Group 5 metal precursor compound for thin film deposition and method of forming thin film containing group 5 metal using the same

Abstract

According to an embodiment of the present invention, the Group 5 metal precursor compound is represented by the following chemical formula 1: Thus, the advantages of the Group 5 metal precursor compound according to an embodiment of the present invention are its excellent thermal stability, its liquid state at room temperature, and its high volatility, which is beneficial for its application in thin film formation processes. Furthermore, when using the Group 5 metal precursor compound according to an embodiment of the present invention, Group 5 metal thin films with low residue content and uniform properties can be obtained, and the thickness of the thin film can be easily adjusted.

Description

Group 5 Metal Precursor Compounds for Thin Film Deposition and Method for Forming a Thin Film Containing a Group 5 Metal Using the Same The present invention relates to a group 5 metal precursor compound and a method for forming a thin film containing a group 5 metal using the same. More specifically, the present invention relates to a group 5 metal compound and a method for forming a thin film containing a group 5 metal using the same, which can form a thin film containing a group 5 metal having excellent thermal stability, a low growth rate per cycle (GPC) of the thin film during a deposition process, and a high residue content. With the development of electronic technology, the demand for miniaturization and weight reduction of electronic components for various electronic devices is rapidly increasing. To form fine electronic components, various physical and chemical deposition methods have been proposed, and various studies on preparing various electronic components such as metal thin films, metal oxide thin films, or metal nitride thin films using such deposition methods are underway. In the manufacture of semiconductor devices, a thin film containing a group 5 metal compound is usually formed by a metal organic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) process. However, compared with the MOCVD deposition process, the advantage of the ALD deposition process is that due to a self-limiting reaction, the step coverage is excellent, and since it is a relatively low-temperature process, it can avoid a decrease in device performance due to thermal diffusion. To deposit a thin film containing vanadium (V), niobium (Nb), or tantalum (Ta) among group 5 metal compounds, it is very important to select a precursor compound suitable for the deposition process. Currently, there are various group 5 metal precursors in the semiconductor industry. Conventional group 5 metal precursor compounds have a low thermal stability and are easily decomposed during a thin film formation process, and thus have a disadvantage of a high carbon content in the thin film. In addition, since the growth rate per cycle (GPC) of the thin film is high, it is not easy to finely adjust the thickness, and thus it is difficult to form a thin film containing a group 5 metal required for next-generation semiconductor devices. [Technical Problem to be Solved] An object of the present invention is to provide a group 5 metal compound that is suitable for thin film growth, has a stable thermal stability, a high vapor pressure, and exists in a liquid state at room temperature, thereby solving the process problems caused by using a conventional group 5 metal compound. In addition, an object of the present invention is to provide a Group 5 metal compound for thin film deposition, and by using the Group 5 metal compound, a high-quality and uniform thin film with a low carbon content can be provided. In addition, an object of the present invention is to provide a method for forming a thin film containing a Group 5 metal, and the thickness can be precisely adjusted by using the Group 5 metal composition for thin film deposition. The subject matter of the present invention is not limited to the above-mentioned subject matter, and other unmentioned subject matters can be clearly understood by those skilled in the art according to the following description. [Technical Solution] An embodiment of the present invention provides a Group 5 metal composition represented by the following Chemical Formula 1. [Chemical Formula 1] (In Chemical Formula 1, M is any one selected from Group 5 metal elements, and R 1 is selected from a linear alkyl group having 1 to 4 carbon atoms and a branched alkyl group having 3 to 4 carbon atoms, and R 2 and R 3 are each independently selected from a linear alkyl group having 1 to 6 carbon atoms and a branched alkyl group having 3 to 6 carbon atoms, and X is each independently selected from halogen elements.) Another embodiment of the present invention provides a precursor composition for depositing a thin film containing a Group 5 metal element, and the precursor composition for thin film deposition according to an embodiment of the present invention includes a Group 5 metal element compound represented by the Chemical Formula 1. Yet another embodiment of the present invention provides a method for forming a thin film containing a Group 5 metal, the method using the Group 5 metal precursor compound represented by the Chemical Formula 1, and depositing a thin film on a substrate by a Metal Organic Chemical Vapor Deposition (MOCVD) process or an Atomic Layer Deposition (ALD) process. The specific content of other embodiments is included in the detailed description and the drawings. [Advantageous Effects] The Group 5 metal compound according to an embodiment of the present invention has the advantages of excellent thermal stability, existing in a liquid state at room temperature, and having a high vapor pressure, so that the deposition process is beneficial to the thin film. In particular, compared with the Group 5 metal precursor compound having a conventional amine ligand, the Group 5 metal precursor compound of the present invention has a lower growth rate per cycle (GPC) of the thin film during deposition. Therefore, when forming a thin film by an MOCVD deposition process or an ALD deposition process, a high-quality Group 5 metal thin film with a low carbon content can be formed, and fine thickness adjustment can be easily performed, so that a thin film with a target thickness can be easily formed. When performing an ALD deposition process using the Group 5 metal precursor compound according to an embodiment of the present invention, compared with a conventional Group 5 metal precursor compound, it has a constant thin film growth rate in a larger temperature range, so that the quality of the thin film can be further improved. In addition, according to an embodiment of the present invention, compared with a conventional Group 5 metal compound having an M-Cl (M is any one selected from Group 5 metal