Organometallic compound and thin film using the same

Abstract

The organic metal compound and thin film using the same of the present application satisfy high volatility, excellent chemical and thermal stability, and have a significantly improved thin film deposition rate even at low temperatures. Furthermore, it is possible to achieve a thin film having improved deterioration of characteristics due to by-products, excellent step coverage, a high dielectric constant, and an equivalent oxide film thickness (EOT) in electrical terms and a thickness in which a tunnel effect does not occur in physical terms.

Description

[0001] This application is a divisional application of the invention application filed on January 25, 2019, with application number 201980010593.0 (international application number PCT / KR2019 / 001062) and entitled "organometallic compounds and thin films using the same". Technical Field

[0002] This invention relates to an organometallic compound and thin films using the same, and more particularly, to an organometallic compound and thin films using the same that satisfy the requirements of high volatility, excellent chemical and thermal stability, and significantly improved thin film deposition rate even at low temperatures. Background Technology

[0003] Recently, the application of various thin films, such as metals, semiconductors, and oxides, has been investigated for the fabrication of nanoscale integrated devices. During the formation of these various thin films, as devices continue to shrink to extremely small sizes and new forms of devices emerge, the necessity and conformality of thin film deposition processes with nanoscale, composite structures and tunable thickness at the atomic level are increasing. Currently, the gate oxide used in the gate structure of metal-oxide-semiconductor field-effect transistors (MOSFETs), the core of electronic devices, is based on silicon oxide. However, with the nanoscale reduction of device size, problems such as increased leakage current and the formation of gate depletion layers occur. To address these problems, many attempts have been made to utilize novel oxides with high dielectric constants. Among various high dielectric constant oxides, the most studied material is nitrogen-doped HfO2 based on HfO2. x N y and HfSi as a silicate material x O y While these materials have achieved good results in improving charge mobility and reliability, problems still exist in increasing dielectric constant, thermal stability, and interfacial properties. To address these issues, research focuses on the deposition process and properties of high-dielectric-constant thin films using atomic layer deposition (ALD), the development of deposition processes for various high-dielectric-constant materials, the development of new process methods, and their applications in nanodevices.

[0004] As a precursor for depositing metal thin films, metal oxides, or metal nitrides using organometallic chemical vapor deposition or atomic layer deposition, the most representative is metal pentachloride (MCl5 (M = V, Nb, Ta)), a type of metal halide compound. However, these metal pentachlorides have the following problems: 1) as solid compounds with low vapor pressure at room temperature, they are difficult to apply to semiconductor mass production processes due to their low film deposition rate; 2) chloride contamination occurs.

[0005] On the other hand, metal alkoxides are representative precursor compounds used for depositing metal oxides. In particular, those of formula M2(OEt) 10 Metal ethanol oxide precursor compounds (M = Nb, Ta) are most widely used for depositing metal oxide films via MOCVD and ALD processes because they exist as highly volatile liquids at room temperature. However, these metal alkoxide compounds have the following problems: 1) low thermal stability, resulting in reduced step coverage due to precursor decomposition at matrix temperatures above 300°C during deposition; 2) increased carbon contamination.

[0006] Furthermore, metal imino / amide compounds have the following problems: 1) the possible ALD process temperature is below 325°C; 2) the crystallinity of the film is low; 3) the deposited film contains more contaminants such as carbon. In addition, 4) in particular, there is a problem of high leakage current, not only in DRAM processes below 50nm but also in gate and capacitor dielectric materials in the field of flash memory.

[0007] Furthermore, the use of Cu wiring films as wiring films in semiconductor integrated circuits has been expanding in recent years. However, in the formation of Cu wiring films for advanced devices beyond the 32nm node, it is difficult to embed Cu into holes and trenches using current electroplating methods. This is because, under current conditions, the barrier metal film required as the substrate layer of the Cu wiring film is formed by PVD, making it difficult to miniaturize and obtain a satisfactory substrate layer. Therefore, there is a current demand for very thin films with high coverage of holes, trenches, etc., with a large aspect ratio relative to the barrier metal film, as well as high barrier properties. Summary of the Invention

[0008] The problem the invention aims to solve

[0009] The present invention was developed to solve the above-mentioned problems. The purpose of the present invention is to provide an organometallic compound and thin films using the same, which have high volatility, excellent chemical and thermal stability, and significantly improved thin film deposition rate even at low temperatures.

[0010] Solution for solving the problem

[0011] To achieve the above objectives, the organometallic compounds of the present invention may have the structure of the following chemical formula 1.

[0012] [Chemical Formula 1]

[0013]

[0014] In the above chemical formula 1, M is selected from Group 5 transition metals; X a X b and X c Each is independently O, N, P, As, or -P=O; R1, R2, R3, and R4 are independently hydrogen, C, or C. 1-9 Alkyl or heteroalkyl, wherein R1, R2, R3 and R4 above are determined according to X. a X b and X c The existence or non-existence of C depends on its atomic valence; A and B are each independently of C. 1-9 Alkylene or heteroalkylene, the above B according to X b and X c The existence or non-existence of an atom depends on its valence.

[0015] In a preferred embodiment of the present invention, the Group 5 transition metal of the above-mentioned chemical formula 1 may include one of V, Nb and Ta.

[0016] In a preferred embodiment of the present invention, X of the above-mentioned chemical formula 1 a X b and X c Each of these components can be independently O or N; R1, R2, R3, and R4 can each be independently hydrogen or C. 1-6 alkyl.

