JP2018076550A - Compound, Raw Material for Forming Thin Film, Raw Material for Forming Thin Film for Atomic Layer Deposition, and Thin Film Manufacturing Method - Google Patents

Abstract

Provided is a raw material for forming a thin film capable of producing a high-quality metal-containing thin film having a high vapor pressure, a low melting point, and an atomic layer volume method (ALD method). A thin film forming raw material containing a compound represented by the formula (1). (R1 to R6 are each independently H or C1-4 linear / branched alkyl group; R7 to R9 are C1-4 linear / branched alkyl group; M1 is zirconium, hafnium or titanium) Figure] None

Description

  The present invention relates to a novel compound, a raw material for forming a thin film containing the compound, and a method for producing a thin film using the raw material for forming a thin film. The present invention also relates to a novel thin film forming raw material for atomic layer deposition and a thin film manufacturing method using the thin film forming raw material.

  Thin films containing zirconium atoms, titanium atoms, or hafnium atoms are used for electronic components of electronic components such as high dielectric capacitors, ferroelectric capacitors, gate insulating films, barrier films, optical waveguides, optical switches, optical amplifiers, etc. It is used as an optical member for communication devices.

  Examples of the method for producing the thin film include a sputtering method, an ion plating method, a MOD method such as a coating pyrolysis method and a sol-gel method, a chemical vapor deposition method, etc., but has excellent composition controllability and step coverage. Since it has many advantages such as being suitable for mass production and being capable of hybrid integration, chemical vapor deposition (hereinafter sometimes referred to as CVD) or atomic layer deposition ( Hereinafter, it may be described as an ALD method) is an optimal manufacturing process.

  A large number of various raw materials have been reported as metal sources used in chemical vapor deposition. For example, Non-Patent Document 1 discloses tetrakis (1-dimethylamino-2-methyl-2-propoxy) zirconium and tetrakis (1-dimethylamino-2-methyl-2-) as materials for the ALD method of titanium and zirconium. Propoxy) titanium is disclosed. However, since the compound disclosed by Non-Patent Document 1 is a liquid having a very high viscosity, it has poor transportability and has a problem in productivity.

  Patent Document 1 discloses alkylcyclopentadienyl (dialkylamino) titanium as a raw material for the ALD method. However, when a film is formed using the compound disclosed in Patent Document 1, there is a problem that the residual carbon content in the film increases.

Special table 2010-539709 gazette

ECS Transactions (2009), 25 (4, Atomic layer Deposition Applications 5), 209-216

  When forming a thin film containing a metal on the surface of a substrate by vaporizing a raw material for chemical vapor deposition or the like, the raw material for forming a thin film can produce a high-quality metal-containing thin film having a high vapor pressure and a low melting point. Is required. None of the conventionally known materials for forming a thin film has such physical properties. Especially, in order to improve productivity, since it is necessary to improve the transportability of the raw material for forming a thin film, a material having a low melting point and a low viscosity has been strongly demanded. Moreover, since it is known that the thin film manufactured by the ALD method is higher in quality than the thin film manufactured by the MOCVD method, the metal-containing thin film can be manufactured by the ALD method, and the above problems can be solved. A raw material for forming a thin film has been desired.

  As a result of repeated studies, the present inventors have found that a specific compound can solve the above problems, and have reached the present invention. Further, the present inventors have found that a raw material for forming a thin film for an atomic layer deposition method containing a specific compound can solve the above problems, and have reached the present invention.

  The present invention provides a compound represented by the following general formula (1).

(Wherein R ^{1 to} R ⁶ each independently represent hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms, and R ⁷ , R ⁸ and R ⁹ are each a straight chain having 1 to 4 carbon atoms. Represents a chain or branched alkyl group, and M ¹ represents zirconium or titanium.)

  Moreover, this invention provides the raw material for thin film formation for atomic layer deposition methods formed by containing the compound represented by following General formula (2).

(In the formula, each of R ^{11 to} R ¹⁶ independently represents hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms, and R ¹⁷ , R ¹⁸ and R ¹⁹ are each a straight chain having 1 to 4 carbon atoms. Represents a chain or branched alkyl group, and M ² represents zirconium, hafnium or titanium.)

  According to the present invention, it is possible to obtain a compound having a high vapor pressure, a liquid having a normal pressure of 30 ° C. or slight heating, and a low viscosity. The compound is particularly suitable as a thin film forming raw material used for forming a metal-containing thin film by a method such as a CVD method or an ALD method. Further, according to the present invention, a thin film forming raw material for an atomic layer deposition method capable of forming a high-quality metal-containing thin film can be obtained.

FIG. 1 is a schematic view showing an example of an apparatus for chemical vapor deposition used in the method for producing a thin film according to the present invention. FIG. 2 is a schematic diagram showing another example of a chemical vapor deposition apparatus used in the thin film manufacturing method according to the present invention. FIG. 3 is a schematic view showing another example of the chemical vapor deposition apparatus used in the method for producing a thin film according to the present invention. FIG. 4 is a schematic diagram showing another example of a chemical vapor deposition apparatus used in the thin film manufacturing method according to the present invention.

  The compound of the present invention is represented by the above general formula (1), is suitable as a precursor for a thin film production method having a vaporization step such as a CVD method, and forms a thin film using an ALD method. You can also. The compound of the present invention is a compound which is liquid at normal pressure of 30 ° C. or becomes liquid by slight heating and has a low viscosity. A compound having a low melting point and a low viscosity has good transportability, and thus is suitable as a precursor for a thin film production method having a vaporization step such as a CVD method.

In the general formula (1), examples of the linear or branched alkyl group having 1 to 4 carbon atoms represented by R ^{1 to} R ⁹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, and butyl. Group, isobutyl group, secondary butyl group, tertiary butyl group and the like.

From the viewpoint that the melting point of the compound is low, in the general formula (1), R ^{1 to} R ⁵ are preferably hydrogen or a methyl group, and all of R ^{1 to} R ⁵ are hydrogen or R ^{1 to} R 5 compound one is and the remaining four are hydrogen or a methyl group of ⁵ are particularly preferred. From the viewpoint that the melting point of the compound is low and the vapor pressure is high, in the above general formula (1), R ⁶ is preferably a hydrogen, a primary alkyl group or a secondary alkyl group, preferably a methyl group, an ethyl group, A compound which is a propyl group or an isopropyl group is more preferable, and a compound which is a methyl group, an ethyl group or a propyl group is particularly preferable. From the viewpoint that the melting point of the compound is low and the vapor pressure is high, in the general formula (1), R ⁷ is preferably a primary alkyl group or a secondary alkyl group, and is preferably a methyl group, an ethyl group or a propyl group. Or the compound which is an isopropyl group is more preferable, and the compound which is a methyl group, an ethyl group, or a propyl group is especially preferable. In the general formula (1), a compound in which R ⁶ and R ⁷ are a methyl group or an ethyl group is preferable because it has a low melting point and a high vapor pressure. In the general formula (1), R ⁸ and R ⁹ are preferably a primary alkyl group, more preferably a methyl, ethyl or propyl group, particularly a methyl or ethyl group. preferable. In the case of a method for producing a thin film by the MOD method that does not involve a vaporization step, R ^{1 to} R ⁹ can be appropriately selected depending on the solubility in the solvent used, the thin film formation reaction, and the like.

