 to 3 carbon atoms; R ５ and R ６ each independently represents a primary alkyl group having 1 to 5 carbon atoms; M １ represents a gallium atom or an indium atom. In the alkyl group having 1 to 3 carbon atoms and the primary alkyl group having 1 to 5 carbon atoms, some or all of the hydrogen atoms may be substituted with fluorine atoms. 【Chemistry 2】 (In the formula, R ２１ and R ２２ each independently represents an alkyl group having 1 to 5 carbon atoms, and * represents a bond. 【Chemistry 3】 (In the formula, R ７ and R ８ each independently represents an alkyl group having 1 to 3 carbon atoms; R ９ and R １０ each independently represents an alkyl group having 1 to 3 carbon atoms; R １１ represents a primary alkyl group having 1 to 5 carbon atoms, M ２ represents a gallium atom or an indium atom. In the alkyl group having 1 to 3 carbon atoms and the primary alkyl group having 1 to 5 carbon atoms, some or all of the hydrogen atoms may be substituted with fluorine atoms.

2. The compound represented by the general formula (2) is R ７ , R ８ , R ９ and R １０ is a methyl group, and R １１ The compound according to claim 1, wherein is a primary alkyl group having 1 to 5 carbon atoms.

3. A thin film-forming material containing the compound according to claim 1 or 2.

4. 4. A method for producing a thin film, comprising: introducing a source gas obtained by vaporizing the thin film-forming source material according to claim 3 into a processing atmosphere in which a substrate is placed; and decomposing and / or chemically reacting the compound in the source gas to form a thin film containing gallium atoms or indium atoms on the surface of the substrate.

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