[0017] In a preferred embodiment of the present invention, A and B of the above-mentioned chemical formula 1 can each be independently C. 1-3 Alkylene or heteroalkylene.

[0018] Furthermore, the organometallic compounds of the present invention, in order to achieve the above objectives, may have the structure of the following chemical formula 2.

[0019] [Chemical Formula 2]

[0020]

[0021] In the above chemical formula 2, M is selected from Group 5 transition metals; X a X b and X c Each is independently O, N, P, As, or -P=O; R1, R2, R3, and R4 are independently hydrogen, C, or C.1-9 Alkyl or heteroalkyl, wherein R1, R2, R3 and R4 above are determined according to X. a X b and X c The presence or absence of an atom depends on its valence; A is C. 1-9 Alkylene or heteroalkylene.

[0022] In a preferred embodiment of the present invention, the Group 5 transition metal of the above-mentioned chemical formula 2 can be one of V, Nb, and Ta, and the above-mentioned X a X b and X c Each of these components can be independently O or N; R1, R2, R3, and R4 can each be independently hydrogen or C. 1-6 Alkyl group, where A can be C. 1-3 Alkylene or heteroalkylene.

[0023] Furthermore, the organometallic compounds of the present invention, in order to achieve the above objectives, may have the structure of the following chemical formula 3.

[0024] [Chemical Formula 3]

[0025]

[0026] In the above chemical formula 3, M is selected from Group 5 transition metals; X a and X c Each is independently O, N, P, As, or -P = O; X b It is N, P, As, or -P=O; R1 and R3 are each independently hydrogen, C 1-9 Alkyl or heteroalkyl, wherein R1 and R3 above are based on X a and X c The existence or non-existence of C depends on its atomic valence; A and B are each independently of C. 1-9 Alkylene or heteroalkylene.

[0027] In a preferred embodiment of the present invention, the Group 5 transition metal of the above-mentioned chemical formula 3 can be one of V, Nb, and Ta, and the above-mentioned X a and X c Each can be independently O or N, X b It can be N, and R1 and R3 above can each be hydrogen or C independently. 1-6 Alkyl group, where A and B above can each be C independently. 1-3 Alkylene or heteroalkylene.

[0028] Furthermore, the organometallic compounds of the present invention, in order to achieve the above objectives, may have the structure of the following chemical formula 4.

[0029] [Chemical Formula 4]

[0030]

[0031] In the above chemical formula 4, M includes Nb or Ta.

[0032] Another object of the present invention is to provide a metal-containing thin film for semiconductors, the metal-containing thin film for semiconductors being prepared by using one or more organometallic compounds selected from chemical formulas 1 to 4 as precursors.

[0033] Furthermore, another object of the present invention is to provide a semiconductor structure comprising a metal-containing thin film for use in semiconductors.

[0034] Brief explanations are provided for the terms used in this specification.

[0035] The term "alkyl" refers to an aliphatic hydrocarbon group. An alkyl group can be a "saturated alkyl" that does not include any alkene or alkyne group. An alkyl group can also be an "unsaturated alkyl" that includes at least one alkene or alkyne group. The term "alkene" refers to a group with at least two carbon atoms bonded by at least one carbon-carbon double bond, while the term "alkyne" refers to a group with at least two carbon atoms bonded by at least one carbon-carbon triple bond. Whether saturated or unsaturated, the alkyl group can be branched, straight-chain, or cyclic. Furthermore, "alkyl" includes both substituted and unsubstituted alkyl groups.

[0036] Unless otherwise stated, the terms "substituted or unsubstituted" mean both cases where the substituents are substituted and cases where the substituents are not substituted. Substitution includes substituents selected individually and independently from alkyl, acyl, cycloalkyl (including bicycloalkyl and tricycloalkyl), perhaloalkyl, aryl, heteroaryl, heterocycloalkyl, hydroxyl, alkoxy, azide, amino, ketone, ether, amide, ester, triazole, isocyanate, arylalkoxy, aryloxy, mercapto, alkylthio, arylthio, cyano, halogen, carbonyl, thiocarbonyl, O-carbamoyl, N-carbamoyl, O-thiocarbamoyl, N-thiocarbamoyl, C-amide, N-amide, S-sulfonamide, N-sulfonamide, etc. The invention includes the substitution of one or more functional groups in the following groups: C-carboxyl, O-carboxyl, isocyanate, cyanothio, isothiocyanate, nitro, silyl, trihalomethanesulfonyl, pyrrolidone, pyrrolidine, piperidine, piperazine, morpholine, amino, amino, amide, halogen, thiol, aldehyde, carbonyl, phosphorus, sulfur, phosphate, phosphate ester, phosphite, sulfate, disulfide, oxygen, mercapto, amine group including mono- and poly-substituted amine groups, and their protected derivatives. However, the invention is not limited thereto and includes all cases in which they are substituted by various substituents commonly used in the art. Depending on the circumstances, they may also be substituted or unsubstituted.

[0037] The term "heteroatoms" refers to atoms other than carbon and hydrogen.

[0038] The term "heteroalkyl" refers to a form in which at least one carbon atom of an alkyl group is replaced by another heteroatom.

[0039] The term "according to valence" means satisfying the valence. "Satisfying the valence" means introducing a certain number of electrons into the outermost shell of an atom, so that the bonded atoms exist in the most stable state.