Preferable specific examples of the compound in which M ¹ is zirconium in the general formula (1) include, for example, the following compound No. 1-No. 18 is mentioned. In addition, the following compound No. 1-No. In “18”, “Me” represents a methyl group, and “Et” represents an ethyl group.

In the general formula (1), preferred specific examples of the compound in which M ¹ is titanium include, for example, the following compound No. 19-No. 36. In addition, the following compound No. 19-No. In 36, “Me” represents a methyl group, and “Et” represents an ethyl group.

The compound of the present invention is not particularly limited by its production method, and is produced by applying a known reaction. Of the compounds represented by the general formula (1), when producing a compound in which M ¹ is zirconium, for example, tetrakis (dialkylamino) zirconium is used as a starting material, and cyclopentadiene or alkylcyclopentadiene is added here. After the reaction, it can be produced by reacting a corresponding dialkylamino alcohol. In the case of producing a compound in which M ¹ is titanium, it can be produced by a method similar to the above production method except that tetrakis (alkylamino) titanium or the like is used as a starting material.

  The thin film forming raw material of the present invention is a thin film precursor obtained by using the compound of the present invention described above, and the form thereof varies depending on the production process to which the thin film forming raw material is applied. For example, when producing a thin film containing only zirconium atoms or titanium atoms, the raw material for forming a thin film of the present invention does not contain a metal compound other than the above compounds. On the other hand, in the case of producing a thin film containing two or more kinds of metals and / or metalloids, the raw material for forming a thin film of the present invention includes a compound containing a desired metal and / or a compound containing a metalloid in addition to the above compound ( (Hereinafter also referred to as other precursor). As will be described later, the thin film forming raw material of the present invention may further contain an organic solvent and / or a nucleophilic reagent. As described above, the thin film forming raw material of the present invention is suitable for the chemical vapor deposition material (hereinafter sometimes referred to as a CVD raw material) because the physical properties of the precursor compound are suitable for the CVD method and the ALD method. Useful as.

  In the case where the thin film forming raw material of the present invention is a chemical vapor deposition raw material, the form is appropriately selected depending on the method such as the transporting and supplying method of the CVD method used.

  As the above transportation and supply method, the raw material for CVD is vaporized by heating and / or depressurizing in a container in which the raw material is stored (hereinafter sometimes simply referred to as a raw material container), and is necessary. Gas transport method for introducing a vapor into a film forming chamber (hereinafter also referred to as a deposition reaction part) where a substrate is installed, together with a carrier gas such as argon, nitrogen, helium or the like used accordingly, for CVD There is a liquid transport method in which a raw material is transported to a vaporization chamber in a liquid or solution state, vaporized by being heated and / or decompressed in the vaporization chamber to be vaporized, and the vapor is introduced into a film formation chamber. In the case of the gas transport method, the compound itself represented by the general formula (1) can be used as a raw material for CVD. In the case of the liquid transport method, the compound itself represented by the general formula (1) or a solution obtained by dissolving the compound in an organic solvent can be used as a CVD raw material. These CVD raw materials may further contain other precursors, nucleophilic reagents, and the like.

  In the multi-component CVD method, the CVD raw material is vaporized and supplied independently for each component (hereinafter sometimes referred to as a single source method), and the multi-component raw material is mixed in advance with a desired composition. There is a method of vaporizing and supplying a mixed raw material (hereinafter, sometimes referred to as a cocktail sauce method). In the case of the cocktail sauce method, a mixture of the compound of the present invention and another precursor or a mixed solution obtained by dissolving the mixture in an organic solvent can be used as a raw material for CVD. This mixture or mixed solution may further contain a nucleophilic reagent and the like.

  As said organic solvent, it does not receive a restriction | limiting in particular, A well-known common 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 butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, methylcyclohexanone; hexane, cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, toluene, Hydrocarbons such as xylene; 1-cyanopropane, 1-cyanobutane, 1-cyanohexa , Hydrocarbons having a cyano group such as cyanocyclohexane, cyanobenzene, 1,3-dicyanopropane, 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, 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 use temperature and boiling point, the flash point, and the like. When these organic solvents are used, the total amount of the precursor in the CVD raw material, which is a solution obtained by dissolving the precursor in the organic solvent, is 0.01 to 2.0 mol / liter, particularly 0.05 to 1.0 mol / liter. It is preferable to make it liter. The amount of the entire precursor is the amount of the compound of the present invention when the thin film forming raw material of the present invention does not contain a metal compound and a semimetal compound other than the compound of the present invention. When the raw material contains a compound containing another metal and / or a compound containing a metalloid (another precursor) in addition to the compound, it is the total amount of the compound of the present invention and the other precursor.

  In the case of a multi-component CVD method, the other precursor used together with the compound of the present invention is not particularly limited, and a known general precursor used for a CVD raw material can be used.

  Other precursors mentioned above include hydrides, hydroxides, halides, azides, alkyls, alkenyls, cycloalkyls, aryls, alkynyls, aminos, dialkylaminoalkyls, monoalkylaminos, dialkylaminos, diamines, di (silyls) -Alkyl) amino, di (alkyl-silyl) amino, disilylamino, alkoxy, alkoxyalkyl, hydrazide, phosphide, nitrile, dialkylaminoalkoxy, alkoxyalkyldialkylamino, siloxy, diketonate, cyclopentadienyl, silyl, pyrazolate, guanidinate, One type selected from the group consisting of phosphoguanidinate, amidinate, ketoiminate, diketiminate, carbonyl and phosphoamidinate as a ligand Compounds of kinds of silicon or metal.

  The precursor metal species include magnesium, calcium, strontium, barium, radium, scandium, zirconium, titanium, hafnium, yttrium, vanadium, niobium, tantalum, manganese, iron, chromium, molybdenum, tungsten, osmium, ruthenium, cobalt, rhodium. , Iridium, nickel, palladium, platinum, copper, silver, gold, zinc, aluminum, gallium, indium, germanium, tin, lead, antimony, bismuth, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium , Terbium, dysprosium, holmium, erbium, thulium, ytterbium.

