Precursor for forming fulvene-based thin film

Abstract

With a specific fulvene-based structure, the precursor for forming a thin film according to the present invention exhibits excellent reactivity during a manufacturing process, enables mass production at high yield, and provides high purity. In addition, deposition efficiency is excellent in a thin film manufacturing process, a thin film can be formed in a wider temperature range, and a high-quality thin film having excellent thermal stability can be manufactured even in such a wide temperature range. Furthermore, there is an effect of manufacturing a thin film having excellent various characteristics such as work function characteristics, deposition rate characteristics, thickness uniformity characteristics, step coverage characteristics, etc.

Description

fulben-based thin film forming precursor

[0001] The present invention relates to a fulven-based thin film forming precursor, and more specifically, to a thin film forming precursor used for manufacturing a thin film.

[0002] With the development of the modern electronics industry, thin film technology plays a pivotal role in various advanced technology fields, such as semiconductors, displays, and solar cells. For example, various electronic devices require electronic components used in CPUs (Central Processing Units), GPUs (Graphics Processing Units), DRAMs (Dynamic Random Access Memory), and capacitors.

[0003] These electronic devices are manufactured using thin film formation methods such as Atomic Layer Deposition (ALD) and Chemical Vapor Deposition (CVD), utilizing thin film precursors as raw material sources. Specifically, advanced deposition technologies like CVD and ALD are primarily used to form thin films, and in this process, the need for high-purity and high-efficiency thin film precursors is increasing. As such, thin film technology utilizing precursors enables improved device performance and miniaturization, and has established itself as an essential element in applications requiring high resolution, high efficiency, and high reliability.

[0004] Such precursors for thin film formation must be highly reactive and capable of accurately realizing the desired thin film composition, while simultaneously possessing excellent thermal stability and vaporization characteristics.

[0005] In particular, metal-organic ligand-based precursors for thin film formation are widely used because they are suitable for effectively incorporating specific metal elements into the film. Among these, fulbene-based ligand compounds exhibit stable bonding with metals due to their unique structures and properties, and can provide excellent reactivity and deposition characteristics in thin film formation processes. However, existing fulbene-based compounds have limitations, such as being complex or having limited reactivity, and require improvement in deposition efficiency and film quality.

[0006] Therefore, the development of new thin film precursors suitable for thin film formation processes, particularly fulbenzene compounds that provide improved physical and chemical properties, is crucial for strengthening competitiveness in the fields of electronic devices and high-tech.

[0007] [Prior Art Literature]

[0008] [Patent Literature]

[0009] Korean Registered Patent Publication No. 10-1434696 (August 20, 2014)

[0010]

[0011] The objective of the present invention is to provide a metal-organic ligand-based thin film forming precursor, which, when manufactured, exhibits excellent reactivity, enables mass production with high yield, and provides a high-purity thin film forming precursor.

[0012] Another objective of the present invention is to provide a thin film forming precursor for forming thin films that has excellent deposition efficiency and thin film quality.

[0013] Another objective of the present invention is to provide a thin film forming precursor that enables thin film formation over a wider temperature range and exhibits excellent thermal stability over a wide temperature range.

[0014] Another objective of the present invention is to provide a thin film forming precursor capable of producing a thin film with excellent various properties, such as work function characteristics, deposition rate characteristics, thickness uniformity characteristics, and step coverage characteristics.

[0015] The thin film forming precursor according to the present invention is represented by the following chemical formula 1.

[0016] [Chemical Formula 1]

[0017]

[0018] In the above Chemical Formula 1, M is a central metal; R1 and R2 are independently hydrogen or substituted or unsubstituted linear or branched alkyls, R3 and R4 are hydrogen or independently substituted or unsubstituted linear or branched alkyls, wherein at least one is a substituted or unsubstituted linear or branched alkyl, and R5 to R 10 is a substituted or unsubstituted linear or branched alkyl.

[0019] In the thin film forming precursor according to one example of the present invention, R1 and R2 in Chemical Formula 1 may be hydrogen.

[0020] The thin film forming precursor according to the present invention has the effect of having excellent reactivity when manufacturing a thin film forming precursor, enabling mass production with high yield, and possessing high purity.

[0021] In addition, the thin film forming precursor according to the present invention has the effect of excellent deposition efficiency and thin film quality when manufacturing a thin film.