[0040] The effects of the invention

[0041] The organometallic compounds of the present invention and the thin films utilizing them exhibit high volatility, excellent chemical and thermal stability, and significantly improved film deposition rates even at low temperatures. Furthermore, thin films with improved property degradation due to byproducts, excellent step coverage, high dielectric constant, electrically equivalent oxide thickness (EOT), and physically free from tunneling effects can be achieved. Attached Figure Description

[0042] Figure 1a and Figure 1b The Map-Nb01 prepared in Example 1 are respectively 1 H-NMR and 13 C-NMR measurement data.

[0043] Figure 2aand Figure 2b The Map-Ta01 prepared in Example 2 are respectively 1 H-NMR and 13 C-NMR measurement data. Detailed Implementation

[0044] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings to enable those skilled in the art to easily implement the present invention. However, the above embodiments are provided only to help better understand the present invention, and the scope of the present invention is not limited to the above embodiments.

[0045] As mentioned above, existing metal pentachlorides, metal-alkoxide compounds, or metal-imide / amide compounds are solid compounds with low vapor pressure at room temperature. Therefore, they are difficult to apply to semiconductor mass production processes due to their low thin film deposition rate. Furthermore, they have low thermal stability, resulting in reduced step coverage due to precursor decomposition at high substrate temperatures during deposition. In addition, they cause significant contamination in the process and the deposited thin film, leading to problems with low process reliability and efficiency.

[0046] Therefore, the present invention provides an organometallic compound having the structure of the following chemical formula 1 to explore a method for solving the above-mentioned problems. The above-mentioned organometallic compound satisfies high volatility, excellent chemical and thermal stability, and exhibits a significantly improved thin film deposition rate even at low temperatures. Furthermore, it can achieve thin films that improve property degradation caused by byproducts, have excellent step coverage, high dielectric constant, electrically equivalent oxide film thickness (EOT), and are physically free from tunneling effects.

[0047] Organometallic compounds having the structure of the following chemical formula 1.

[0048] [Chemical Formula 1]

[0049]

[0050] In the above chemical formula 1, M is selected from Group 5 transition metals; X a X b and X c Each is independently O, N, P, As, or -P=O; R1, R2, R3, and R4 are independently hydrogen, C, or C. 1-9 Alkyl or heteroalkyl, wherein R1, R2, R3 and R4 above are determined according to X. a X b and X c The existence or non-existence of C depends on its atomic valence; A and B are each independently of C. 1-9 Alkyl or heteroalkyl, B above according to X b and X c The existence or non-existence of an atom depends on its valence.

[0051] The M mentioned above is a Group 5 transition metal, which is one of V, Nb and Ta. Preferably, it can be one of V, Nb and Ta, and more preferably, it can be Nb or Ta.

[0052] R1, R2, R3, and R4 are each independently hydrogen and C. 1-9 Alkyl or heteroalkyl, wherein R1, R2, R3 and R4 above are determined according to X. a X b and X c The presence or absence of atoms depends on their valence. Furthermore, R1, R2, R3, and R4 can each exist or not exist independently; if they exist, it means that R1, R2, R3, and R4 are each independently hydrogen, C, or C. 1-9 Alkyl or heteroalkyl.

[0053] The above X a X b and X c Independently defined as O, N, P, As, or -P = O, this can mean X a X b and X c Each can be the same as or different from the others, selected from O, N, P, As, and -P=O.

[0054] Furthermore, R1, R2, R3, and R4 are each independently hydrogen and C. 1-9 Alkyl or heteroalkyl, wherein R1, R2, R3 and R4 above are determined according to X. a X b and X c The existence or non-existence of R1, R2, R3, and R4 depends on their atomic valence, meaning that each of these atoms exists or does not exist independently, to satisfy X. a X b and X c The valence of the atom. R1, R2, R3, and R4, as mutually different substituents, can all be present or not present, meaning that any one or more can exist, and any one or more can not exist. Specifically, when R1, R2, R3, and R4 exist independently, this means that R1, R2, R3, and R4 can be chosen as the same or different substituents. For example, when X... a When the value is N, R1 exists, and when X... a When the value is 0, R1 does not exist.

[0055] Furthermore, the existence of R2, R3, and R4 depends not only on X. b and X c The valence of an atom can also depend on the presence or absence of B. For example, when X b Let N, X cWhen N is present and B exists, R2 does not exist; one of R3 and R4 exists while the other does not exist. Furthermore, as another example, when X... b Let N, X c If the value is O, then when B exists, R2, R3, and R4 do not exist.

[0056] Furthermore, A and B above are each independently C. 1-9 Alkylene or heteroalkylene, the above B according to X b and X c The presence or absence of an atom with a certain valence means that A and B can be chosen to be the same or different substituents, and B can satisfy X. b and X c The atomic valence exists or does not exist. For example, when X b When X is 0, B does not exist. Furthermore, whether the existence of B depends on X is not solely dependent on X. b and X c The valence of an atom can also depend on the presence or absence of R2, R3, and R4. For example, when X b Let N, X c When X is 0, R2 and R3 exist, and R4 does not exist, then B does not exist. Conversely, when X... b Let N, X c B exists when R2, R3, and R4 are all absent (0).

[0057] As described above, R1, R2, R3, R4, and X are determined without restriction within the aforementioned range based on the presence and type of each substituent. a X b and X c Does B exist? On the other hand, does the aforementioned C... 1-9 Heteroalkyl does not refer to heteroalkyl with 1 to 9 carbon atoms, but rather to heteroalkyl with 1 to 9 carbon atoms and heteroatoms. In other words, it refers to heteroalkyl with a total number of 1 to 9 carbon atoms and heteroatoms.