elements) ligand, the Group 5 metal compound including an asymmetric disubstituted cyclopentadiene ligand has the advantages of being more conducive to liquefaction and having excellent thermal stability, so that the process of forming a Group 5 metal thin film is easy. In addition, the Group 5 metal thin film formed by the Group 5 metal compound according to an embodiment of the present invention has excellent thermal stability, excellent morphological characteristics, and because of its low diffusivity, low leakage, and low charge trapping properties, it can be used for various purposes such as dielectrics, barrier films, and electrodes. The effects according to the present invention are not limited to the content of the above examples, and more different effects are included in the present invention. The advantages, features, and methods for realizing them of the present invention can be clarified with reference to the accompanying drawings and the embodiments described in detail below. However, the present invention is not limited to the embodiments disclosed below, but is implemented in various different shapes. Only these embodiments are intended to fully disclose the present invention and are provided to fully inform those with ordinary knowledge in the technical field to which the present invention belongs of the scope of the invention. The present invention is only defined by the scope of the claims. When describing the present invention, if it is judged that the specific description of related conventional technologies may unnecessarily obscure the key points of the present invention, its detailed description will be omitted. If terms such as "including", "having", "forming", etc. mentioned in the present invention are used, unless "only" is used, other parts can be added. If a component is expressed in the singular, unless there is a particularly clear description, it includes the plural. When explaining components, even if there is no separate clear description, it can be interpreted as including an error range. In the entire specification of this application, the term "room temperature" refers to a temperature of 15°C to 30°C, or 20°C to 27°C. The Group 5 metal precursor compound according to an embodiment of the present application may be represented by Chemical Formula 1. [Chemical Formula 1] In Chemical Formula 1, M is any one selected from Group 5 metal elements, and R 1 is selected from a linear alkyl group having 1 to 4 carbon atoms and a branched alkyl group having 3 to 4 carbon atoms, and R 2 and R 3 are each independently selected from a linear alkyl group having 1 to 6 carbon atoms and a branched alkyl group having 3 to 6 carbon atoms, and X is each independently selected from halogen elements. Hereinafter, the compound of Chemical Formula 1 will be specifically described. In Chemical Formula 1, M may be any one selected from Group 5 metal elements. For example, M may be any one selected from niobium (Nb), tantalum (Ta), and vanadium (V). Preferably, for example, it may be Nb or Ta. More preferably, M may be Nb. At this time, the thermal stability of the precursor compound is excellent and the residue content is small, so a high-quality thin film can be provided. In Chemical Formula 1, R 1 may be any one selected from a linear alkyl group having 1 to 4 carbon atoms and a branched alkyl group having 3 to 4 carbon atoms. For example, R 1 may be a branched alkyl group having 3 to 4 carbon atoms. At this time, the thermal stability is more excellent and the vapor pressure is high. Therefore, in the thin film formation process, the precursor compound does not solidify but can exist in a liquid state. In Chemical Formula 1, R 2 and R 3 may each independently be any one selected from a linear alkyl group having 1 to 6 carbon atoms and a branched alkyl group having 3 to 6 carbon atoms. As described above, when the cyclopentadiene ligand is substituted by the substituents R 2 and R 3 compared with the Group 5 metal compound including an unsubstituted cyclopentadiene ligand, the binding force between the Group 5 metal and the ligand compound may be reduced. Thus, the content of unnecessary residues in the thin film formed by the deposition process can be reduced. Preferably, in Chemical Formula 1, R 2 and R 3 may each be a linear alkyl group having 1 to 6 carbon atoms. At this time, the content of unnecessary residues in the thin film during the deposition process is further reduced, so that a high-quality metal thin film can be provided. In Chemical Formula 1, R 2 and R 3 may be different from each other. As described above, when the substituents R 2 and R 3 bonded to the cyclopentadiene ligand are of an asymmetric structure that is different from each other, the melting point of the precursor compound is lowered and it can exist in a liquid state at room temperature, whereby a Group 5 metal thin film with high reproducibility and uniform physical properties can be formed. According to an embodiment of the present invention, when R 2 and R 3 are Group 5 metal compounds substituted with different alkyl groups, R 2 and R 3 in which one of them is a Group 5 metal compound with an asymmetric structure having a hydrogen atom has the characteristic of a relatively high vapor pressure. In addition, under the condition that the sum of the number of carbon atoms of R 2 is the same as the sum of the number of carbon atoms of R 3 As described in one embodiment, when R 2 and R 3 are Group 5 metal compounds with an asymmetric structure that is different from each other, compared with the case where R 2 and R 3 are Group 5 metal compounds with the same symmetric structure, it has a higher vapor pressure. Therefore, a high-quality Group 5 metal thin film can be easily formed by the deposition process. In Chemical Formula 1, the number of carbon atoms of R 2 and the number of carbon atoms of R 3The sum of the number of carbon atoms of may be less than or equal to 3. At this time, the thermal stability is excellent, the vapor pressure is high, and it can exist in a liquid state at room temperature. Therefore, it is easy to form a Group 5 metal thin film by a deposition process. In Chemical Formula 1, if R 2 the number of carbon atoms of and R 3 when the sum of the number of carbon atoms of is greater than 3, although the Group 5 metal compound can exist in a liquid state at room temperature, it may exhibit a relatively high viscosity characteristic. Therefore, from the viewpoint of process ease and formation of a high-quality Group 5 metal thin film, in Chemical Formula 1, R 2 the number of carbon atoms of and R 3 the sum of the number of carbon atoms of may be less than or equal to 3. In Chemical Formula 1, X may each independently be a halogen element. Specifically, for example, X may each independently be any one selected from fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). Preferably, for example, X may each be chlorine (Cl). Regarding a conventional precursor compound similar to MCl 5 (where M is any one selected from Group 5 metals), it is composed only of M-X (X is a halogen element and may be any one selected from fluorine (F), chlorine (Cl), bromine (Br), and iodine (I)), which has a greater bond energy than the M-N bond and the N-C bond. Thus, the thermal stability is excellent, but the residue content is high, and it exists as a solid at room temperature. Therefore, the problem is that it is not easy to perform the deposition process and the film quality is non-uniform. The Group 5 metal precursor compound according to an embodiment of the present invention includes M-X and M=N bonds, and cyclopentadiene substituted by two substituents is bonded to the M central metal. Therefore, compared with a conventional Group 5 metal precursor, the thermal stability is excellent, it exists in a liquid state at room temperature, so it is easy to perform the deposition process, and a Group 5 metal thin film with uniform and homogeneous physical properties can be formed. More specifically, the Group 5 metal compound may be selected from the compounds represented by the following Chemical Formula 2, Chemical Formula 3, and Chemical Formula 4. [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] In Chemical Formula 2, Chemical Formula 3, and Chemical Formula 4, M may each independently be any one selected from the Group 5 metal elements niobium (Nb), tantalum (Ta), and vanadium (V). More preferably, the Group 5 metal compound may be a compound represented by Chemical Formula 2 below. Its advantages are that the thermal stability is very excellent and the residue content is less, so that a Group 5 metal thin film with excellent physical properties can be provided, and the film growth rate (Growth Per Cycle, GPC) is low, so that the thickness control is easy. The Group 5 metal compound represented by Chemical Formula 1 according to an embodiment of the present invention exists in a liquid state at room temperature, so it is easy to store and handle, and can be advantageously applied to the formation of a thin film by a deposition process. Therefore, the Group 5 metal compound represented by Chemical Formula 1 according to an embodiment of the present invention can be used as a precursor for a Group 5 metal thin film prepared by a MOCVD deposition process or an ALD deposition process. In addition, for the Group 5 metal compound represented by Chemical Formula 1, a constant film growth rate (Growth Per Cycle, GPC) is exhibited in a relatively large temperature range during the deposition process. The advantages are that the film growth rate (Growth Per Cycle, GPC) is low, so that the thickness adjustment is easy, and fine thickness adjustment can be achieved. Therefore, the Group 5 metal compound represented by Chemical Formula 1 can be used as a precursor composition for depositing a thin film containing a Group 5 metal. Hereinafter, a method for forming a thin film containing a Group 5 metal according to an embodiment of the present invention will be described in detail. The method for forming a thin film containing a Group 5 metal uses the above-mentioned Group 5 metal compound, and the repeated description of the Group 5 metal compound is omitted. In the method for forming a thin film containing a Group 5 metal according to an embodiment of the present invention, a Group 5 metal precursor compound represented by Chemical Formula 1 is used, and a thin film is deposited on a substrate by a deposition process. The deposition process can be achieved by an atomic layer deposition (ALD) process or a chemical vapor deposition (CVD) process, such as a metal organic chemical vapor deposition (MOCVD) process. The deposition process can be carried out at 50 to 700 °C. First, the Group 5 metal precursor compound represented by Chemical Formula 1 is transferred onto the substrate. For example, the Group 5 metal precursor compound can be supplied to the substrate by a bubbling method, a vapor phase mass flow controller method, a direct gas injection (Direct Gas Injection, DGI) method, a direct liquid injection (Direct Liquid Injection, DLI) method, a liquid transfer method in which it is dissolved in an organic solvent and transferred, etc., but it is not limited thereto. Optionally, the Group 5 metal precursor compound can be supplied together with a carrier gas or a diluent gas. The carrier gas is not reactive with the Group 5 metal precursor compound and is lighter than the Group 5 metal precursor compound, so that it is easy to transfer the vaporized Group 5 metal precursor compound to the reaction chamber. The diluent gas is not reactive with the Group 5 metal precursor compound, so that side reactions are not triggered, and by controlling its flow rate, reactions such as the growth rate of the thin film can be easily controlled. For example, the carrier gas and the diluent gas can each be selected from argon (Ar), nitrogen (N 2 ), helium (He), and hydrogen (H 2 ). For example, the Group 5 metal precursor compound can be mixed with a carrier gas or a diluent gas containing one or more selected from argon (Ar), nitrogen (N 2 ), helium (He), and hydrogen (H 2 ), and then transferred to the substrate by the bubbling method or the direct gas injection method. In the deposition process for forming a Group 5 metal thin film, a reaction gas can be supplied as needed to form various Group 5 metal-containing thin films such as a Group 5 metal oxide thin film, a Group 5 metal carbon oxide thin film, and a Group 5 metal nitride thin film. The reaction gas can be supplied in the step of depositing the thin film. For example, the reaction gas can include one or more selected from water vapor (H 2 O), oxygen (O 2 ), ozone (O 3 ), hydrogen peroxide (H 2 O 2 ), ammonia (NH 3 ), hydrazine (N 2 H 4 ), nitrous oxide (N 2 O), and nitrogen (N 2 ). For example, when preparing a Group 5 metal oxide thin film or a Group 5 metal carbon oxide thin film, a reaction gas containing oxygen can be provided. For example, the oxygen-containing reaction gas can include one or more selected from water vapor (H 2 O), oxygen (O 2 ), oxygen plasma, ozone (O 3 ) and hydrogen peroxide (H 2 O 2 ), or one or more of them. Such a reaction gas can react with a Group 5 metal compound in a thin film deposition process to form a Group 5 metal oxide thin film or a Group 5 metal carbon oxide thin film. For another example, when preparing a Group 5 metal nitride thin film, a reaction gas containing nitrogen can be provided. For example, the nitrogen-containing reaction gas can include one or more selected from ammonia (NH 3 ), hydrazine (N 2 H 4 ), nitrous oxide (N 2 O) and nitrogen gas (N 2 ). Such a reaction gas can react with a Group 5 metal compound in a thin film deposition process to form a Group 5 metal nitride thin film. After the Group 5 metal precursor compound of Chemical Formula 1 is supplied