[0022] In addition, the thin film forming precursor according to the present invention enables thin film formation over a wider temperature range and has the effect of producing a thin film with excellent thermal stability even over a wide temperature range.

[0023] In addition, the thin film forming precursor according to the present invention has the effect of being able to produce a thin film with excellent various characteristics, such as work function characteristics, deposition rate characteristics, thickness uniformity characteristics, and step coverage characteristics.

[0024] The embodiments and specific composition ratios of the present invention are merely illustrative to aid understanding and are not intended to limit or restrict the technical scope of the invention. The types, contents, manufacturing conditions, numerical ranges, etc., of the components described in the specification are merely examples, and those skilled in the art may change, add, or substitute components according to the desired physical properties or fields of application. Such variations, modifications, and equivalent substitutions should also be understood as naturally being included within the scope of the present invention, provided they do not deviate from the essence of the invention.

[0025] As used in this specification, "comprising" is an open description equivalent to expressions such as "comprising," "containing," "having," and "characteristics," and does not exclude elements, materials, or processes not additionally listed.

[0026] In this specification, the unit '%' used without special mention means 'weight%' unless otherwise defined.

[0027] The term "independent" as used herein, when used in the context describing an R group indicated in a chemical formula, may be selected independently of other R groups having the same or different subscripts or superscripts, as well as independently of any additional species of the same R group. Furthermore, unless otherwise specifically stated, it should be understood that the values ​​of R groups are independent of each other when used in different chemical formulas.

[0028] All compounds or substituents mentioned in this specification may be substituted or unsubstituted unless otherwise specifically noted. Herein, "substituted" means that hydrogen is replaced by any one selected from the group consisting of a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an amino group, a thio group, a methylthio group, an alkoxy group, a nitrile group, an aldehyde group, an epoxy group, an ether group, an ester group, a carbonyl group, an acetal group, a ketone group, an alkyl group, a perfluoroalkyl group, a cycloalkyl group, a heterocycloalkyl group, an allyl group, a benzyl group, an aryl group, a heteroaryl group, derivatives thereof, and combinations thereof.

[0029]

[0030] The fulvene-based thin film forming precursor according to the present invention is an organometallic complex in which a fulvene-based ligand compound having a specific structure described below is bonded to a central metal. Since the fulvene-based ligand having a resonance structure is stably bonded to the central metal, the thermal stability and reaction stability are significantly improved, allowing for the stable formation of a thin film even over a wide temperature range as described above, and enabling the stable production of high-quality thin films due to excellent thermal stability. Furthermore, it has the effect of reducing the generation of by-products during the process and enables the production of thin films with excellent various characteristics such as work function characteristics, deposition rate characteristics, thickness uniformity characteristics, step coverage characteristics, and purity characteristics.

[0031] Specifically, the thin film forming precursor according to the present invention can stably form a thin film along with the aforementioned thermal stability by forming a conjugation structure by a fulben-based organic ligand as shown in the figure below.

[0032]

[0033] In addition, it has the effect of providing a high-purity thin film forming precursor that exhibits excellent reactivity during the manufacturing process and enables mass production with high yield.

[0034] The thin film forming precursor according to the present invention is represented by the following chemical formula 1.

[0035] [Chemical Formula 1]

[0036]

[0037] In the above chemical formula 1, R1 and R2 are independently hydrogen or substituted or unsubstituted linear or branched alkyls. Here, the alkyl may be an alkyl (C1-C10), preferably an alkyl (C1-C5), more preferably an alkyl (C1-C3), and even more preferably an alkyl (C1-C2).

[0038] As a preferred example, in the above chemical formula 1, both R1 and R2 may be hydrogen. If this is satisfied, the above effect may be further enhanced.

[0039] In the above chemical formula 1, R3 and R4 are hydrogen or are linear or branched alkyls that are independently substituted or unsubstituted, wherein at least one of R3 and R4 is a linear or branched alkyl that is substituted or unsubstituted. Here, the alkyl may be an alkyl (C1-C10), preferably an alkyl (C1-C5), more preferably an alkyl (C1-C3), and even more preferably an alkyl (C1-C2). Thus, when at least one of R3 and R4 is a linear or branched alkyl that is substituted or unsubstituted, the aforementioned effect can be achieved.

[0040] Preferably, the thin film forming precursor may be represented by one of the compounds of Formula 2 below. As in Formula 2 below, if both R1 and R2 are hydrogen and at the same time R3 and R4 are each hydrogen and alkyl, or if both are alkyl (especially methyl), the above effect can be greatly enhanced.