[0058] Furthermore, the heteroatom in the heteroalkyl group can be any atom that can bond with a carbon atom in the alkyl group to form a stable substituent; preferably, the heteroatom in the heteroalkyl group can be N, O, or S. The number of heteroatoms is not limited as long as it contains at least one carbon atom and can form a stable organometallic compound. When the total number of carbon atoms and heteroatoms is 7 to 9, preferably, the number of carbon atoms can be 1 to 8, more preferably, 1 to 4. When the total number of carbon atoms and heteroatoms is 3 to 6, preferably, the number of carbon atoms can be 1 to 5, more preferably, 1 to 2.

[0059] According to a preferred embodiment of the present invention, the above-mentioned X aX b and X c Each of these components can be independently O or N; R1, R2, R3, and R4 can each be independently hydrogen or C. 1-6 Alkyl group. More preferably, the above-mentioned X a X b and X c It can be N, and R1, R2, and R4 can each be hydrogen or C independently. 1-3 Alkyl group, R3 can be C 4-6 alkyl.

[0060] According to a preferred embodiment of the present invention, A and B can each be independently C. 1-3 Alkyl or heteroalkyl. More preferably, A and B can each be C. 1-3 Alkylene, most preferably, A and B can each be C 1-2 Alkylene.

[0061] The descriptions of the various substitution units of chemical formulas 2 to 5 in this specification are consistent with the descriptions of the same substitution units of chemical formula 1 above. Therefore, the following descriptions will only repeat the content described above.

[0062] Furthermore, in order to solve the above problems, the present invention provides an organometallic compound having the structure of the following chemical formula 2.

[0063] [Chemical Formula 2]

[0064]

[0065] In the above chemical formula 2, M is selected from Group 5 transition metals; X a X b and X c Each is independently O, N, P, As, or -P=O; R1, R2, R3, and R4 are independently hydrogen, C, or C. 1-9 Alkyl or heteroalkyl, wherein R1, R2, R3 and R4 above are determined according to X. a X b and X c The presence or absence of an atom depends on its valence; A is C. 1-9 Alkylene or heteroalkylene.

[0066] Furthermore, the aforementioned Group 5 transition metal can be one of V, Nb, and Ta, and the aforementioned X a X b and X c Each of these components can be independently O or N; R1, R2, R3, and R4 can each be independently hydrogen or C. 1-6 Alkyl group, where A can be C. 1-3Alkyl or heteroalkyl groups. More preferably, the aforementioned Group 5 transition metal can be Nb or Ta, and the aforementioned X... a X b and X c Each of them can be N independently, and R1, R3, and R4 can each be hydrogen or C independently. 1-3 Alkyl group, wherein R2 can be C2. 3-6 Alkyl group. More preferably, R1, R3, and R4 can each be independently C1. 1-2 Alkyl group, wherein R2 can be C2. 4-5 alkyl.

[0067] The above R1, R2, R3 and R4 are based on X a X b and X c The presence or absence of an atom with a certain valence means that R1, R2, R3, and R4 can exist or not exist independently, to satisfy X. a X b and X c The valence of the atom. Furthermore, R1, R2, R3, and R4, as mutually different substituents, can or can not exist, meaning that any one or more of R1, R2, R3, and R4 can exist while any one or more can not exist. Specifically, when R1, R2, R3, and R4 exist independently, R1, R2, R3, and R4 can be chosen to be the same or different substituents. For example, when X... a When the value is N, R1 exists, and when X... a When the value is 0, R1 does not exist.

[0068] Furthermore, in order to solve the above problems, the present invention provides an organometallic compound having the structure of the following chemical formula 3.

[0069] [Chemical Formula 3]

[0070]

[0071] In the above chemical formula 3, M is selected from Group 5 transition metals; X a and X c Each is independently O, N, P, As, or -P = O; X b It is N, P, As, or -P=O; R1 and R3 are each independently hydrogen, C 1-9 Alkyl or heteroalkyl, wherein R1 and R3 above are based on X a and X c The existence or non-existence of C depends on its atomic valence; A and B are each independently of C. 1-9 Alkylene or heteroalkylene.

[0072] According to a preferred embodiment of the present invention, the aforementioned Group 5 transition metal can be one of V, Nb, and Ta, and the aforementioned X a and X c Each can be independently O or N, X b It can be N, and R1 and R3 above can each be hydrogen or C independently. 1-6 Alkyl group, where A and B above can each be C independently. 1-3 Alkylene or heteroalkylene. More preferably, the aforementioned Group 5 transition metal can be Nb or Ta, and the aforementioned X a X b and X c Both can be N, and R1 and R3 can each be hydrogen or C independently. 1-3 Alkyl group, where A and B above can each be C independently. 1-3 Alkylene. More preferably, R1 and R3 can each be independently C1. 1-2 Alkyl group, where A and B above can each be C independently. 1-2 Alkylene.

[0073] Furthermore, the present invention can provide organometallic compounds having the structure of the following chemical formula 4.

[0074] [Chemical Formula 4]

[0075]

[0076] In the above chemical formula 4, M is Nb or Ta.

[0077] Furthermore, the aforementioned organometallic compounds can be widely used in fields where they are commonly used, and preferably, they can be included or used in the preparation of semiconductor materials in the semiconductor field. More preferably, they can be used to prepare semiconductor metal thin films.