onto a substrate, if heat energy, plasma, electric bias, etc. are applied, the decomposition and condensation reactions of the Group 5 metal precursor compound are carried out, and a thin film containing the Group 5 metal is thereby formed. If a thin film with a target thickness is to be formed, the following steps may be included: purging an inert gas such as argon (Ar), nitrogen (N 2 ), helium (He) and / or hydrogen (H 2 ) into the reaction chamber to remove the unreacted remaining Group 5 metal precursor compound. The Group 5 metal thin film prepared by the method for forming a thin film according to an embodiment of the present invention can effectively reduce the amount of residues, thereby providing a high-quality thin film. In addition, the method for forming a thin film according to an embodiment of the present invention exhibits a constant thin film growth rate within a relatively large thin film growth temperature range, thereby enabling the provision of a Group 5 metal thin film with more uniform physical properties, and the thin film growth rate is low, thereby enabling fine thickness control. Hereinafter, the Group 5 metal precursor compound according to the present invention will be described in more detail by the following examples. However, this is only for the purpose of facilitating the understanding of the present invention, and the present invention is not limited by the following examples. [Example 1] After injecting 68.2 g (0.252 mol, 1 equivalent) of niobium tetrachloride NbCl 5 and 500 mL of dichloromethane into a flame-dried 1000 mL Schlenk flask, it was stirred at room temperature. 49.9 g (0.278 mol, 1.1 equivalents) of (EtMeCp)Si(Me) was added dropwise to the flask below -20 °C 3 After that, the reaction solution was stirred at room temperature for 12 hours. Then the solvent was removed under reduced pressure to obtain a dark red solid compound represented by (EtMeCp)Nb(Cl) 4 After that, after injecting 55.4 g (0.757 mol, 3 equivalents) of tert-butylamine, the reaction solution was stirred at room temperature for 12 hours. Then the solvent was removed under reduced pressure, 300 mL of hexane was injected and stirred for 1 hour. Then, in order to separate the substances dissolved in hexane, it was filtered and then subjected to distillation under reduced pressure to obtain 28.3 g of a red liquid compound. By nuclear magnetic hydrogen spectrum analysis ( 1 1H NMR) confirmed the synthesis of the niobium precursor compound (tBuN)Nb(EtMeCp)(Cl) represented by the following Chemical Formula 2a 2 . [Chemical Formula 2a] [Example 2] After injecting 68.2 g (0.252 mol, 1 equivalent) of niobium tetrachloride NbCl 5 and 500 mL of dichloromethane into a flame-dried 1000 mL Schlenk flask, it was stirred at room temperature. 53.8 g (0.278 mol, 1.1 equivalents) of (nPrMeCp)Si(Me) was added dropwise to the flask below -20 °C 3 After that, the reaction solution was stirred at room temperature for 12 hours. Then the solvent was removed under reduced pressure to obtain (nPrCp)Nb(Cl) 4 The represented dark red solid compound. Subsequently, after injecting 55.4 g (0.757 mol, 3 equivalents) of tert-butylamine, the reaction solution was stirred at room temperature for 12 hours. Subsequently, the solvent was removed under reduced pressure, and 300 mL of hexane was injected and stirred for 1 hour. Subsequently, in order to separate the substances dissolved in hexane, after filtration, distillation under reduced pressure was performed to obtain 24.3 g of a red liquid compound. By nuclear magnetic hydrogen spectrum analysis ( 1 1H NMR) confirmed the synthesis of the niobium precursor compound (tBuN)Nb(nPrMeCp)(Cl) represented by the following Chemical Formula 3a 2 . [Chemical Formula 3a] [Example 3] After injecting 68.2 g (0.252 mol, 1 equivalent) of niobium tetrachloride NbCl 5 and 500 mL of dichloromethane into a flame-dried 1000 mL Schlenk flask, it was stirred at room temperature. Dropwise add 53.8 g (0.278 mol, 1.1 equivalents) of (Et 2 Cp)Si(Me) 3 to the flask below -20 °C, and then the reaction solution was stirred at room temperature for 12 hours. Subsequently, the solvent was removed under reduced pressure to obtain a dark red solid compound represented by (Et 2 Cp)Nb(Cl) 4 . Subsequently, after injecting 55.4 g (0.757 mol, 3 equivalents) of tert-butylamine, the reaction solution was stirred at room temperature for 12 hours. Subsequently, the solvent was removed under reduced pressure, and 300 mL of hexane was injected and stirred for 1 hour. Subsequently, in order to separate the substances dissolved in hexane, after filtration, distillation under reduced pressure was performed to obtain 21.5 g of a red liquid compound. By nuclear magnetic hydrogen spectrum analysis ( 1 1H NMR) confirmed the synthesis of the niobium precursor compound (tBuN)Nb(Et 2 Cp)(Cl) 2 . [Chemical Formula 4a] [Example 4] After injecting 90.3 g (0.252 mol, 1 equivalent) of tantalum tetrachloride TaCl 5 and 500 mL of dichloromethane into a flame-dried 1000 mL Schlenk flask, it was stirred at room temperature. 49.9 g (0.278 mol, 1.1 equivalents) of (EtMeCp)Si(Me) was added dropwise to the flask at a temperature below -20 °C 3 After that, the reaction solution was stirred at room temperature for 12 hours. Then, the solvent was removed under reduced pressure to obtain a dark red solid compound represented by (EtMeCp)Nb(Cl) 4 After injecting 55.4 g (0.757 mol, 3 equivalents) of tert-butylamine, the reaction solution was stirred at room temperature for 12 hours. Then, the solvent was removed under reduced pressure, and 300 mL of hexane was injected and stirred for 1 hour. Then, in order to separate the substances dissolved in hexane, it was filtered and then subjected to distillation under reduced pressure to obtain 22.3 g of a light yellow liquid compound. By nuclear magnetic hydrogen spectrum analysis ( 1 1H NMR), the synthesis of the tantalum precursor compound (tBuN)Ta(EtMeCp)(Cl) represented by the following Chemical Formula 2b was confirmed 2 . [Chemical Formula 2b] [Comparative Example 1] In a flame-dried 1000 mL Schlenk flask, 500 mL of toluene was injected into 65.0 g (0.241 mol, 1 equivalent) of niobium tetrachloride NbCl 5 and 78.7 g (0.577 mol, 2.4 equivalents) of zinc chloride ZnCl 2 . After that, 52.8 g (0.722 mol, 3 equivalents) of tert-butylamine was added dropwise at a temperature below -20 °C, and then stirred at room temperature for 4 hours. Then, 45.5 g (0.505 mol, 2.1 equivalents) of dimethoxyethane (ethylene glycol dimethyl ether (1,2-Dimethoxethane)) was added dropwise at a temperature below -20 °C, and the reaction solution was stirred at room temperature for 12 hours. Subsequently, 466 ml (0.746 mol, 3.1 equivalents) of a 1.6 M solution of lithium dimethylamine dissolved in tetrahydrofuran was added dropwise to the flask at a temperature below -20°C. After that, the reaction solution was stirred at room temperature for 12 hours. Then, 17.5 g (0.265 mol, 1.1 equivalents) of cyclopentadiene was added dropwise at a temperature below -20°C, and the reaction solution was stirred at room temperature for 12 hours. To separate the substances dissolved in the solvent, filtration was carried out followed by distillation under reduced pressure to obtain 23.4 g of a yellow liquid compound. By nuclear magnetic resonance hydrogen spectrum analysis ( 1 1H NMR), the synthesis of the niobium precursor compound (tBuN)Nb(Cp)(DMA) represented by Chemical Formula 5 below was confirmed. 