  Other precursors described above are known in the art, and their production methods are also known. As an example of the production method, for example, when an alcohol compound is used as the organic ligand, the inorganic salt of metal or its hydrate described above is reacted with the alkali metal alkoxide of the alcohol compound. Thus, a precursor can be manufactured. Here, examples of the metal inorganic salt or hydrate include metal halides and nitrates, and examples of the alkali metal alkoxide include sodium alkoxide, lithium alkoxide, and potassium alkoxide.

  In the case of the single source method, the above-mentioned other precursor is preferably a compound having similar thermal and / or oxidative degradation behavior to the compound of the present invention, and in the case of the cocktail source method, thermal and / or oxidative degradation. In addition to the similar behaviors, those that do not cause alteration due to chemical reaction or the like during mixing are preferred.

  In addition, the raw material for forming a thin film of the present invention may contain a nucleophilic reagent as needed to impart stability of the compound of the present invention and other precursors. Examples of the nucleophilic reagent include ethylene glycol ethers such as glyme, diglyme, triglyme and tetraglyme, 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8. , Crown ethers such as dibenzo-24-crown-8, ethylenediamine, N, N, N′N′-tetramethylethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4, 7,7-pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine, polyamines such as triethoxytriethyleneamine, cyclic polyamines such as cyclam and cyclen, pyridine, pyrrolidi , Piperidine, morpholine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, oxazole, thiazole, oxathiolane and other heterocyclic compounds, methyl acetoacetate, ethyl acetoacetate Β-ketoesters such as acetoacetate-2-methoxyethyl or β-diketones such as acetylacetone, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, and dipivaloylmethane. Can be mentioned. The amount of these nucleophilic reagents used is preferably in the range of 0.1 mol to 10 mol, more preferably in the range of 1 to 4 mol, relative to 1 mol of the entire precursor.

  The raw material for forming a thin film according to the present invention contains as little impurities metal elements as possible, impurities halogen such as impurity chlorine, and impurities organic components as much as possible. The impurity metal element content is preferably 100 ppb or less for each element, more preferably 10 ppb or less, and the total amount is preferably 1 ppm or less, more preferably 100 ppb or less. In particular, when used as an LSI gate insulating film, gate film, or barrier layer, it is necessary to reduce the content of alkali metal elements and alkaline earth metal elements that affect the electrical characteristics of the thin film obtained. The impurity halogen content is preferably 100 ppm or less, more preferably 10 ppm or less, and most preferably 1 ppm or less. The impurity organic content is preferably 500 ppm or less in total, more preferably 50 ppm or less, and most preferably 10 ppm or less. In addition, since moisture causes generation of particles in the raw material for chemical vapor deposition and generation of particles during thin film formation, the precursor, organic solvent, and nucleophilic reagent are used to reduce their respective moisture. It is better to remove moisture as much as possible before use. The moisture content of each of the precursor, the organic solvent, and the nucleophilic reagent is preferably 10 ppm or less, and more preferably 1 ppm or less.

  Moreover, it is preferable that the raw material for forming a thin film of the present invention contains particles as little as possible in order to reduce or prevent particle contamination of the formed thin film. Specifically, in the particle measurement by the light scattering liquid particle detector in the liquid phase, the number of particles larger than 0.3 μm is preferably 100 or less in 1 mL of the liquid phase, and larger than 0.2 μm. The number of particles is more preferably 1000 or less in 1 mL of the liquid phase, and the number of particles larger than 0.2 μm is most preferably 100 or less in 1 mL of the liquid phase.

  As a method for producing a thin film of the present invention for producing a thin film using the thin film forming raw material of the present invention, a vapor obtained by vaporizing the thin film forming raw material of the present invention and a reactive gas used as necessary are used as a substrate. The film is introduced into a film forming chamber in which is deposited, and then a precursor is decomposed and / or chemically reacted on the substrate to grow and deposit a metal-containing thin film on the surface of the substrate. There are no particular restrictions on the method of transporting and supplying the raw material, the deposition method, the production conditions, the production apparatus, etc., and well-known general conditions and methods can be used.

  Examples of the reactive gas used as necessary include oxygen, ozone, nitrogen dioxide, nitric oxide, water vapor, hydrogen peroxide, formic acid, acetic acid, acetic anhydride, etc. Examples of reducing substances include hydrogen, and examples of nitrides that can be used include organic amine compounds such as monoalkylamines, dialkylamines, trialkylamines, and alkylenediamines, hydrazine, and ammonia. Can be used alone or in combination of two or more. Among these, since the raw material for forming a thin film of the present invention has good reactivity with ozone, it is preferable to use ozone when one kind is used as the reactive gas, and two or more kinds as the reactive gas. When using a mixed gas, it is preferable to contain at least ozone.

  Examples of the transport and supply method include the gas transport method, liquid transport method, single source method, and cocktail sauce method described above.

  In addition, the above deposition methods include thermal CVD in which a raw material gas or a raw material gas and a reactive gas are reacted only by heat to deposit a thin film, plasma CVD using heat and plasma, photo CVD using heat and light, In addition, optical plasma CVD using light and plasma, and ALD in which the deposition reaction of CVD is divided into elementary processes and deposition is performed stepwise at the molecular level.

  Examples of the material of the base 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; metals such as metal ruthenium. It is done. Examples of the shape of the substrate include a plate shape, a spherical shape, a fiber shape, and a scale shape. The substrate surface may be a flat surface or a three-dimensional structure such as a trench structure.

Moreover, as said manufacturing conditions, reaction temperature (base | substrate temperature), reaction pressure, a deposition rate, etc. are mentioned. About reaction temperature, 100 degreeC or more which is the temperature which the compound of this invention fully reacts is preferable, 150 to 400 degreeC is more preferable, 200 to 350 degreeC is especially preferable. The reaction pressure is preferably atmospheric pressure to 10 Pa in the case of thermal CVD or photo CVD, and preferably 2000 Pa to 10 Pa in the case of using plasma.
The deposition rate can be controlled by the raw material supply conditions (vaporization temperature, vaporization pressure), reaction temperature, and reaction pressure. When the deposition rate is large, the properties of the obtained thin film may be deteriorated. When the deposition rate is small, a problem may be caused in productivity. Therefore, 0.01 to 100 nm / min is preferable, and 1 to 50 nm / min is more preferable. In the case of the ALD method, the number of cycles is controlled so as to obtain a desired film thickness.

  The production conditions further include temperature and pressure when the thin film forming raw material is vaporized into steam. The step of vaporizing the raw material for forming a thin film to form a vapor may be performed in a raw material container or in a vaporization chamber. In any case, the thin film forming raw material of the present invention is preferably evaporated at 0 to 150 ° C. In addition, when the thin film forming raw material is vaporized in the raw material container or in the vaporization chamber to form a vapor, the pressure in the raw material container and the pressure in the vaporization chamber are both preferably 1 to 10,000 Pa.

