Method of manufacturing a ruthenium-containing thin film

Abstract

A method for manufacturing a ruthenium-containing thin film includes: supplying a transport gas and a ruthenium precursor represented by chemical formula 1 to a chamber on which a substrate is mounted, and depositing a ruthenium-containing thin film on the substrate while injecting a reducing reaction gas into the chamber; and a post-processing process including at least one of heat treatment in a reducing reaction gas atmosphere and plasma treatment in a reducing reaction gas atmosphere, wherein the reducing reaction gas is selected from at least one of H2, hydrazine (NH2NH2), NH3 and BH3.

Description

Method for manufacturing ruthenium-containing thin film The present disclosure relates to a method for manufacturing a ruthenium-containing thin film, and more particularly to a method for manufacturing a ruthenium-containing thin film including post-treatment, the post-treatment including at least one of depositing a ruthenium-containing thin film using a ruthenium precursor having a specific structure and a reducing reaction gas, performing heat treatment in a reducing reaction gas atmosphere, and performing plasma treatment in a reducing reaction gas atmosphere. [Cross-reference to related applications] This application claims the priority and benefits of Korean Patent Application No. 10-2023-0035752, filed with the Korean Intellectual Property Office on March 20, 2023, the entire contents of which are incorporated herein by reference. A ruthenium (Ru) thin film can be used as a seed layer or an electrode (e.g., a gate of a transistor or a capacitor) in a wiring structure of a semiconductor device. As semiconductor devices are highly integrated and their size is reduced, the ruthenium (Ru) thin film used in semiconductor devices also requires improved uniformity and coating properties. On the other hand, as methods for depositing thin films in semiconductor devices, molecular beam epitaxy (MBE), chemical vapor deposition (CVD), physical vapor deposition (PVD), etc. are being studied. Recently, as the size of semiconductor devices has been reduced (which has in turn led to a reduction in design rules), atomic layer deposition (ALD) based on a self-limiting surface reaction mechanism has been widely studied as a deposition method that satisfies low-temperature processes, precise thickness control, and the uniformity and coating properties of thin films. The atomic layer deposition (ALD) method for forming a ruthenium thin film has conventionally used Ru(OD) 3 [ruthenium(III) tris(2,4-octanedionato)]、Ru(EtCP) 2 [bis(ethylcyclopentadienyl)ruthenium(II)] etc. as ruthenium raw materials. However, Ru(OD) among these 3 contains oxygen, making it difficult to deposit pure ruthenium on the reaction substrate, and moreover having the problem of forming RuO on a part of the substrate x . In addition, Ru(EtCP) 2is a cyclopentadiene-based compound, making it difficult for ruthenium atoms to break chemical bonds and exist independently, thereby causing problems of leaving a large amount of impurities on the ruthenium thin film. Additionally, Ru(EtCP) 2 By using O 2 plasma, it is not easily decomposed and is thus deposited to form RuO 2 film. Therefore, the RuO 2 film needs to be reduced by using H 2 again to obtain the Ru film, which is another problem. Chemical vapor deposition is also being studied to develop a process for forming a ruthenium thin film. However, (cyclohexadiene)Ru(CO) used as a ruthenium raw material in the process 3 has a problem of decomposition during the deposition process due to significantly reduced thermal stability. Even materials with improved thermal stability in traditional technologies still have problems such as reduced volatility or deteriorated resistivity. Therefore, a method is needed to produce a high-purity ruthenium-containing thin film by reducing the impurity content while also improving the properties of the thin film (e.g., room-temperature thermal stability and resistivity). One aspect of the present disclosure provides a method for manufacturing a ruthenium-containing thin film with high purity to prevent decomposition under storage conditions and use conditions due to improved thermal stability of the ruthenium precursor and to increase the resistivity of the thin film by a post-treatment step. Embodiments of the present invention provide a method for manufacturing a ruthenium-containing thin film, the method comprising: supplying a carrier gas and a ruthenium precursor represented by Chemical Formula 1 to a chamber in which a substrate is installed, and depositing a ruthenium-containing thin film on the substrate when a reduction reaction gas is injected into the chamber; and a post-treatment process including performing at least one of heat treatment and plasma treatment in a reduction reaction gas atmosphere, wherein the reduction reaction gas is selected from at least one of H 2 , hydrazine (NH 2 NH 2 ), NH 3 and BH 3 . [Chemical Formula 1] In Chemical Formula 1, R is a substituted or unsubstituted C1 to C5 alkyl group. The temperature of the substrate can be maintained at 80°C to 300°C during the supply. The reducing reaction gas can be injected in an amount of 0.1 mol to 500 mol per 1 mol of the ruthenium precursor represented by Chemical Formula 1. The heat treatment can be carried out at a temperature of 200 °C to 1000 °C. The plasma treatment can be carried out at a radio frequency (RF) power of 50 W to 1000 W. The method for manufacturing the ruthenium-containing film may further include purging by supplying an inert gas. The specific resistance