2 [Chemical Formula 5] [Comparative Example 2] After injecting 68.2 g (0.252 mol, 1 equivalent) of niobium tetrachloride NbCl 5 and 500 mL of dichloromethane into a flame-dried 1000 mL Schlenk flask, the mixture was stirred at room temperature. At a temperature below -20°C, 49.9 g (0.278 mol, 1.1 equivalents) of (EtMeCp)Si(Me) was added dropwise to the flask. 3 After that, the reaction solution was stirred at room temperature for 12 hours. Then, the solvent was removed under reduced pressure to obtain a dark red solid compound represented by (EtMeCp)Nb(Cl). 4 After that, 66.0 g (0.757 mol, 3 equivalents) of tert-amylamine was injected, and the reaction solution was stirred at room temperature for 12 hours. Then, the solvent was removed under reduced pressure, 300 mL of hexane was injected, and the mixture was stirred for 1 hour. To separate the substances dissolved in hexane, filtration was carried out followed by distillation under reduced pressure to obtain 30.4 g of a red liquid compound. By nuclear magnetic resonance hydrogen spectrum analysis ( 1 1H NMR), the synthesis of the niobium precursor compound (t-AmylN)Nb(EtMeCp)(Cl)- 2 was confirmed. [Chemical Formula 6] [Comparative Example 3] ​After injecting 68.2 g (0.252 mol, 1 equivalent) of niobium tetrachloride NbCl 5 and 500 mL of dichloromethane into a flame-dried 1000 mL Schlenk flask, the mixture was stirred at room temperature. While maintaining the temperature below -20 °C, 49.9 g (0.278 mol, 1.1 equivalents) of (PrCp)Si(Me) 3 was added dropwise to the flask. Then, the reaction solution was stirred at room temperature for 12 hours. After that, the solvent was removed under reduced pressure to obtain a dark red solid compound represented by (PrCp)Nb(Cl) 4 . Subsequently, after injecting 55.4 g (0.757 mol, 3 equivalents) of tert-butylamine, the reaction solution was stirred at room temperature for 12 hours. Then, the solvent was removed under reduced pressure, and 300 mL of hexane was injected and stirred for 1 hour. After that, to separate the substances dissolved in hexane, filtration was carried out followed by distillation under reduced pressure to obtain 27.1 g of a red liquid compound. The synthesis of the niobium precursor compound (tBuN)Nb(PrCp)(Cl) 1 represented by Chemical Formula 7 below was confirmed by 1H NMR analysis. 2 [Chemical Formula 7] [Experimental Example] 1. Thermal Stability Evaluation To understand the thermal stability of each compound according to Example 1 and Comparative Example 1, 0.7 ml of the compound of Example 1 was added to three high-pressure reactors respectively, and 0.7 ml of the compound of Comparative Example 1 was added to three high-pressure reactors respectively to prepare samples. The samples of Example 1 and Comparative Example 1 were heated in an oven at 170 °C, 180 °C, and 200 °C for 1 hour and then cooled to room temperature. Photographs of the samples cooled at room temperature are shown in Figure 2. Referring to Figure 2, for the Group 5 metal precursor compound of Example 1, it was confirmed that there was no color change at 170 °C, and there was a slight color change at 180 °C and 200 °C. In contrast, for the Group 5 metal precursor compound of Comparative Example 1, it was confirmed that the color was darker than at room temperature at 170 °C, darker at 180 °C, and became even darker, approaching black, at 200 °C. The Group 5 metal precursor of Example 1 contains an M-Cl bond, which has a greater bond energy than the M-N bond contained in the Group 5 metal precursor of Comparative Example 1. From this, it can be judged that the Group 5 metal precursor compound of Example 1 contains an M-Cl bond with a greater bond energy compared to the Group 5 metal precursor compound of Comparative Example 1, and thus exhibits higher thermal stability. 2. Thermogravimetric analysis In order to understand the thermal properties of the respective compounds according to Examples 1 to 4 and Comparative Examples 1 to 3, thermogravimetric analysis (TGA) was performed. First, the thermogravimetric analysis equipment was stored in a nitrogen glove box where the moisture and oxygen contents were maintained below 1 ppm. After placing 10 mg of the sample in a crucible, it was heated from 35 °C to 350 °C at a temperature of 10 °C / min while measuring simultaneously. The mass loss of the sample was monitored as a function of the crucible temperature. The results are shown in Table 1 and Tables 3 to 7. FIG. 3 is a chart showing the results of thermogravimetric analysis (TGA) of the Group 5 metal precursor compound according to Example 1, FIG. 4 is a chart showing the results of thermogravimetric analysis (TGA) of the Group 5 metal precursor compound according to Comparative Example 1, FIG. 5 is a chart showing the results of thermogravimetric analysis (TGA) of the Group 5 metal precursor compound according to Comparative Example 2, FIG. 6 is a chart showing the results of thermogravimetric analysis (TGA) of the Group 5 metal precursor compound according to Comparative Example 3, and FIG. 7 is a chart showing the results of thermogravimetric analysis (TGA) of the Group 5 metal precursor compound according to Example 4. [Table 1] Referring to Table 1 and FIGS. 3 to 7 simultaneously, it can be confirmed that the thermal decomposition temperature of each Group 5 metal compound precursor according to Examples 1 to 4 is higher than that of each Group 5 metal compound precursor according to Comparative Examples 1 to 3. From this, it can be seen that the thermal stability of the compounds of Examples 1 to 4 is more excellent than that of the comparative examples. In particular, it can be confirmed that the thermal stability of the compounds of Examples 1 to 3 containing niobium metal elements is more excellent than that of Example 4 containing tantalum metal elements. In addition, referring to FIGS. 3 to 7, it can be confirmed that the residue content of the Group 5 metal precursor compounds prepared according to Example 1, Example 4, Comparative Example 1, Comparative Example 2, and Comparative Example 3 that did not volatilize at temperatures above 350°C is approximately less than 4 wt%. Compared with the residue content of the compounds according to Comparative Examples 1 to 3, the residue content of the compounds according to Example 1 and Example 4 is less. In addition, referring to FIGS. 3 and 7, it can