  The thin film production method of the present invention employs the ALD method, and in addition to the raw material introduction step of vaporizing the thin film forming raw material into vapor by the above transport and supply method, and introducing the vapor into the film forming chamber, A precursor thin film forming step of forming a precursor thin film on the surface of the substrate by the compound in the vapor, an exhausting step of exhausting unreacted compound gas, and chemically reacting the precursor thin film with a reactive gas; You may have the metal containing thin film formation process which forms the thin film containing a metal on the surface of this base | substrate.

  Below, the case where a metal oxide thin film is formed is demonstrated in detail about each said process as an example. When the metal oxide thin film is formed by the ALD method, first, the raw material introduction step described above is performed. Preferred temperatures and pressures when the thin film forming raw material is steam are the same as those described above. Next, a precursor thin film is formed on the surface of the substrate by the compound introduced into the deposition reaction part (precursor thin film forming step). At this time, heat may be applied by heating the substrate or heating the deposition reaction part. The precursor thin film formed in this step is a thin film formed from the compound of the present invention, or a thin film formed by decomposition and / or reaction of a part of the compound of the present invention. It has a composition different from the physical thin film. The substrate temperature when this step is performed is preferably room temperature to 500 ° C, more preferably 150 to 350 ° C. The pressure of the system (in the film forming chamber) when this step is performed is preferably 1 to 10,000 Pa, and more preferably 10 to 1000 Pa.

  Next, unreacted compound gas and by-product gas are exhausted from the deposition reaction part (exhaust process). Ideally, unreacted compound gas and by-produced gas are completely exhausted from the deposition reaction part, but it is not always necessary to exhaust completely. Examples of the exhaust method include a method of purging the system with an inert gas such as nitrogen, helium, and argon, a method of exhausting by reducing the pressure in the system, and a method combining these. When the pressure is reduced, the degree of pressure reduction is preferably 0.01 to 300 Pa, and more preferably 0.01 to 100 Pa.

  Next, an oxidizing gas is introduced into the deposition reaction part, and a metal oxide thin film is formed from the precursor thin film obtained in the precursor thin film forming step by the action of the oxidizing gas or the action of the oxidizing gas and heat. Form (metal oxide-containing thin film forming step). The temperature when heat is applied in this step is preferably room temperature to 500 ° C, more preferably 150 to 350 ° C. The pressure of the system (in the film forming chamber) when this step is performed is preferably 1 to 10,000 Pa, and more preferably 10 to 1000 Pa. Since the compound of the present invention has good reactivity with an oxidizing gas, a high-quality metal oxide thin film with a low residual carbon content can be obtained.

  In the thin film manufacturing method of the present invention, when the ALD method is employed as described above, the thin film is formed by a series of operations including the raw material introduction step, precursor thin film formation step, exhaust step, and metal oxide-containing thin film formation step. The deposition may be one cycle, and this cycle may be repeated a plurality of times until a thin film having a required film thickness is obtained. In this case, after one cycle, the unreacted compound gas and reactive gas (oxidizing gas in the case of forming a metal oxide thin film) and further by-produced gas from the deposition reaction part in the same manner as the exhaust process. After exhausting, it is preferable to perform the next one cycle.

  In forming the metal oxide 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 the timing of using the catalyst are not particularly limited. For example, when introducing a compound gas in the raw material introducing step, heating in the precursor thin film forming step or metal oxide-containing thin film forming step, exhausting It may be at the time of exhausting the system in the process, at the time of introducing the oxidizing gas in the metal oxide-containing thin film forming process, or between the above-mentioned processes.

  In the method for producing a thin film of the present invention, after thin film deposition, annealing may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere in order to obtain better electrical characteristics. When embedding is necessary, a reflow process may be provided. The temperature in this case is 200 to 1000 ° C, preferably 250 to 500 ° C.

  As a device for producing a thin film using the raw material for forming a thin film of the present invention, a well-known chemical vapor deposition apparatus can be used. Specific examples of the apparatus include an apparatus capable of supplying a precursor as shown in FIG. 1 and an apparatus having a vaporization chamber as shown in FIG. In addition, as shown in FIGS. 3 and 4, an apparatus capable of performing plasma treatment on a reactive gas can be used. The present invention is not limited to the single wafer type apparatus as shown in FIGS.

  A thin film containing a metal produced using the raw material for forming a thin film of the present invention is used for a cutting tool, a wiring or an electrode for an electronic material, for example, an electrode for a semiconductor memory material or a lithium air battery. Can be used.

  The thin film forming raw material for the atomic layer deposition method of the present invention contains a compound represented by the following general formula (2).

(In the formula, each of R ^{11 to} R ¹⁶ independently represents hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms, and R ¹⁷ , R ^18, and R ¹⁹ are each a straight chain having 1 to 4 carbon atoms. Represents a chain or branched alkyl group, and M ² represents zirconium, hafnium or titanium.)

In the general formula (2), examples of the linear or branched alkyl group having 1 to 4 carbon atoms represented by R ^{11 to} R ¹⁹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, and butyl. Group, isobutyl group, secondary butyl group, tertiary butyl group and the like.

From the standpoint of low melting point compounds, in the general formula ^(2), R 11 ^{to R 15} is preferably represent hydrogen or ^methyl, or ^R 11 or all of them are hydrogen R 11 ^{to R 15} to R Particularly preferred are compounds in which one of ¹⁵ is a methyl group and the remaining four are hydrogen. From the viewpoint that the melting point of the compound is low and the vapor pressure is high, in the general formula (2), R ¹⁶ is preferably a hydrogen, a primary alkyl group or a secondary alkyl group, preferably a methyl group, an ethyl group, A compound which is a propyl group or an isopropyl group is more preferable, and a compound which is a methyl group, an ethyl group or a propyl group is particularly preferable. In view of the low melting point and high vapor pressure of the compound, in the above general formula (2), R ¹⁷ is preferably a primary alkyl group or a secondary alkyl group, and is preferably a methyl group, an ethyl group or a propyl group. Or the compound which is an isopropyl group is more preferable, and the compound which is a methyl group, an ethyl group, or a propyl group is especially preferable. In the general formula (2), a compound in which R ¹⁶ and R ¹⁷ are a methyl group or an ethyl group is preferable because it has a low melting point and a high vapor pressure. In the general formula (2), R ¹⁸ and R ¹⁹ are preferably a primary alkyl group, more preferably a methyl, ethyl or propyl group, and particularly a methyl or ethyl group. preferable.

Preferable specific examples of the compound represented by the general formula (2) include the compound No. 1 described above. 1 to 36, and in the above general formula (2), as a compound in which M ² is hafnium, the following compound No. 1 is used. 37-No. 54. In addition, the following compound No. 37-No. In “54”, “Me” represents a methyl group, and “Et” represents an ethyl group.