[0041] [Chemical Formula 2]

[0042]

[0043] In one example of the present invention, in Formula 1, at least one of R1 and R2 may be a substituted or unsubstituted linear or branched alkyl. Here, the alkyl may be an alkyl (C1-C10), preferably an alkyl (C1-C5), more preferably an alkyl (C1-C3), and even more preferably an alkyl (C1-C2). An example of the thin film forming precursor may be a compound represented by one of the compounds of Formula 3 below.

[0044] [Chemical Formula 3]

[0045]

[0046] As a preferred example, in the above formula 1, both R1 and R2 may be substituted or unsubstituted linear or branched alkyls. Here, the alkyl may be an alkyl (C1-C10), preferably an alkyl (C1-C5), more preferably an alkyl (C1-C3), and even more preferably an alkyl (C1-C2). If this is satisfied, the above effect may be further enhanced.

[0047] Preferably, the thin film forming precursor may be represented by one of the compounds of Formula 4 below. As in Formula 4 below, if both R1 and R2 are substituted or unsubstituted linear or branched alkyls, and at the same time R3 and R4 are each hydrogen and alkyl, or both are alkyl (especially methyl), the above effect may be greatly enhanced.

[0048] [Chemical Formula 4]

[0049]

[0050] A thin film forming precursor according to a preferred example may be represented by one of the compounds of Chemical Formula 5 below. If this is satisfied, the above effect may be further enhanced.

[0051] [Chemical Formula 5]

[0052]

[0053] A thin film forming precursor according to a preferred embodiment may be represented by one of the compounds of Chemical Formula 6 below. If this is satisfied, the above effect can be maximized, and process efficiency and cost efficiency can be significantly improved.

[0054] [Chemical Formula 6]

[0055]

[0056] In the above chemical formulas 1 to 5, R5 to R 10 is a substituted or unsubstituted linear or branched alkyl. Here, the alkyl may be an alkyl (C1-C10), preferably an alkyl (C1-C5), more preferably an alkyl (C1-C3), and even more preferably an alkyl (C1-C2).

[0057] In the above chemical formula 1, M is the central metal, and various types of metals that can be used for thin film formation may be used, for example, selected from titanium (Ti), zirconium (Zr), and hafnium (Hf). Accordingly, it is possible to manufacture a thin film containing the central metal as a main component. For example, when manufacturing a thin film using the thin film forming precursor according to the present invention, a thin film such as a nitride of the central metal, an oxide of the central metal, a carbide of the central metal, or a carbonitride of the central metal can be manufactured.

[0058] The thin film forming precursor according to the present invention may have a temperature at which the compound reaches 50 wt% during thermogravimetric analysis (TGA) of 265°C or higher, 270°C or higher, 285°C or higher, or 290°C or higher. In this case, the upper limit is not strictly restricted and may be, for example, 330°C. Thermogravimetric analysis analyzes the mass of a sample with respect to time or temperature (heat) while the sample's temperature changes in a specific atmosphere, and serves as a measure of thermal stability by measuring the weight of the compound at that temperature. For example, the temperature at which the compound reaches 50 wt% during thermogravimetric analysis refers to the temperature at which the weight of the compound becomes 50% when heat is applied to the compound, causing it to decompose and lose weight. Specific test conditions may follow KS M ISO 11358-1.

[0059] The thin film forming precursor according to the present invention can be manufactured into a thin film through various thin film forming methods, and for example, various thin film forming methods such as atomic layer deposition and chemical vapor deposition can be used.

[0060] Specifically, a preferred thin film forming method according to the present invention may include a) a step of positioning a substrate in a reactor and b) a step of supplying the thin film forming precursor and a reactive gas into the reactor and reacting them to form a thin film on the substrate.

[0061] In step a) above, the temperature of the substrate may be maintained at a level sufficient to form a thin film in subsequent steps, for example, 100 to 1,000°C, specifically 200 to 500°C, more specifically 250 to 400°C.