[0078] Specifically, the aforementioned organometallic compounds can be used as precursors for forming thin films contained in semiconductors. A precursor refers to a substance in a stage before it becomes a specific substance during metabolism or reaction. Thin films for semiconductors can be formed by physically / chemically adsorbing the aforementioned organometallic compound precursors onto a substrate.

[0079] Furthermore, when used as a precursor, the organometallic compound of the present invention can be directly contained in the metal-containing thin film, or its final shape can change during the process. That is, when the organometallic compound of the present invention is used as a precursor to prepare a thin film contained in a semiconductor, its final shape can be of a wide variety of shapes.

[0080] In other words, the present invention provides metal-containing thin films comprising the compounds described in the embodiments, and provides metal-containing thin films prepared by using one or more of the above-mentioned organometallic compounds as precursors. Such thin films exhibit excellent uniformity and improved step-coating characteristics, thus possessing the advantage of significantly high efficiency.

[0081] Furthermore, the present invention provides a semiconductor structure comprising the aforementioned metal thin film. This semiconductor structure possesses excellent physical properties and is manufactured using a highly efficient thin film, thus offering advantages such as greater stability and improved efficiency.

[0082] On the other hand, in this regard, the present invention provides a method for preparing a metal-containing thin film, the method comprising: step a) providing a vapor comprising the above-mentioned various types of organometallic compounds; and step b) reacting the vapor with a substrate according to a deposition method to form a metal-containing complex layer on at least one surface of the substrate.

[0083] Using the above-described preparation method not only improves substrate adsorption efficiency and safety during substrate formation, but also increases film deposition rate, thereby shortening process time. Furthermore, it reduces process contamination, allows for use over a wider temperature range, and significantly improves the reliability and efficiency of the manufacturing process. In addition, the above preparation method yields films with good uniformity and improved stepped coating characteristics.

[0084] The present invention will now be described in detail, except for the content that is repeated above.

[0085] First, step a) of providing one or more vapors contained in the aforementioned organometallic compound is described.

[0086] The evaporation of the metal supply source is achieved by introducing a carrier gas into a heated container containing the organometallic compound of the present invention as a metal supply source. Preferably, the container is heated at a temperature at which the metal supply source can be obtained at a sufficient vapor pressure. The carrier gas may be selected from Ar, He, H2, N2, or mixtures thereof. The metal supply source in the container may be mixed with a solvent or another metal supply source, or a mixture thereof. Preferably, the container may be heated at a temperature in the range of 25°C to 200°C, and the amount of the evaporating precursor may be adjusted by adjusting the temperature of the container. To control the evaporation level in the container, the pressure in the container may be varied. The evaporation level of the metal supply source may be increased by reducing the pressure in the container. Preferably, the pressure in the container may be varied in the range of 1 Torr to 800 Torr.

[0087] Furthermore, the aforementioned metal supply source can be supplied to an evaporator where evaporation occurs in a liquid state. The aforementioned metal supply source may or may not be mixed with a solvent. Furthermore, the aforementioned metal supply source may be mixed with another metal supply source. The mixture of the aforementioned metal supply sources may be mixed with a solvent or a solvent mixture. The aforementioned metal supply source may be mixed with a stabilizer. The aforementioned solvent may be selected from the group consisting of alkanes such as hexane, heptane, and octane; aromatic solvents such as benzene, toluene, mesitylene, and xylene; silicon-containing solvents such as hexamethyldisiloxane, hexamethyldisilazane, and tetramethylsilane; sulfur-containing solvents such as dimethyl sulfoxide; and oxygen-containing solvents such as tetrahydrofuran and dioxane. On the other hand, as the concentration of the mixed solution including the aforementioned solvents, preferably, the content of the aforementioned metal supply source may be from 50% by weight to 99.9% by weight.

[0088] Next, step b) is described, in which the vapor is reacted with the substrate according to the deposition method to form a metal-containing complex layer on at least one surface of the substrate.

[0089] The vaporized metal supply source is introduced into the reaction chamber, where it comes into contact with the substrate surface. The substrate can be heated at a sufficient growth rate and a temperature adequate for obtaining a desired film with the desired physical state and composition. This heating temperature is typically the temperature used to obtain the desired film, preferably in the range of 100°C to 700°C, more preferably 450°C or lower. Alternatively, the process can be assisted by a non-limiting choice of plasma technology to improve the reactivity of the vaporized metal supply source and / or the reactivity of other types of gases used in the process.

[0090] On the other hand, in step b) above, the deposition method is not limited as long as it can form a metal complex layer on the surface of the substrate. Preferably, chemical vapor deposition (CVD) or atomic layer deposition (ALD) can be used.

[0091] First, atomic layer deposition (ALD) is a method for growing thin films by alternately injecting a metal-containing raw material and a reactive gas; that is, it is a method of growing an atomic-unit thin film by reacting the raw material with the gas and repeating this process to adjust the film thickness. Specifically, after injecting the organometallic compound according to the invention as a precursor into the evaporator, it can be transferred to the chamber in the vapor phase. The vaporized film-forming composition can be transferred to the chamber. In this case, the precursor material can be transferred using a method of transporting the volatile gas using vapor pressure, a direct liquid injection method, or a liquid delivery system (LDS) that dissolves the precursor material in an organic solvent for transport. In this case, preferably, the transport gas or dilution gas used to move the precursor material onto the substrate can be one or more inert gases selected from Ar, N2, He, and H2, more preferably selected from Ar or N2. On the other hand, preferably, the N2 canister flow rate can be in the range of 30 sccm to 5000 sccm, more preferably in the range of 50 sccm to 300 sccm.