The compound used for the raw material for forming a thin film for the atomic layer deposition method of the present invention is not particularly limited by the production method, and is produced by applying a known reaction. Among the compounds represented by the general formula (2), when producing a compound in which M ² is zirconium or titanium, it can be produced by the above-described method, and a compound in which M ² is hafnium is produced. In this case, it can be produced by the same method as the above production method except that tetrakis (alkylamino) hafnium is used as a starting material.

  The form of the thin film forming raw material for the atomic layer deposition method of the present invention (hereinafter sometimes referred to as ALD raw material) is appropriately selected depending on the method of transporting and supplying the ALD method used.

  As the above transportation and supply method, the ALD raw material is vaporized by heating and / or depressurizing in a container in which the raw material is stored (hereinafter sometimes simply referred to as a raw material container), and is necessary. Along with a carrier gas such as argon, nitrogen, and helium used accordingly, a gas transport method for introducing the vapor into the deposition reaction section where the substrate is installed, transporting the ALD raw material in a liquid or solution state to the vaporization chamber, There is a liquid transport method in which vaporization is performed by heating and / or decompressing in a vaporization chamber to form vapor, and the vapor is introduced into a film formation chamber. In the case of the gas transport method, the compound itself represented by the general formula (2) can be used as a raw material for ALD. In the case of the liquid transport method, the compound itself represented by the general formula (2) or a solution obtained by dissolving the compound in an organic solvent can be used as a raw material for ALD. These raw materials for ALD may further contain a nucleophilic reagent and the like.

  As said organic solvent, it does not receive a restriction | limiting in particular, A well-known common 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 butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, methylcyclohexanone; hexane, cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, toluene, Hydrocarbons such as xylene; 1-cyanopropane, 1-cyanobutane, 1-cyanohexa , Hydrocarbons having a cyano group such as cyanocyclohexane, cyanobenzene, 1,3-dicyanopropane, 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, 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 use temperature and boiling point, the flash point, and the like. When these organic solvents are used, the amount of the compound represented by the general formula (2) in the raw material for ALD, which is a solution obtained by dissolving the compound represented by the general formula (2) in the organic solvent, is 0.00. It is preferable that the amount be 01 to 2.0 mol / liter, particularly 0.05 to 1.0 mol / liter.

  Moreover, the raw material for forming a thin film for the atomic layer deposition method may contain a nucleophilic reagent as needed to impart stability of the compound of the present invention. Examples of the nucleophilic reagent include ethylene glycol ethers such as glyme, diglyme, triglyme and tetraglyme, 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8. , Crown ethers such as dibenzo-24-crown-8, ethylenediamine, N, N′-tetramethylethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4,7,7- Polyamines such as pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine and triethoxytriethyleneamine, cyclic polyamines such as cyclam and cyclen, pyridine, pyrrolidine and pipette Heterocyclic compounds such as gin, morpholine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, oxazole, thiazole, oxathiolane, methyl acetoacetate, ethyl acetoacetate, Β-ketoesters such as acetoacetate-2-methoxyethyl or β-diketones such as acetylacetone, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, and dipivaloylmethane It is done. The amount of these nucleophilic reagents used is preferably in the range of 0.1 mol to 10 mol, more preferably in the range of 1 to 4 mol, relative to 1 mol of the compound represented by the general formula (2). .

  The raw material for forming a thin film for the atomic layer deposition method of the present invention is made to contain as little impurities metal elements as possible, impurities halogen such as impurity chlorine, and impurities organic components as much as possible. The impurity metal element content is preferably 100 ppb or less for each element, more preferably 10 ppb or less, and the total amount is preferably 1 ppm or less, more preferably 100 ppb or less. In particular, when used as an LSI gate insulating film, gate film, or barrier layer, it is necessary to reduce the content of alkali metal elements and alkaline earth metal elements that affect the electrical characteristics of the thin film obtained. The impurity halogen content is preferably 100 ppm or less, more preferably 10 ppm or less, and most preferably 1 ppm or less. The impurity organic content is preferably 500 ppm or less in total, more preferably 50 ppm or less, and most preferably 10 ppm or less. Further, since moisture causes generation of particles in the raw material for chemical vapor deposition and generation of particles during thin film formation, the compound represented by the general formula (2), the organic solvent, and the nucleophilic reagent In order to reduce the water content, it is better to remove water as much as possible before use. The water content of each of the compound represented by the general formula (2), the organic solvent, and the nucleophilic reagent is preferably 10 ppm or less, and more preferably 1 ppm or less.

  Moreover, it is preferable that the raw material for forming a thin film for the atomic layer deposition method of the present invention contains as little particles as possible in order to reduce or prevent particle contamination of the formed thin film. Specifically, in the particle measurement by the light scattering liquid particle detector in the liquid phase, the number of particles larger than 0.3 μm is preferably 100 or less in 1 mL of the liquid phase, and larger than 0.2 μm. The number of particles is more preferably 1000 or less in 1 mL of the liquid phase, and the number of particles larger than 0.2 μm is most preferably 100 or less in 1 mL of the liquid phase.

  The thin film production method of the present invention for producing a thin film by the ALD method using the thin film forming raw material for the atomic layer deposition method of the present invention is not particularly limited, and the well-known general conditions and methods described above are used. Can be used.

  Examples of the reactive gas used in the production of a thin film by the ALD method include oxygen, ozone, nitrogen dioxide, nitric oxide, water vapor, hydrogen peroxide, formic acid, acetic acid, acetic anhydride and the like as oxidizing gases. In addition, hydrogen is exemplified as a reducing substance, and examples of those that produce nitride include organic amine compounds such as monoalkylamine, dialkylamine, trialkylamine, and alkylenediamine, hydrazine, ammonia, and the like. These can be used alone or in combination of two or more. Among these, since the raw material for forming a thin film for the atomic deposition method of the present invention has good reactivity with ozone, it is preferable to use ozone when one kind is used as the reactive gas. When two or more kinds of mixed gases are used, it is preferable that at least ozone be included.

  Examples of the transport and supply method during the production of the thin film by the ALD method include the gas transport method, the liquid transport method, the single source method, and the cocktail source method described above.

  Examples of the material of the substrate used for manufacturing the thin film by the ALD method 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 A metal such as ruthenium metal. Examples of the shape of the substrate include a plate shape, a spherical shape, a fiber shape, and a scale shape. The substrate surface may be a flat surface or a three-dimensional structure such as a trench structure.

  Moreover, as said manufacturing conditions, reaction temperature (base | substrate temperature), a deposition rate, etc. are mentioned. About reaction temperature, 100 degreeC or more which is the temperature which the compound represented by the said General formula (2) fully reacts is preferable, 150 to 400 degreeC is more preferable, 150 to 350 degreeC is especially preferable. The deposition rate can be controlled by the raw material supply conditions (vaporization temperature, vaporization pressure), reaction temperature, and reaction pressure. If the deposition rate is large, the properties of the obtained thin film may be deteriorated. If the deposition rate is small, productivity may be problematic. Therefore, 0.01 to 0.1 nm / cycle is preferable.