[0062] In step b) above, a thin film forming precursor is adsorbed onto a substrate to form a thin film, and various substrates capable of forming a thin film can be used, for example, it may be preferable to use one for semiconductor manufacturing. As a specific example, a silicon substrate (Si), a silica substrate (SiO2), a silicon nitride substrate (SiN), a silicon oxynitride substrate (SiON), a titanium nitride substrate (TiN), a tantalum nitride substrate (TaN), a tungsten substrate (W), or a precious metal substrate, for example, a platinum substrate (Pt), a palladium substrate (Pd), a rhodium substrate (Rh), or a gold substrate (Au) may be used.

[0063] Step b) above can be described in more detail as being divided into three stages: supplying a thin film forming precursor, supplying a reaction gas, and the reaction thereof. Specifically, step b) may include b1) a step of supplying the thin film forming precursor into the reactor, b2) a step of supplying the reactive gas into the reactor, and b3) a step of forming a thin film on the substrate by the reaction of the thin film forming precursor and the reactive gas.

[0064] In step b1) above, the supply of the thin film formation precursor can be performed through various methods, for example, a vapor pressure-based volatile transport method, a direct liquid injection method, or a liquid delivery system (LDS). Through such supply methods, excellent process efficiency and high-quality thin films can be formed.

[0065] When the thin film forming precursor is supplied in step b), specifically in step b1), the thin film forming precursor may be supplied in the form of a composition containing other components such as a diluent and an additive together with the thin film forming precursor. In detail, step b), specifically b1), may be a step of supplying a precursor composition containing the thin film forming precursor into the reactor. In this way, process / physical property parameters such as the deposition rate, reaction rate, and the thickness of the thin film formed can be controlled.

[0066] The thin film forming precursor supplied in step b1) and the reactive gas supplied in step b2) can be maintained and stored at a temperature of 50 to 250°C, specifically 100 to 200°C, until supplied to the substrate in the reactor. Therefore, adverse effects caused by rapid temperature changes can be minimized as the thin film forming precursor and the reactive gas are supplied into the reactor.

[0067] In step b2) above, the reactive gas is not significantly limited as long as it reacts with the thin film forming precursor to form a thin film or reacts with the layer formed by the thin film forming precursor to affect the composition or composition ratio of the layer, and various types may be used depending on the purpose. As a specific example, the reactive gas may include one or more oxidizing gases selected from water vapor, oxygen, ozone, and hydrogen peroxide; one or more nitrogen-based gases selected from ammonia, nitric oxide, nitrous oxide, nitrogen dioxide, triasein, hydrazine, methylhydrazine, dimethylhydrazine, and tert-butylhydrazine; silicon-based gases such as silane; and reducing gases such as hydrogen; and one or more selected from the like. The reactive gas may be supplied to the thin film forming precursor in a gaseous state or in a plasma state. As a specific example, various plasmas may be used, such as inductively coupled plasma (ICP), RF plasma, DC plasma, or remote plasma.

[0068] The thin film formed in step b3) above may have various compositions depending on the type of reactive gas, and examples include metal nitrides, metal oxides, metal carbides, or metal carbonitrides as described above. Specifically, when an oxidizing gas such as water vapor, oxygen, or ozone is used, a metal oxide thin film may be formed, and when a reducing gas such as hydrogen, ammonia, hydrazine, or silane is used as the reactive gas, a composite metal or metal nitride thin film may be formed.

[0069] A thin film forming method according to one example of the present invention may further include a purging step, wherein the purging step may be performed between step b1) and step b2), or after step b3). The purging step may supply an inert gas into the reactor to help the thin film forming precursor move to the substrate or to form an appropriate pressure to facilitate the deposition of the thin film on the substrate. Additionally, impurities or byproducts present in the reactor may be released to the outside to form a high-purity thin film. At this time, the pressure inside the reactor may be 1 to 5 torr, but is not limited thereto. Furthermore, the inert gas may be any substance that does not react with the thin film forming precursor and the reaction gas, and may include one or more selected from, for example, argon (Ar), nitrogen (N2), and helium (He).

[0070] If the thin film forming precursor and the reactive gas are supplied separately in step b) to form a thin film, that is, if steps b1) and b2) are performed sequentially, it may be an atomic layer deposition method. Additionally, if steps b1) and b2) are performed simultaneously to form a thin film, it may be a chemical vapor deposition method.