be confirmed that when the types of ligands are the same, compared with the compound of Example 4 containing tantalum metal, the compound of Example 1 containing niobium metal has better thermal stability and less residue content. In addition, it can be confirmed that although the difference in vapor pressure between the compound of Example 1 and the compound of Comparative Example 1 is not significant, the thermal decomposition temperature of the compound of Example 1 is about 30°C higher than that of the compound of Comparative Example 1. In addition, comparing the results of Example 1 and Comparative Example 2, it can be confirmed that in Chemical Formula 1, R 1 is a tert-butylamine group having 4 carbon atoms, it has a higher vapor pressure and a higher thermal decomposition temperature compared to a compound having a tert-amylamine group having 5 carbon atoms. In addition, for each of the compounds of Example 1 and Comparative Example 3, although the total number of carbon atoms of the substituents substituted in cyclopentadiene is the same at 4, as in Example 1, when methyl and ethyl are asymmetrically bonded to cyclopentadiene, compared with the compound having only a propyl group bonded as shown in Comparative Example 3, it has a higher vapor pressure and a higher thermal decomposition temperature. In addition, although the total number of carbon atoms of the compounds of Example 1 and Example 3 is the same at 4, for Example 1, it is a structure in which methyl and ethyl are asymmetrically bonded to cyclopentadiene, and for Example 3, it is a structure in which two ethyl groups are bonded to cyclopentadiene. Comparing the results of Example 1 and Example 3, it can be confirmed that the thermal decomposition temperature of Example 3 is higher than that of Example 1, but Example 1 satisfies both the thermal decomposition temperature and the vapor pressure, making it more advantageous in the process. In addition, it can be confirmed that the two substituents of the compounds of Example 1 and Example 3 are asymmetrically bonded to cyclopentadiene, which is the same. However, the compound of Example 1 in which the total number of carbon atoms of the substituents bonded to cyclopentadiene is 3 satisfies both the thermal decomposition temperature and the vapor pressure, and is more advantageous in the process. In addition, it can be confirmed that the viscosity of the compound of Example 1 in which the total number of carbon atoms of the substituents bonded to cyclopentadiene is 3 is 32.15 cP, while the viscosity of the compound of Example 2 in which the total number of carbon atoms of the substituents bonded to cyclopentadiene is 4 is as high as 84.33 cP. From this, it can be seen that the compound of the example in which the total number of carbon atoms of the substituents bonded to cyclopentadiene is 3 and the two substituents bonded to cyclopentadiene have an asymmetric structure has a lower viscosity, which is more advantageous in the deposition process. 3. Thin film deposition property The growth rate of the thin film during the atomic layer deposition process using each Group 5 metal precursor compound according to Example 1, Example 4, and Comparative Example 1 was analyzed. The results are shown in FIGS. 1 and 8. First, FIG. 1 is a chart showing the growth rate per cycle (Growth Per Cycle, GPC) of the thin film according to the deposition temperature when the niobium precursor compounds according to Example 1 and Comparative Example 1 are used for the atomic layer deposition process, respectively. The deposition conditions were as follows: after filling the niobium precursor compounds according to Example 1 and Comparative Example 1 into a canister, heating was performed at 110° C., and ozone (O 3 ) was used as an oxidant. A silicon wafer was used as the reaction substrate, and deposition was performed by heating from 250° C. to 400° C. After introducing the pulse of the precursor for 10 seconds, argon (Ar) was purged for 10 seconds. Then, after introducing the pulse of ozone (O 3 ) into the reaction chamber for 15 seconds, argon (Ar) was purged for 10 seconds. 80 to 100 cycles were performed in this way. In this way, Group 5 metal oxide thin films of the same thickness were formed by each precursor. Referring to FIG. 1, it can be confirmed that in the atomic layer deposition process, when the niobium precursor compound according to Example 1 is used, the growth rate of the thin film is lower than that when the Group 5 metal precursor compound according to Comparative Example 1 is used, and the growth rate of the thin film remains constant within a large temperature range. In the atomic layer deposition process, the growth rate of the thin film remaining constant means that side reactions such as incomplete reaction, deposition of the precursor state without chemical reaction, or decomposition due to heat do not occur, but the thin film is stably formed. In other words, it can be seen from FIG. 1 that when the Group 5 metal precursor compound according to Example 1 is used, a stable thin film deposition process can be performed compared to when the Group 5 metal precursor compound according to Comparative Example 1 is used. In particular, when using the Group 5 metal precursor compound according to Example 1, an almost constant thin film growth rate is exhibited within the deposition temperature range, so that a Group 5 metal thin film with more excellent physical property uniformity can be obtained. It can be judged that the Group 5 metal precursor compound of Example 1 represented by Chemical Formula 2a contains an M-Cl bond, thereby forming a more stable structure than the compound of Comparative Example 1 containing an M-N bond. FIG. 8 is a graph showing the growth rate (Growth Per Cycle, GPC) of a thin film according to the deposition temperature when performing an atomic layer deposition process using the Group 5 metal precursor compound according to Example 4. The deposition conditions were as follows: after filling the Group 5 metal precursor compound of Example 4 represented by Chemical Formula 2b into a can, heating was performed at 110° C., and ozone (O 3 ) was used as an oxidant. A silicon wafer was used as the reaction substrate, and deposition was performed by heating from 300° C. to 550° C. After introducing a pulse of the precursor for 3 seconds, argon (Ar) was purged for 15 seconds. Then, after introducing a pulse of ozone (O 3 ) into the reaction chamber for 3 seconds, argon (Ar) was then purged for 15 seconds. 