  The production conditions further include temperature and pressure when vaporizing the raw material for forming a thin film for the atomic layer deposition method into vapor. The step of vaporizing the raw material for forming a thin film for the atomic layer deposition method into a vapor may be performed in a raw material container or in a vaporization chamber. In any case, the thin film forming raw material for the atomic layer deposition method of the present invention is preferably evaporated at 0 to 150 ° C. Moreover, when vaporizing the raw material for forming a thin film for the atomic layer deposition method in the raw material container or in the vaporization chamber to form a vapor, the pressure in the raw material container and the pressure in the vaporization chamber are preferably 1 to 10,000 Pa.

  The thin film manufacturing method of the present invention adopts the ALD method, vaporizes the thin film forming raw material for the atomic layer deposition method into vapor by the above-described transport supply method, and introduces the vapor into the film forming chamber. In addition to the raw material introduction step, a precursor thin film forming step for forming a precursor thin film on the surface of the substrate with the compound represented by the general formula (2) in the vapor, and an exhaust step for exhausting unreacted compound gas The precursor thin film may be chemically reacted with a reactive gas to form a metal-containing thin film forming step for forming a metal-containing thin film on the surface of the substrate.

  Below, the case where a metal oxide thin film is formed is demonstrated in detail about each said process as an example. When the metal oxide thin film is formed by the ALD method, first, the raw material introduction step described above is performed. The preferable temperature and pressure when the raw material for forming a thin film for atomic layer deposition is vapor are the same as those described above. Next, a precursor thin film is formed on the surface of the substrate by the compound introduced into the deposition reaction part (precursor thin film forming step). At this time, heat may be applied by heating the substrate or heating the deposition reaction part. The precursor thin film formed in this step is a thin film formed from the compound represented by the general formula (2), or a part of the compound represented by the general formula (2) is decomposed and / or Or it is the thin film produced | generated by reaction, and has a composition different from the target metal oxide thin film. The substrate temperature when this step is performed is preferably from 100 to 400 ° C, more preferably from 150 to 350 ° C. The pressure of the system (in the film forming chamber) when this step is performed is preferably 1 to 10,000 Pa, and more preferably 10 to 1000 Pa.

  Next, unreacted compound gas and by-product gas are exhausted from the deposition reaction part (exhaust process). Ideally, unreacted compound gas and by-produced gas are completely exhausted from the deposition reaction part, but it is not always necessary to exhaust completely. Examples of the exhaust method include a method of purging the system with an inert gas such as nitrogen, helium, and argon, a method of exhausting by reducing the pressure in the system, and a method combining these. When the pressure is reduced, the degree of pressure reduction is preferably 0.01 to 300 Pa, and more preferably 0.01 to 100 Pa.

  Next, an oxidizing gas is introduced into the deposition reaction part, and a metal oxide thin film is formed from the precursor thin film obtained in the precursor thin film forming step by the action of the oxidizing gas or the action of the oxidizing gas and heat. Form (metal oxide-containing thin film forming step). The temperature when heat is applied in this step is preferably room temperature to 500 ° C, more preferably 150 to 350 ° C. The pressure of the system (in the film forming chamber) when this step is performed is preferably 1 to 10,000 Pa, and more preferably 10 to 1000 Pa. Since the compound represented by the general formula (2) has good reactivity with an oxidizing gas, a metal oxide thin film having a small residual carbon content can be obtained.

  In the thin film manufacturing method of the present invention, when the ALD method is employed as described above, the thin film is formed by a series of operations including the raw material introduction step, precursor thin film formation step, exhaust step, and metal oxide-containing thin film formation step. The deposition may be one cycle, and this cycle may be repeated a plurality of times until a thin film having a required film thickness is obtained. In this case, after one cycle, the unreacted compound gas and reactive gas (oxidizing gas in the case of forming a metal oxide thin film) and further by-produced gas from the deposition reaction part in the same manner as the exhaust process. After exhausting, it is preferable to perform the next one cycle.

  In forming the metal oxide 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 the timing of using the catalyst are not particularly limited. For example, when introducing a compound gas in the raw material introducing step, heating in the precursor thin film forming step or metal oxide-containing thin film forming step, exhausting It may be at the time of exhausting the system in the process, at the time of introducing the oxidizing gas in the metal oxide-containing thin film forming process, or between the above-mentioned processes.

  In the method for producing a thin film of the present invention, after thin film deposition, annealing may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere in order to obtain better electrical characteristics. When embedding is necessary, a reflow process may be provided. The temperature in this case is 200 to 1000 ° C, preferably 250 to 500 ° C.

  As a device for producing a thin film using the thin film forming raw material for the atomic layer deposition method of the present invention, a known chemical vapor deposition method device can be used. Specific examples of the apparatus include an apparatus capable of supplying a precursor as shown in FIG. 1 and an apparatus having a vaporization chamber as shown in FIG. In addition, as shown in FIGS. 3 and 4, an apparatus capable of performing plasma treatment on a reactive gas can be used. The present invention is not limited to the single wafer type apparatus as shown in FIGS.

  The metal-containing thin film produced by using the thin film forming raw material for the atomic layer deposition method of the present invention is used in wiring and electrodes for cutting tools and electronic materials, such as semiconductor memory materials and lithium air. It can be used for a battery electrode or the like.

  Hereinafter, the present invention will be described in more detail with examples and evaluation examples. However, the present invention is not limited by the following examples.

Example 1 Compound No. 1 4. Preparation of No. 4 A mixed solution of 230.0 g of tetrakis (dimethylamino) zirconium and 1190 g of dehydrated toluene was placed in an ice bath in a 2000 mL four-necked flask under an Ar atmosphere, and then 113.7 g of cyclopentadiene was added from an equal pressure dropping funnel over about 1 hour. The reaction was conducted dropwise. Subsequently, 201.5 g of 1- (dimethylamino) -2-methyl-2-propanol was added dropwise from an isobaric dropping funnel over about 2 hours and reacted. After completion of the dropwise addition, the temperature was gradually raised to room temperature, and the reaction was further continued for 2 hours. Subsequently, after distilling off the solvent under reduced pressure, a fraction obtained by distillation under reduced pressure at 67 Pa / 145 to 7 ° C. was collected to obtain compound No. 1 as a pale yellow liquid. 312 g of 4 was obtained.