[0071] When steps b1) and b2) are performed sequentially, that is, when the thin film forming precursor and the reactive gas are supplied sequentially, self-limited growth behavior of the thin film can be achieved, in which the growth rate is determined by the number of reaction sites on the surface of the initial substrate. At this time, it goes without saying that there is no restriction on the order of steps b1) and b2). The process including steps b1) and b2) can be repeated as one cycle, and atomic layer deposition can be performed through the aforementioned self-limited growth. In the atomic layer deposition method, atomic layers are formed by chemical adsorption reactions of surface functional groups of a first material and a second material, and atomic layers are chemically adsorbed alternately by the two different materials. Specifically, a series of processes consisting of the adsorption process of the thin film forming precursor, the adsorption process of the purge and reactive gas, and the purge process can constitute one cycle, and the thickness of the thin film can be controlled at the atomic layer level by adjusting the number of these cycles. In addition to this, chemical vapor deposition in which steps b1) and b2) are performed simultaneously is also possible.

[0072] When the above steps b1) and b2) are performed simultaneously, that is, when the thin film forming precursor and the reactive gas are supplied into the reactor at the same time, reactions in the gas phase may occur in addition to reactions on the substrate surface, and this may affect the film quality of the thin film.

[0073] In this way, the thickness of the thin film can be increased by repeatedly performing the process including step b), specifically steps b1) to b3), as one cycle. Accordingly, a thin film forming method according to an example of the present invention may further include a step of repeatedly performing step b).

[0074] The reaction temperature in step b) above, specifically the reaction temperature in step b3), may be sufficient as long as the thin film forming precursor reacts to form a thin film, but for example, it may be 100 to 1,000°C, specifically 200 to 500°C, preferably 250 to 400°C, and more preferably 250 to 370°C. If this is satisfied, a metal thin film having the desired physical state and composition can be manufactured at a sufficient growth rate. In particular, since the aforementioned thin film forming precursor has very high thermal stability, it is possible to deposit at higher temperatures and deposit a thin film with a lower impurity content. Preferably, when performed in the range of 250 to 370°C, not only can contamination by impurities such as oxygen and silicon be minimized, but thickness control is also easy as the deposition rate according to temperature is relatively constant within the temperature range.

[0075] A thin film formation method according to an example of the present invention may further include one or more post-processing steps selected from heat treatment, plasma treatment, and light irradiation after step b). In this case, the post-processing step may be used to supply energy for the deposition of the thin film formation precursor and may be performed in the presence of the aforementioned reactive gas. In particular, when the thin film formation precursor according to the present invention is deposited adjacent to a thin film of a different composition, such as an insulating film such as a dielectric layer, the mutual reactivity is significantly reduced, resulting in excellent chemical stability and preventing the formation of an interlayer due to low reactivity and the resulting degradation of electrical performance.

[0076]

[0077] The present invention will be described in detail below through examples, but these are intended to explain the invention in more detail and the scope of the present invention is not limited by the following examples.

[0078]

[0079] Preparation of ligand compounds for manufacturing thin film-forming precursors

[0080]

[0081] [Preparation Example 1]

[0082] The compound of the following chemical formula 6-a was prepared by the following method.

[0083] 200 g of cyclopentadiene was dissolved in a solution containing 196 g of methyl ethyl ketone and 1,320 ml of methanol in a completely dry 3-neck round flask while purging with N2, and the temperature of the reaction mixture was maintained below -10 °C. Then, 226 g of pyrrolidine was added dropwise, and the yellow reaction mixture was heated to room temperature for 1 hour, after which 200 g of acetic acid was slowly added. After 10 minutes, the reaction mixture was poured into 5 L of cold water and extracted twice with diethyl ether. The combined organic layer was dried with anhydrous magnesium sulfate and all volatile substances were removed under reduced pressure to obtain 296 g of yellow methyl ethyl fulben of the following chemical formula 6-a.

[0084]

[0085] [Chemical Formula 6-a]

[0086]

[0087]

[0088] [Preparation Example 2]

[0089] The compound of the following chemical formula 6-b was prepared by the following method.

[0090] 150 g of cyclopentadiene was dissolved in a solution containing 205 g of methylisopropylketone and 1,000 ml of methanol in a completely dry 3-neck round flask while purging with N2, and the temperature of the reaction mixture was maintained below -10 °C. Then, 170 g of pyrrolidine was added dropwise, and the yellow reaction mixture was heated to room temperature for 1 hour, after which 150 g of acetic acid was slowly added. After 10 minutes, the reaction mixture was poured into 5 L of cold water and extracted twice with diethyl ether. The combined organic layer was dried with anhydrous magnesium sulfate and all volatile substances were removed under reduced pressure to obtain 230 g of dark yellow methylisopropylfulben of the following chemical formula 6-b.