of the ruthenium-containing film can be less than or equal to 25 μΩ·cm. The ruthenium-containing film can have a carbon content of less than or equal to 2 atomic %. The ruthenium-containing film can have an oxygen content of less than or equal to 1 atomic %. The ruthenium-containing film can have a nitrogen content greater than 0 and less than 3 atomic %. The ruthenium-containing film can have a hydrogen content of less than or equal to 7 atomic %. According to an embodiment, using a ruthenium precursor having a specific structure improves the thermal stability, prevents decomposition under storage conditions and use conditions, improves the film resistivity through a post-treatment step, and provides a ruthenium-containing film with high purity. Hereinafter, the present disclosure will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the present invention are shown. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. To clearly illustrate the present disclosure, parts not related to the description will not be repeated throughout the specification, and the same reference numerals refer to the same or similar components. For better understanding and ease of explanation, the size and thickness of each component shown in the drawings are randomly indicated, and the present disclosure does not have to be limited to the shown size and thickness. In the drawings, for clarity, the thicknesses of layers, regions, etc. are enlarged. In the drawings, for ease of illustration, the thicknesses of some layers and regions are exaggerated. In addition, it should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, the element can be directly on the other element, or an intermediate element may also exist. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. In addition, being disposed "on" or "above" a reference part is disposed above or below the reference part and does not necessarily mean "on" or "above" in the relative direction towards gravity. In addition, unless explicitly stated to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply including the stated elements but not excluding any other elements. As used herein, unless otherwise defined, "substituted" means that at least one hydrogen of a compound is replaced by a substituent selected from the following: a halogen atom (F, Br, Cl, or I), a hydroxyl group, an alkoxy group, a nitro group, a cyano group, an amino group, an azide group, an amidino group, a hydrazino group, a hydrazono group, a carbonyl group, a carbamoyl group, a mercapto group, an ester group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof, a vinyl group, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C2-C20 alkynyl group, a C6-C30 aryl group, a C7-C30 arylalkyl group, a C6-C30 allyl group, a C1-C30 alkoxy group, a C1-C20 heteroalkyl group, a C3-C20 heteroarylalkyl group, a C3-C30 cycloalkyl group, a C3-C15 cycloalkenyl group, a C6-C15 cycloalkynyl group, a C3-C30 heterocycloalkyl group, and combinations thereof. As used herein, unless otherwise defined, "hetero" means independently containing 1 to 10 heteroatoms selected from N, O, S, and P. In addition, in this specification, an acrylic polymer means an acrylic polymer and a methacrylic polymer. Hereinafter, a method for manufacturing a ruthenium-containing film according to an embodiment will be described. The method for manufacturing a ruthenium-containing film according to an embodiment includes: supplying a transfer gas and a ruthenium precursor represented by Chemical Formula 1 to a chamber in which a substrate is installed, and depositing a ruthenium-containing film on the substrate when a reduction reaction gas is injected into the chamber; and a post-treatment process including at least one of heat treatment in a reduction reaction gas atmosphere and plasma treatment in a reduction reaction gas atmosphere, where the reduction reaction gas is selected from H 2 、hydrazine (NH 2 NH 2 ), NH 3 and BH 3 and at least one of them. [Chemical Formula 1] In Chemical Formula 1, R is a substituted or unsubstituted C1-C5 alkyl group. The present invention uses a ruthenium precursor represented by Chemical Formula 1 and uses a reduction reaction gas (for example, H 2 、hydrazine (NH 2 NH 2 ), NH 3 、BH 3or a mixture thereof), and further includes a post-treatment step of performing heat treatment and / or plasma treatment in a reducing reaction gas atmosphere, and thus improves the thermal stability by a process essentially including a ruthenium precursor having a specific structure and a post-treatment step, prevents the ruthenium precursor from decomposing under storage conditions and use conditions, and produces a high-purity ruthenium-containing film. Hereinafter, the method for manufacturing a ruthenium-containing film will be described with reference to FIG. 1 as compared with FIG. 2 showing the method for manufacturing a ruthenium-containing film according to Comparative Example 1. FIG. 1 is a schematic diagram illustrating a method for manufacturing a ruthenium-containing film according to an embodiment of the present invention, and FIG. 2 is a schematic diagram illustrating a method for manufacturing a ruthenium-containing film according to Comparative Example 1. Referring to FIG. 1, manufacturing a ruthenium-containing film may include: supplying a transfer gas and a ruthenium precursor represented by Chemical Formula 1 to a chamber in which a substrate is installed, and depositing a ruthenium-containing film (A) on the substrate when injecting a reducing reaction gas into the chamber; a post-treatment process including at least one of performing heat treatment