[0092] Next, the transferred precursor material can be adsorbed onto the substrate, and any unadsorbed precursor material is purged. An inert gas can be used as the purging gas. Next, reactants can be supplied. Reaction products can include oxidants such as H₂O, H₂O₂, O₂, O₃, N₂O, etc. The reactants and the adsorbed precursor material can react to form a metal-containing thin film, which may include zirconium, titanium, or hafnium. Then, unreacted material is purged. As a result, excess reactants and generated byproducts can be removed.

[0093] On the other hand, the adsorption step, purging, reaction product supply step, and purging described above are performed as a unit cycle. To form a film of the desired thickness, the unit cycle can be repeated. Preferably, it can be repeated 10 to 10,000 times.

[0094] Furthermore, when using the above-described atomic layer deposition method, preferably, the temperature can be between 100°C and 450°C, more preferably, it can be in the range of 150°C to 350°C. Preferably, the pulse period in the ALD can be between 1 second and 10 seconds, and preferably, the pressure can be between 0.01 Torr and 800 Torr.

[0095] Secondly, chemical vapor deposition (CVD) is a method of forming a thin film on a substrate by supplying a gas containing elements constituting the material to be formed onto the substrate through chemical reactions such as pyrolysis, photolysis, redox reactions, and substitution in the gas phase or on the substrate surface. When using the above-mentioned chemical vapor deposition method, preferably, the temperature can be from 100°C to 700°C, more preferably, from 200°C to 500°C. Furthermore, preferably, the pressure can be from 0.01 Torr to 800 Torr, more preferably, from 1 Torr to 200 Torr. Furthermore, preferably, the carrier gas can be N2, He, Ar, or H2, more preferably, selected from Ar or N2. Preferably, the N2 flow rate can be from 30 sccm to 300 sccm, more preferably, from 50 sccm to 100 sccm.

[0096] Furthermore, the present invention provides a composition and a method for preparing a metal-containing thin film using the above composition, wherein the composition comprises 0.1% to 99.9% of one or more compounds among the above organometallic compounds and includes residual amounts of one or more organic compounds selected from saturated or unsaturated hydrocarbons, cyclic ethers, noncyclic ethers, esters, alcohols, cyclic amines, noncyclic amines, cyclic sulfides, noncyclic sulfides, phosphines, β-diketones, and β-chitosan esters.

[0097] When metal-containing thin films are prepared using compositions containing the aforementioned organometallic compounds, the substrate adsorption efficiency and safety of the compounds are improved, while the processing time is shortened. Furthermore, since the physical properties and composition of the prepared thin film can be adjusted by regulating the content of the aforementioned composition, thin films suitable for specific purposes and means can be easily prepared.

[0098] Furthermore, barrier metal films with high coverage, extreme thinness, and high barrier properties can be prepared by using compositions containing the aforementioned organometallic compounds.

[0099] As a result, the present invention provides novel organometallic compounds that 1) not only improve the reliability and efficiency of the manufacturing process, 2) also achieve further improvements in chemical and thermal stability, and 3) achieve significantly improved thin film deposition rates even at low temperatures. Furthermore, the superior organometallic compounds described above can be used to prepare metal-containing semiconductor thin films, thereby providing metal-containing thin films for semiconductors and semiconductor structures comprising the same, exhibiting improved performance degradation caused by byproducts, excellent step coverage, high dielectric constant, electrically equivalent oxide film thickness (EOT), and physically free from tunneling effects.

[0100] The present invention will now be described in more detail based on embodiments. However, the following embodiments are intended only to facilitate understanding of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0101] [Example]

[0102] Example 1 (Nb)

[0103] (1) Preparation of the synthesized novel compounds

[0104] [Reaction Formula 1]

[0105]

[0106] After dissolving 17 g of dimethylamine in toluene, the solution was added dropwise to 141 mL of a 2.5 M butyllithium solution at -20 °C and stirred at room temperature for 2 hours to obtain lithium dimethylamine (yield: 90%). After dissolving 32.7 g of tert-amylamine in toluene, 22.5 mL of trichlorosilane was added dropwise, and the mixture was stirred for 15 minutes. Then, after passing the reaction product through diatomaceous earth, the product was added dropwise to a reaction vessel containing 21.8 g of niobium chloride dissolved in toluene, and the mixture was stirred for 1 hour. 25 mL of pyridine was added dropwise, and the mixture was stirred for 12 hours. The product was then passed through diatomaceous earth, and the solvent was removed under reduced pressure to obtain tert-amylamine niobium chloride (TANbCl). TANbCl was then dissolved in toluene, and dimethylamine was added dropwise at -20 °C, and the mixture was refluxed for 4 hours. The product was then passed through diatomaceous earth, and the solvent was removed under reduced pressure. The reaction product was then purified under reduced pressure at 0.1 torr and 100 °C to give niobium dimethylamine (Nb-DMA) (yield: 57.9%). Next, 14.5 g of niobium-dimethylamine (Nb-DMA) was dissolved in toluene, and 5.76 g of cyclopentadienylethylmethylamine was added dropwise at -20 °C. After stirring for 1 hour, the solvent was removed by reduced pressure distillation to give cyclopentadienylethylmethylamide niobium(V)formamide tertiary amide (Map-Nb01) (yield: 44%).