[0091]

[0092] [Chemical Formula 6-b]

[0093]

[0094]

[0095] [Preparation Example 3]

[0096] The compound of the following chemical formula 6-c was prepared by the following method.

[0097] 150 g of cyclopentadiene was dissolved in a solution containing 233 g of diisopropylketone and 1,000 ml of methanol in a completely dry 3-neck round flask while purging with N2, and the temperature of the reaction mixture was maintained below -10 °C. Then, 170 g of pyrrolidine was added dropwise, and the yellow reaction mixture was heated to room temperature for 1 hour, after which 150 g of acetic acid was slowly added. After 10 minutes, the reaction mixture was poured into 5 L of cold water and extracted twice with diethyl ether. The combined organic layer was dried with anhydrous magnesium sulfate and all volatile substances were removed under reduced pressure to obtain 272 g of dark yellow diisopropylfulben of the following chemical formula 6-c.

[0098]

[0099] [Chemical Formula 6-c]

[0100]

[0101]

[0102] <Preparation of Thin Film Forming Precursor>

[0103]

[0104] [Example 1]

[0105] One equivalent of tetrakis(dimethylamino)zirconium (Zr(N(CH3)2)4) was placed in a flask connected to a Schlenk line, and 35 equivalents of n-hexane were added. Then, while maintaining the temperature at -30°C, 1.2 equivalents of the ligand compound of Preparation Example 1 (Chemical Formula 6-a) were added to the n-hexane. Subsequently, the temperature was slowly raised to room temperature, then to the reflux temperature, and stirred for more than 18 hours. Then, the reaction solution was subjected to reduced pressure to remove the solvent, and the solution was distilled to obtain a thin film forming precursor.

[0106]

[0107] [Example 2]

[0108] A thin film forming precursor was obtained in the same manner as in Example 1, except that the ligand compound of Preparation Example 2 (Chemical Formula 6-b) was used instead of the ligand compound of Preparation Example 1 (Chemical Formula 6-a) in Example 1.

[0109]

[0110] [Example 3]

[0111] A thin film forming precursor was obtained in the same manner as in Example 1, except that the ligand compound of Preparation Example 3 (Chemical Formula 6-c) was used instead of the ligand compound of Preparation Example 1 (Chemical Formula 6-a) in Example 1.

[0112]

[0113] [Comparative Example 1]

[0114] A thin film forming precursor was obtained in the same manner as in Example 1, except that Fulvene was used instead of the ligand compound (Formula 6-a) of Preparation Example 1 in Example 1.

[0115]

[0116] [Comparative Example 2]

[0117] A thin film forming precursor was obtained in the same manner as in Example 1, except that cyclopentadiene was used instead of the ligand compound (Formula 6-a) of Preparation Example 1 in Example 1.

[0118]

[0119] Thin film manufacturing

[0120]

[0121] [Example 4]

[0122] A zirconium oxide (ZrO2) thin film was prepared by atomic layer deposition using the thin film forming precursor prepared in Example 1 and ozone gas as the reaction gas in the following manner.

[0123] Specifically, the thin film forming precursor was placed in a canister and heated to 80°C. Then, argon was flowed through it at a flow rate of 700 sccm, and the thin film forming precursor, which had vaporized into a vapor phase in the canister, was introduced into the deposition chamber for 3 seconds. Subsequently, argon purging was performed by supplying argon gas at 500 sccm for 10 seconds. At this time, the pressure inside the deposition chamber was controlled to 1.5 Torr. Next, ozone was introduced into the deposition chamber as a reactive gas for 5 seconds, followed by argon purging for 10 seconds. At this time, a substrate made of SiO2 was used as the substrate on which the thin film would be formed, and the temperature of the substrate was controlled to 250°C. This process was repeated 100 times to produce a zirconium oxide thin film.

[0124]

[0125] [Example 5]

[0126] A thin film was prepared in the same manner as in Example 4, except that Example 2 was used instead of Example 1 as the thin film forming precursor in Example 4.

[0127]

[0128] [Example 6]

[0129] A thin film was prepared in the same manner as in Example 4, except that Example 3 was used instead of Example 1 as the thin film forming precursor in Example 4.