100 cycles were performed in this way. Referring to FIG. 8, it can be confirmed that when performing an atomic layer deposition process using the precursor compound represented by Chemical Formula 2b according to Example 4, the growth rate of the thin film remains constant within a large temperature range. In particular, it can be confirmed that, compared with the compound of Comparative Example 1 shown in FIG. 1 above, even above 500° C., the growth rate of the thin film is relatively low and constant. From this, it can be seen that when using the precursor compound represented by Chemical Formula 2b according to Example 4, an almost constant thin film growth rate is exhibited within the deposition temperature range, so that a Group 5 metal thin film with more excellent physical property uniformity can be obtained. It can be judged that the Group 5 metal precursor compound of Example 4 represented by Chemical Formula 2b contains an M-Cl bond, thereby forming a stable structure. The Group 5 metal precursor compound according to various embodiments of the present invention, the precursor composition for depositing a thin film containing a Group 5 metal, and the method for forming a thin film containing a Group 5 metal can be described as follows. A precursor compound containing a Group 5 metal according to an embodiment of the present invention is represented by the following Chemical Formula 1. [Chemical Formula 1] In Chemical Formula 1, M is any one selected from the Group 5 metal elements niobium (Nb), tantalum (Ta), and vanadium (V), and R 1 is selected from a linear alkyl group having 1 to 4 carbon atoms and a branched alkyl group having 3 to 4 carbon atoms, and R 2 and R 3 Each independently is selected from a linear alkyl group having 1 to 6 carbon atoms and a branched alkyl group having 3 to 6 carbon atoms, and each X is independently a halogen element. According to another feature of the present invention, in Chemical Formula 1, R 1 can be a branched alkyl group having 3 to 4 carbon atoms, and R 2 and R 3 can each be a linear alkyl group having 1 to 6 carbon atoms. According to yet another feature of the present invention, R 2 and R 3 can be different from each other. According to yet another feature of the present invention, the sum of the number of carbon atoms of R 2 and the number of carbon atoms of R 3 can be less than or equal to 3. According to yet another feature of the present invention, the Group 5 metal precursor compound can be selected from the compounds represented by the following Chemical Formula 2, Chemical Formula 3, and Chemical Formula 4. [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] In Chemical Formula 2, Chemical Formula 3, and Chemical Formula 4, each M can independently be any one selected from the Group 5 metal elements niobium (Nb), tantalum (Ta), and vanadium (V). According to yet another feature of the present invention, the Group 5 metal precursor compound can be a liquid at room temperature. A precursor composition for depositing a thin film containing a Group 5 metal according to an embodiment of the present invention includes a Group 5 metal precursor compound represented by Chemical Formula 1. A method for forming a thin film containing a Group 5 metal according to an embodiment of the present invention provides a method for forming a thin film containing a Group 5 metal, uses a Group 5 metal precursor compound represented by Chemical Formula 1, and deposits a thin film on a substrate by a Metal Organic Chemical Vapor Deposition (MOCVD) process or an Atomic Layer Deposition (ALD) process. According to another feature of the present invention, the deposition process can be performed in a temperature range of 50 to 700 °C. According to yet another feature of the present invention, the deposition process may include the following steps: transferring the Group 5 metal precursor compound to the substrate by a method selected from the bubbling method, the vapor phase Mass Flow Controller (MFC) method, the Direct Gas Injection (DGI) method, the Direct Liquid Injection (DLI) method, and the organic solution supply method of dissolving the Group 5 metal precursor compound in an organic solvent and transferring it. According to yet another feature of the present invention, the Group 5 metal precursor compound can be transferred to the substrate together with a carrier gas by the bubbling method or the direct gas injection method, and the carrier gas may include one or more selected from argon (Ar), nitrogen (N 2 ), helium (He), and hydrogen (H 2 ). According to yet another feature of the present invention, the deposition process may include the following steps: when forming a thin film containing a Group 5 metal, supplying a reaction gas selected from one or more of water vapor (H 2 O), oxygen (O 2 ), ozone (O 3 ), and hydrogen peroxide (H 2 O 2 ). According to yet another feature of the present invention, the deposition process may include the following steps: when forming a thin film containing a Group 5 metal, supplying a reaction gas selected from one or more of ammonia (NH 3 ), hydrazine (N 2 H 4 ), nitrous oxide (N 2 O), and nitrogen (N 2 ). The present invention has been described in detail above by way of examples. However, the present invention is not necessarily limited to these examples, and various modifications can be made without departing from the technical idea of the present invention. Therefore, the examples disclosed in the present invention are not for limiting the technical idea of the present invention, but for description, and the scope of the technical idea of the present invention is not limited by these examples. Therefore, it should be understood that the above-described examples are exemplary in all respects and not restrictive. The protection scope of the present invention should be interpreted according to the following claims, and all technical ideas within the same scope should be interpreted as being included in the patent application scope of the present invention. [Fig. 1] is a graph showing the growth rate of a thin film according to the deposition temperature when an atomic layer deposition process is performed using niobium precursor compounds according to Example 1 and Comparative Example 1, respectively. [Fig. 2] is a photograph showing the thermal stability of each sample according to Example 1 and Comparative Example 1. [Fig. 3] is a graph showing the results of thermogravimetric analysis (TGA) of the niobium precursor compound according to Example 1. [Fig. 4] is a graph showing the results of thermogravimetric analysis (TGA) of the niobium precursor compound according to Comparative Example 1. [Fig. 5] is a graph showing the results of thermogravimetric analysis (TGA) of the niobium precursor compound according to Comparative Example 2. [Fig. 6] is a graph showing the results of thermogravimetric analysis (TGA) of the niobium precursor compound according to Comparative Example 3. [Fig. 7] is a graph showing the results of thermogravimetric analysis (TGA) of the tantalum precursor compound according to Example 4. [Fig. 8] is a graph showing the growth rate of a thin film according to the deposition temperature when an atomic layer deposition process is performed using the tantalum precursor compound according to Example 4.