[0107] The prepared Map-Nb01 1 H-NMR and 13 CNMR measurement data are shown in Figure 1a and Figure 1b middle.

[0108] (2-1) Preparation of metal-containing thin films using the above-mentioned Map-NbO1 as a precursor (Example 1-1)

[0109] A silicon wafer was immersed in a piranha solution prepared by mixing sulfuric acid (H2SO4) and hydrogen peroxide water (H2O3) in a 4:1 volume ratio for 10 minutes and then removed. The wafer was then immersed in a dilute HF aqueous solution for 2 minutes to form a pure silicon surface. An NbN film was then deposited using the aforementioned Map-NbO1 as a precursor via plasma atomic layer deposition (PEALD). The substrate temperature was heated to 300°C to 450°C, and the precursor was diluted with octane in a stainless steel container to adjust the viscosity to 4 cps to 10 cps, followed by evaporation via an evaporator. The precursor was supplied to the reactor for 5 to 20 seconds, and the ammonia gas flow rate as a reducing agent was 100 sccm, with the supply time adjusted to 5 to 20 seconds.

[0110] After supplying the precursor and ammonia, argon gas, used as a purification gas, was added for 30 seconds. It can be seen that the thin film preparation process using MAP-NbO1 as the precursor and ammonia as the reducing agent exhibits ALD characteristics. Furthermore, the deposition rate is approximately... / Cycle, film density is 3.6 g / cm³ 3 This results in a thin film with an Nb:Nat ratio close to 1:1 and carbon content less than 1.0%. The lower velocity is due to the extended purging time.

[0111] Both carbon content and resistivity depend on the addition of ammonia. When the ammonia flow rate is 25 sccm, the film contains almost no carbon, but when ammonia is absent, the carbon content is equal to or greater than 30 at% (atomic concentration percentage).

[0112] (2-2) Preparation of metal-containing thin films using the above-mentioned Map-NbO1 as a precursor (Examples 1-2)

[0113] A silicon wafer was immersed in a piranha solution prepared by mixing sulfuric acid (H2SO4) and hydrogen peroxide water (H2O3) in a 4:1 volume ratio for 10 minutes and then removed. The wafer was then immersed in a dilute HF aqueous solution for 2 minutes to form a pure silicon surface. Nb2O5 thin films were then deposited using the aforementioned Map-NbO1 as a precursor via atomic layer deposition (ALD). The substrate temperature was heated to 150°C to 400°C, and the precursor was diluted with octane in a stainless steel container to adjust the viscosity to 4 cps to 10 cps, followed by evaporation via an evaporator. The precursor was supplied to the reactor for 3 to 7 seconds, and the flow rate of ozone as an oxidant was 500 sccm, with the supply time adjusted to 3 to 7 seconds.

[0114] After supplying the precursor and ozone, argon gas, used as a purifying gas, is added for 5 to 7 seconds. It can be seen that the thin film preparation process using MAP-NbO1 as the precursor and ozone as the oxidant exhibits ALD characteristics. Furthermore, the deposition rate is approximately... / Cycle, film density is 4.4 g / cm³ 3 This resulted in a thin film with an Nb:Oat% ratio close to 2:5 and carbon content less than 1.0%.

[0115] Example 2 (Ta)

[0116] (1) Preparation of the synthesized novel compounds

[0117] [Reaction 2]

[0118]

[0119] After dissolving 17 g of dimethylamine in toluene, the solution was added dropwise to 141 mL of a 2.5 M butyllithium solution at -20 °C and stirred at room temperature for 2 hours to obtain lithium dimethylamine (yield: 90%). After dissolving 32.7 g of tert-amylamine in toluene, 22.5 mL of trichlorosilane was added dropwise, and the mixture was stirred for 15 minutes. Then, after passing the reaction product through diatomaceous earth, the reaction product was added dropwise to a reaction vessel containing 28.66 g of tantalum chloride dissolved in toluene, and the mixture was stirred for 1 hour. Subsequently, 20 mL of pyridine was added dropwise, and the mixture was stirred for 12 hours. The reaction product was then passed through diatomaceous earth, and the solvent was removed under reduced pressure to obtain tert-amylamine tantalum chloride (V) (TATaCl). TATaCl was then dissolved in toluene, and 13.5 g of dimethylamine was added dropwise at -20 °C, and the mixture was refluxed for 4 hours. The reaction product was then passed through diatomaceous earth, and the solvent was removed under reduced pressure. The reaction product was then purified under reduced pressure at 0.1 torr and 100 °C to give tantalum dimethylamine (Ta-DMA) (yield: 30%). Subsequently, 9.48 g of tantalum dimethylamine (Ta-DMA) was dissolved in toluene, and 2.93 g of cyclopentadienylethylmethylamine was added dropwise at -20 °C. After stirring for 1 hour, the solvent was removed by reduced pressure distillation to give cyclopentadienylethylmethylamide tantalum(V)methylamide cymoxanilamide (Map-Ta01) (yield: 20%).

[0120] The prepared Map-Ta01 1 H-NMR and 13 CNMR measurement data are shown in Figure 2a and 2b middle.