(Analysis value)
(1) Normal pressure TG-DTA
Mass 50% decrease temperature: 271 ° C. (Ar flow rate: 100 mL / min, temperature increase: 10 ° C./min, sample amount: 11.491 mg)
(2) Elemental analysis (metal analysis: ICP-AES, CHN analysis: CHN analyzer)
Zirconium content: 20.05 mass% (theoretical value: 20.10 mass%)
C: 58.0 mass% (theoretical value: 58.23 mass%), H: 7.9 mass% (theoretical value: 8.44 mass%), N: 5.8 mass% (theoretical value: 6.17) mass%)

Example 2 Compound No. Preparation of No. 22 A mixed solution of 19.3 g of tetrakis (dimethylamino) titanium and 118.9 g of dehydrated toluene was placed in an ice bath in a 300 mL four-necked flask under an Ar atmosphere, and then 12.0 g of cyclopentadiene was added from an isobaric dropping funnel for about 30 hours. Over a period of time to cause reaction. Subsequently, 20.2 g of 1- (dimethylamino) -2-methyl-2-propanol was dropped from the isobaric dropping funnel over about 1 hour and reacted. After completion of the dropwise addition, the temperature was gradually raised to room temperature, and the reaction was further continued for 2 hours. Subsequently, after distilling off the solvent under reduced pressure, distillation under reduced pressure was performed to obtain a pale yellow liquid compound No. 28.2g of 22 was obtained.

(Analysis value)
(1) Normal pressure TG-DTA
Mass 50% decrease temperature: 272 ° C. (Ar flow rate: 100 mL / min, temperature increase: 10 ° C./min, sample amount: 10.421 mg)
(2) Elemental analysis (metal analysis: ICP-AES, CHN analysis: CHN analyzer)
Titanium content: 11% by mass (theoretical value: 11.67% by mass)
C: 64.1% by mass (theoretical value: 64.38% by mass), H: 8.7% by mass (theoretical value: 9.33% by mass), N: 6.1% by mass (theoretical value: 6.83) mass%)

[Production Example 1] Compound No. 1 Preparation of 40 After a mixed solution of 37.4 g of tetrakis (diethylamino) hafnium and 110.6 g of dehydrated toluene was placed in an ice bath in a 300 mL four-necked flask under an Ar atmosphere, 11.1 g of cyclopentadiene was added from an isobaric dropping funnel over about 30 hours. The reaction was carried out dropwise. Subsequently, 18.8 g of 1- (dimethylamino) -2-methyl-2-propanol was added dropwise from an isobaric dropping funnel over about 1 hour and reacted. After completion of the dropwise addition, the temperature was gradually raised to room temperature, and the reaction was further continued for 2 hours. Subsequently, after distilling off the solvent under reduced pressure, a fraction at 60 Pa / 145 to 7 ° C. under reduced pressure was fractionated to obtain a pale yellow liquid compound No. 34.5 g of 40 was obtained.

(Analysis value)
(1) Normal pressure TG-DTA
Mass 50% decrease temperature: 258 ° C. (Ar flow rate: 100 mL / min, temperature increase: 10 ° C./min, sample amount: 10.421 mg)
(2) Elemental analysis (metal analysis: ICP-AES, CHN analysis: CHN analyzer)
Hafnium content: 32.9% by mass (theoretical value: 32.99% by mass)
C: 48.6% by mass (theoretical value: 48.84% by mass), H: 6.7% by mass (theoretical value: 7.08% by mass), N: 4.7% by mass (theoretical value: 5.18) mass%)

[Evaluation Example 1] Evaluation of physical properties of zirconium compound 4. About the comparison compound 1 and the comparison compound 2 shown below, the state of each compound in the normal pressure of 30 degreeC was observed visually. Further, the viscosity at 30 ° C. was measured using a falling ball viscometer (manufactured by Anton Paar, product name: AMVn). Moreover, about the comparative compound 1 and the comparative compound 2, the temperature when weight reduced 50% under a normal pressure using TG-DTA was measured (Ar flow rate: 100 mL / min, temperature rising: 10 degreeC / min, comparative compound) 1 sample amount: 13.644 mg, comparative compound 2 sample amount: 12.485 mg). In addition, samples prepared by heat treatment at a temperature of 10 ° C. from 100 ° C. to 300 ° C. for 1 hour each in an inert gas atmosphere are prepared, and TG-DTA measurement (at normal pressure conditions from the low temperature of the heat treatment) Ar flow rate: 100 mL / min, temperature elevation: 10 ° C./min, measurement temperature range: 25 ° C. to 600 ° C.) were sequentially performed. The temperature of the said heat processing of the first sample in which the quantity of the residue after TG-DTA measurement became 2 mass% or more was made into the "thermal decomposition temperature." The results are shown in Table 1.

  From Table 1 above, Compound No. 4. Comparative compound 1 and comparative compound 2 were both low melting point compounds that were liquid under normal pressure conditions of 30 ° C. In addition, Compound No. Although 4 had a higher viscosity at 30 ° C. than Comparative Compound 1, it was found to be sufficiently low in viscosity as a raw material for chemical vapor deposition. A thin film forming raw material having a low melting point and a low viscosity is a thin film forming raw material that can improve productivity because of its good transportability. In addition, from the results of normal pressure TG-DTA, Compound No. 4 was found to exhibit a vapor pressure sufficient as a raw material for chemical vapor deposition and a very high thermal stability.

[Evaluation Example 2] Evaluation of Physical Properties of Titanium Compound 22. About the comparative compound 3 shown below, the state of each compound in the normal pressure of 30 degreeC was observed visually. For the solid compound, the melting point was measured using a minute melting point measuring apparatus. Further, for Comparative Compound 3, the temperature when the weight was reduced by 50% under normal pressure using TG-DTA was measured (Ar flow rate: 100 mL / min, temperature increase: 10 ° C./min, sample amount: 8.997 mg). ). The results are shown in Table 2.

  From Table 2 above, Comparative Compound 3 is a compound having a melting point of 75 ° C. No. 22 was found to be a low melting point compound that is liquid under normal pressure conditions of 30 ° C. Since the raw material for forming a thin film having a low melting point is easy to transport, the raw material for forming a thin film can improve productivity. In addition, from the results of normal pressure TG-DTA, Compound No. No. 22 showed a vapor pressure sufficient as a raw material for chemical vapor deposition, although the temperature at the time of 50% by mass reduction was slightly higher than that of Comparative Compound 3.

[Example 3] Production of zirconium oxide thin film by ALD method A zirconium oxide thin film was produced on a silicon substrate by ALD using the chemical vapor deposition apparatus shown in FIG. About the obtained thin film, when the film thickness measurement by the X-ray reflectivity method, the thin film structure and the thin film composition were confirmed by the X-ray diffraction method and the X-ray photoelectron spectroscopy, the film thickness was 2 to 4 nm. Is zirconium oxide (confirmed by Zr4d peak by XPS analysis), and the residual carbon content in the thin film was less than 0.1 atom% which is the lower limit of detection. The film thickness obtained per cycle was 0.02 to 0.04 nm.