Claims

1. A Group 5 metal precursor compound, said Group 5 metal precursor compound being selected from compounds represented by the following chemical formulas 2, 3, and 4. [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] In said chemical formulas 2, 3, and 4, M is each independently selected from any one of the Group 5 metal elements niobium (Nb), tantalum (Ta), and vanadium (V).

2. The Group 5 metal precursor compound as claimed in claim 1, wherein the Group 5 metal precursor compound is a liquid at room temperature.

3. A precursor composition for depositing a thin film containing a Group 5 metal, comprising a Group 5 metal precursor compound as claimed in any one of claims 1 to 2.

4. A method for forming a thin film containing a Group 5 metal, wherein a thin film is deposited on a substrate using a Group 5 metal precursor compound as described in any one of claims 1 to 2 by means of a metal-organic chemical vapor deposition (MOCVD) process or an atomic layer deposition (ALD) process.

5. The method for forming a thin film containing a Group 5 metal as described in claim 4, wherein the deposition process is performed in a temperature range of 50 to 700°C.

6. The method for forming a thin film containing a Group 5 metal as described in claim 4, wherein the deposition process includes the step of transferring the Group 5 metal precursor compound to the substrate by means of one of the following methods: bubbling, vapor phase mass flow controller (MFC), direct gas injection (DGI), direct liquid injection (DLI), or an organic solution supply method that dissolves and transfers the Group 5 metal precursor compound in an organic solvent.

7. The method for forming a thin film containing a Group 5 metal as described in claim 6, wherein the Group 5 metal precursor compound can be transferred onto the substrate together with a carrier gas by the bubbling method or the direct gas injection method, and the carrier gas can include one or more selected from argon (Ar), nitrogen (N2), helium (He) and hydrogen (H2).

8. The method for forming a thin film containing a Group 5 metal as claimed in claim 4, the deposition process comprising the step of supplying one or more reaction gases selected from water vapor (H2O), oxygen (O2), ozone (O3) and hydrogen peroxide (H2O2) when forming the thin film containing the Group 5 metal.

9. The method for forming a thin film containing a Group 5 metal as described in claim 4, the deposition process comprising the step of supplying one or more reaction gases selected from ammonia (NH3), hydrazine (N2H4), nitrous oxide (N2O), and nitrogen (N2) during the formation of the thin film containing the Group 5 metal.

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