[0121] (2) Using the above-mentioned Map-Ta01 as a precursor to prepare metal-containing thin films

[0122] A silicon wafer was immersed in a piranha solution prepared by mixing sulfuric acid (H2SO4) and hydrogen peroxide water (H2O3) in a 4:1 volume ratio for 10 minutes and then removed. The wafer was then immersed in a dilute HF aqueous solution for 2 minutes to form a pure silicon surface. Using the aforementioned Map-Ta01 as a precursor, a TaN thin film was deposited via plasma atomic layer deposition (PEALD). The substrate temperature was heated to 300°C to 450°C, and the precursor was diluted with octane to adjust the viscosity to 4 cps to 10 cps. The precursor was then transferred to an evaporator in a stainless steel container for evaporation. The precursor was supplied to the reactor for 5 to 20 seconds, and the ammonia gas flow rate as a reducing agent was 25 sccm to 100 sccm, with the supply time adjusted to 5 to 20 seconds. After supplying the precursor and ammonia, argon gas was added as a purifying gas for 30 seconds. It can be seen that the thin film preparation process using MAP-TaO1 as a precursor and ammonia as a reducing agent exhibits ALD characteristics. Furthermore, the deposition rate is approximately... / Cycle, film density is 6.45 g / cm³ 3 .

[0123] This resulted in a film with a Ta:N atomic percentage close to 1:1 and carbon content less than 1.0%. The lower velocity was due to the extended purging time. Although the films deposited at 300°C to 375°C during tantalum nitride deposition were nitrogen-rich, their resistivity was quite low (12000 μΩ·cm at an NH3 flow rate of 25 sccm), clearly indicating the presence of TaN, and therefore could be considered as the TaN phase rather than Ta3N5. Both the carbon content and resistivity depended on the addition of ammonia. When the ammonia flow rate was 25 sccm, the film contained almost no carbon, but when ammonia was absent, the carbon content was equal to or greater than 30 at%.

[0124] Examples 3 to 15

[0125] Except for using organometallic compounds having the structure of the following chemical formula 5 and whose substituents are determined according to Tables 1 to 3 as precursors, the rest were carried out in the same manner as in Example 1.

[0126] [Chemical Formula 5]

[0127]

[0128] Furthermore, the compounds synthesized in Examples 1 to 15 described above and used as precursors are as follows. Here, '1' in the following chemical formulas represents the compound of Example 1, and so on, each compound corresponds to each example in turn.

[0129] [Chemical Formula]

[0130]

[0131] Table 1

[0132]

[0133]

[0134] Table 2

[0135]

[0136]

[0137] Table 3

[0138] M Nb <![CDATA[X a ]]> N <![CDATA[X b ]]> N <![CDATA[X c ]]> O <![CDATA[R1]]> <![CDATA[-CH3]]> <![CDATA[R2]]> Does not exist <![CDATA[R3]]> Does not exist <![CDATA[R4]]> Does not exist A <![CDATA[-(CH2)4-]]> B <![CDATA[-(CH2)4-]]>

[0139] Experimental Example 1 - Determination of Thin Film Deposition Rate

[0140] For the films prepared according to Examples 1 to 15 above, the film deposition rate for each ALD cycle was measured. The results are shown in Table 4 below.

[0141] Experiment Example 2 - Evaluating the Improvement Effect of Step Coverage Characteristics

[0142] The improvement effect on the stepped coverage characteristics of the films prepared according to Examples 1 to 15 above was evaluated. The results are shown in Table 4 below.

[0143] Experimental Example 3 - Evaluation of the Purity Improvement Effect in Deposited Thin Films

[0144] Auger electron spectroscopy (AES) was used to analyze the composition of the films prepared according to Examples 1 to 15 to measure the content of carbon and nitrogen, which are sources of contamination within the films. The results are shown in Table 4 below.

[0145] Table 4

[0146]

[0147] As shown in Table 4 above, the film deposition rates of the films prepared using the organometallic compounds of the present invention as precursors are all greater than 0.35 ( / cycle), that is, it has a significantly improved value. It can be seen that even when alkyl groups with shorter chain lengths, such as heteroalkyl or methyl, are substituted as shown in Examples 10 to 13, the film deposition rate is equal to or greater than 0.40 ( ( / cycle), which means excellent.

[0148] Furthermore, it can be seen that the film step coverage is also greater than 92%, indicating a significant improvement. It can be seen that even as shown in Examples 4 to 9, X... a X b and X c For O, P, As or -P=O other than nitrogen, the thin film step coverage is equal to or greater than 94.6%, which is excellent.

[0149] Furthermore, in the case of film purity, the amount of carbon, which is also a source of contamination, is 1.3 at% or less. Therefore, it can be seen that the amount of residual impurities in the present invention is very low, thereby providing a film with improved purity.

Claims

1. An organometallic compound, characterized in that, It has the structure of the following chemical formula 2: [Chemical Formula 2] In the above chemical formula 2, M is selected from one of V, Nb, and Ta; X a and X b Each can be independently O or N, X c The oxygen is O; R1, R2, R3 and R4 are each independently hydrogen or carbon. 1-6 Alkyl groups, R1, R2, R3 and R4 above, according to X a X b and X c The presence or absence of an atom depends on its valence; A is C. 1-3 Alkylene.

2. The organometallic compound according to claim 1, characterized in that, The M mentioned above is selected from one of V, Nb, and Ta; X a and X b The N is N; R1, R2, R3 and R4 above are each independently hydrogen or C. 1-6 Alkyl; A is C 1-3 Alkylene.

3. The organometallic compound according to claim 2, characterized in that, The M mentioned above represents Nb.

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