(conditions)
Reaction temperature (substrate temperature); 250 ° C., reactive gas; ozone (process)
A series of steps consisting of the following (1) to (4) was taken as one cycle and repeated 100 cycles.
(1) Raw material container heating temperature: 150 ° C., raw material container pressure: Chemical vapor deposition raw material vaporized under the conditions of 80 Pa or less is introduced into a film forming chamber and deposited at a system pressure of 80 Pa for 10 seconds.
(2) Unreacted raw materials and by-product gases are removed by argon purging for 10 seconds.
(3) A reactive gas is introduced into the film forming chamber and reacted at a system pressure of 80 Pa for 10 seconds.
(4) Unreacted raw material and by-product gas are removed by argon purge for 10 seconds.

Comparative Example 3 Production of Zirconium Oxide Thin Film by ALD Method Using Comparative Compound 2 (Zr (DMAP) ₄ ) as a raw material for chemical vapor deposition and using the chemical vapor deposition apparatus shown in FIG. By the method, a zirconium oxide thin film was produced on a silicon substrate. About the obtained thin film, when the film thickness measurement by X-ray reflectivity method, the thin film structure and the thin film composition were confirmed by X-ray diffraction method and X-ray photoelectron spectroscopy, the film thickness was 1 nm, and the film composition was oxidized. It was zirconium (confirmed by the Zr4d peak by XPS analysis), and the residual carbon content in the thin film was 5 atom%. The film thickness obtained per cycle was 0.01 nm.

(conditions)
Reaction temperature (substrate temperature); 280 ° C., reactive gas; ozone (process)
A series of steps consisting of the following (1) to (4) was taken as one cycle and repeated 100 cycles.
(1) Raw material container heating temperature: 150 ° C., raw material container pressure: Chemical vapor deposition raw material vaporized under the conditions of 80 Pa or less is introduced into a film forming chamber and deposited at a system pressure of 80 Pa for 10 seconds.
(2) Unreacted raw materials and by-product gases are removed by argon purging for 10 seconds.
(3) A reactive gas is introduced into the film forming chamber and reacted at a system pressure of 80 Pa for 10 seconds.
(4) Unreacted raw material and by-product gas are removed by argon purge for 10 seconds.

  From the results of Example 3, it was found that a very good zirconium oxide thin film can be produced by using the compound of the present invention as a raw material for forming an ALD thin film. On the other hand, from the result of Comparative Example 3, it was found that when Comparative Compound 2 was used as a raw material for forming an ALD thin film, it was difficult to produce a high-quality zirconium oxide thin film including productivity.

[Example 4] Production of titanium oxide thin film by ALD method A titanium oxide thin film was produced on a silicon substrate by the ALD method under the following conditions using the chemical vapor deposition apparatus shown in FIG. About the obtained thin film, when the film thickness measurement by X-ray reflectivity method, the thin film structure and the thin film composition were confirmed by X-ray diffraction method and X-ray photoelectron spectroscopy, the film thickness was 3 to 4 nm. Is titanium oxide (confirmed by the Ti3d peak by XPS analysis), and the residual carbon content in the thin film was less than the detection lower limit of 0.1 atom%. The film thickness obtained per cycle was 0.03 to 0.04 nm.

(conditions)
Reaction temperature (substrate temperature); 300 ° C, reactive gas; ozone (process)
A series of steps consisting of the following (1) to (4) was taken as one cycle and repeated 100 cycles.
(1) Raw material container heating temperature: 160 ° C., raw material container pressure: The raw material for chemical vapor deposition vaporized under the conditions of 80 Pa or less is introduced into the film forming chamber, and is deposited for 10 seconds at a system pressure of 80 Pa.
(2) Unreacted raw materials and by-product gases are removed by argon purging for 10 seconds.
(3) A reactive gas is introduced into the film forming chamber and reacted at a system pressure of 80 Pa for 10 seconds.
(4) Unreacted raw material and by-product gas are removed by argon purge for 10 seconds.

[Example 5] Production of hafnium oxide thin film by ALD method A hafnium oxide thin film was produced on a silicon substrate by ALD using the chemical vapor deposition apparatus shown in FIG. About the obtained thin film, when the film thickness measurement by the X-ray reflectivity method, the thin film structure and the thin film composition were confirmed by the X-ray diffraction method and the X-ray photoelectron spectroscopy, the film thickness was 2 to 4 nm. Is hafnium oxide (confirmed by the Hf4f peak by XPS analysis), and the residual carbon content in the thin film was less than the detection limit of 0.1 atom%. The film thickness obtained per cycle was 0.02 to 0.04 nm.

(conditions)
Reaction temperature (substrate temperature); 300 ° C, reactive gas; ozone (process)
A series of steps consisting of the following (1) to (4) was taken as one cycle and repeated 100 cycles.
(1) Raw material container heating temperature: 150 ° C., raw material container pressure: Chemical vapor deposition raw material vaporized under the conditions of 80 Pa or less is introduced into a film forming chamber and deposited at a system pressure of 80 Pa for 10 seconds.
(2) Unreacted raw materials and by-product gases are removed by argon purging for 10 seconds.
(3) A reactive gas is introduced into the film forming chamber and reacted at a system pressure of 80 Pa for 10 seconds.
(4) Unreacted raw material and by-product gas are removed by argon purge for 10 seconds.

Claims (5)

A compound represented by the following general formula (1).

(Wherein R ^{1 to} R ⁶ each independently represent hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms, and R ⁷ , R ⁸ and R ⁹ are each a straight chain having 1 to 4 carbon atoms. Represents a chain or branched alkyl group, and M ¹ represents zirconium or titanium.)   A raw material for forming a thin film comprising the compound according to claim 1.   A vapor containing a compound obtained by vaporizing the raw material for forming a thin film according to claim 2 is introduced into a film forming chamber in which the substrate is installed, and the compound is decomposed and / or chemically reacted to thereby form the substrate. A method for producing a thin film, wherein a thin film containing zirconium atoms or titanium atoms is formed on the surface. A thin film forming raw material for an atomic layer deposition method comprising a compound represented by the following general formula (2).

(In the formula, each of R ^{11 to} R ¹⁶ independently represents hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms, and R ¹⁷ , R ^18, and R ¹⁹ are each a straight chain having 1 to 4 carbon atoms. Represents a chain or branched alkyl group, and M ² represents zirconium, hafnium or titanium.)   Vapor containing a compound obtained by vaporizing the raw material for forming a thin film according to claim 4 is introduced into a film forming chamber provided with a substrate, and zirconium atoms and hafnium are formed on the surface of the substrate by an atomic layer deposition method. A method for producing a thin film, which forms a thin film containing at least one atom selected from atoms and titanium atoms.

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