[0130]

[0131] [Experimental Example 1] NMR spectrum of thin film forming precursor

[0132] The thin film forming precursors prepared in Examples 1 to 3 were analyzed using the Nuclear Magnetic Resonance (NMR) method, and the results are shown in Figure 1.

[0133]

[0134] [Experimental Example 2] Evaluation of Thermal Stability of Thin Film Forming Precursor

[0135] The thermal stability of the thin film forming precursors prepared in Examples 1 to 3 and Comparative Example 1 and Comparative Example 2 was evaluated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Specifically, thermogravimetric analysis and differential scanning calorimetry were performed by increasing the temperature of the thin film forming precursor from an initial temperature of 30°C to 500°C at a heating rate of 10°C / min while injecting argon gas at a pressure change rate of 1.5 bar / min. For other specific test conditions, refer to KS M ISO 11358-1.

[0136]

[0137] [Experimental Example 3] Evaluation of Thin Film Work Function

[0138] The work function of the thin films prepared in Examples 4 to 6 was measured by adjusting the number of cycles so that the work function was measured at the point when the thickness reached 3.5 nm. At this time, the work function was measured through Kelvin probe analysis.

[0139]

[0140] [Experimental Example 4] Evaluation of Impurities and Purity During Thin Film Fabrication

[0141] Auger Electron Spectroscopy (AES) analysis was performed to compare the impurity reduction characteristics, i.e., process byproduct reduction characteristics and purity, during thin film fabrication in Examples 4 to 6.

[0142]

[0143] [Experimental Example 5] Evaluation of Thin Film Deposition Rate

[0144] The thin film deposition rate according to the process temperature of the thin films prepared in Examples 4 to 6 was evaluated. The deposition rate was measured as the thickness (Å) of the thin film formed per cycle.

[0145]

[0146] [Experimental Example 6] Evaluation of Thin Film Thickness Uniformity

[0147] The thickness uniformity of the thin films prepared in Examples 4 to 6 was evaluated using a transmission electron microscope (TEM).

[0148]

[0149] [Experimental Example 7] Evaluation of Thin Film Step Coverage

[0150] The step coverage of the thin films prepared in Examples 4 to 6 was evaluated using a transmission electron microscope.

[0151]

[0152] Ligand Compound Preliminary Comparative Example 12312 Chemical Formula 6-a Chemical formula 6-b Chemical formula 6-c OFulvene OCyclopentadiene O

[0153]

[0154] As a result, it was confirmed that the thin film forming precursors prepared in Examples 1, 2, and 3 had superior thermal stability characteristics compared to Comparative Examples 1 and 2.

[0155] In addition, it was confirmed that the thin films prepared in Examples 4, 5, and 6 exhibited excellent characteristics among at least one of the work function, impurity, deposition rate, thickness uniformity, and step coverage characteristics.

Claims

1. A thin film forming precursor represented by the following chemical formula 1: [Chemical Formula 1] (In the above chemical formula 1, M is the central metal; R1 and R2 are independently hydrogen or substituted or unsubstituted linear or branched alkyls; R3 and R4 are hydrogen or linear or branched alkyls that are independently substituted or unsubstituted from each other, wherein at least one is a substituted or unsubstituted linear or branched alkyl; R5 to R 10 is a substituted or unsubstituted linear or branched alkyl.

2. In Paragraph 1, A thin film forming precursor, wherein R1 and R2 in Chemical Formula 1 above are hydrogen.

3. In Paragraph 2, A thin film forming precursor represented by one of the compounds of Chemical Formula 2 below: [Chemical Formula 2] (In the above chemical formula 2, M is the central metal, and R5 to R 10 is a substituted or unsubstituted linear or branched alkyl).

4. In Paragraph 1, A thin film forming precursor in the above chemical formula 1, wherein at least one of R1 and R2 is a substituted or unsubstituted linear or branched alkyl.

5. In Paragraph 4, A thin film forming precursor represented by one of the compounds of Chemical Formula 4 below: [Chemical Formula 4] (In the above chemical formula 4, M is the central metal, and R5 to R 10 is a substituted or unsubstituted linear or branched alkyl).

6. In Paragraph 1, A thin film forming precursor represented by one of the compounds of Chemical Formula 5 below: [Chemical Formula 5] (In the above chemical formula 5, M is the central metal, and R5 to R 10 is a substituted or unsubstituted linear or branched alkyl).

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