in a reducing reaction gas atmosphere and performing plasma treatment in a reducing reaction gas atmosphere (B), and may further include purging (C) by supplying an inert gas. The method for manufacturing a ruthenium-containing film includes repeating the deposition step (A), the post-treatment step (B), and the purging step (C) as one cycle, and performing such a cycle (D) until a desired film thickness is obtained. In contrast, referring to FIG. 2, a ruthenium-containing film can be manufactured by the following steps: supplying a transfer gas and a ruthenium precursor represented by Chemical Formula 1 to a chamber in which a substrate is installed, depositing a ruthenium-containing film (A) on the substrate when injecting a reducing reaction gas into the chamber, and then purging (C) by additionally supplying an inert gas without performing a separate post-treatment step, and repeating such a cycle (D) as one cycle. If a post-treatment step is further included, the film resistivity can be increased and a ruthenium-containing film with high purity can be manufactured. At this time, the purging step (C) may be selectively included as needed. The deposition method can be atomic layer deposition (ALD), chemical vapor deposition (CVD), metalorganic chemical vapor deposition (MOCVD), low pressure chemical vapor deposition (LPCVD), plasma enhanced chemical vapor deposition (PECVD), or plasma enhanced atomic layer deposition (PEALD), and in terms of high purity and excellent physical properties, it is desirable to use atomic layer deposition (ALD) or chemical vapor deposition (CVD). In the method for manufacturing a ruthenium-containing film according to an embodiment of the present invention, a ruthenium precursor used as a precursor can be changed into a gaseous state by a method such as heating the film deposit and then introduced into the process chamber. In the method for manufacturing a ruthenium-containing film according to an embodiment of the present invention, a reducing reaction gas can be changed into a gaseous state by a method such as heating and then introduced into the process chamber in which a substrate adsorbed with a ruthenium precursor exists. In the method for manufacturing a ruthenium-containing film according to an embodiment of the present invention, the ruthenium precursor and the reducing reaction gas can be supplied to the chamber organically or independently of each other, and the ruthenium precursor and the reducing reaction gas can be supplied simultaneously or sequentially. In addition, the ruthenium precursor and the reducing reaction gas can be supplied to the chamber continuously or discontinuously, and the discontinuous supply can include a pulsed form. In an embodiment, the deposition method can be a chemical vapor deposition (CVD) method, in which case the supply of the ruthenium precursor and the injection of the reducing reaction gas can be carried out simultaneously. In the method for manufacturing a ruthenium-containing film according to an embodiment of the present invention, a purge step (C) can be carried out in at least one of before or after the post-treatment step. That is, the purge step can be carried out before or after the post-treatment step, or the purge step can be carried out before and after the post-treatment step respectively, and the purge step can be optionally carried out by supplying an inert gas into the chamber to discharge unreacted ruthenium precursor gas, by-product gas, or unreacted reducing reaction gas. The inert gas can be selected from nitrogen (N 2), any one or two or more of argon and helium. The injection amount of the purge gas is not limited, but specifically, it can be supplied in the range of 800 standard cubic centimeters per minute (sccm) to 5,000 standard cubic centimeters per minute, and more specifically, in the range of 1,000 standard cubic centimeters per minute to 3,000 standard cubic centimeters per minute. As long as the substrate according to the embodiment of the present invention is within the range recognized by those skilled in the art, the substrate can be used, and the temperature of the substrate is not limited either, but it can be maintained at 300 °C or lower in the chamber, preferably between 80 °C and 300 °C, and this temperature range is due to the decomposition characteristics of the ruthenium compound used as the precursor itself and the reaction characteristics with other substances (such as H 2 , hydrazine (NH 2 NH 2 ), NH 3 , BH 3 or a mixture thereof). In the embodiments of the present invention, available substrates may include: substrates containing one or more semiconductor materials selected from Si, Ge, SiGe, GaP, GaAs, SiC, SiGeC, InAs, and InP; Silicon On Insulator (SOI) substrates; quartz substrates; or glass substrates for display; polyimide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethylmethacrylate (PMMA), polycarbonate (PC), polyether flexible plastic substrates (such as sulfone (PES) and polyester); tungsten substrates, but not limited thereto. In a preferred embodiment of the ruthenium precursor, R in Chemical Formula 1 can be a substituted or unsubstituted C1 to C4 alkyl group, and more preferably, R can be a substituted or unsubstituted C1 to C3 alkyl group or a substituted or unsubstituted C1 to C2 alkyl group. In the best embodiment, the ruthenium precursor can be (isoprene)Ru(CO) 3 . In a method of manufacturing a ruthenium-containing film according to an exemplary embodiment, in addition to using (isoprene)Ru(CO) as a precursor 3 and H 2 , hydrazine (NH 2 NH 2 ), NH 3 , BH 3 or a reducing reaction gas of a mixture thereof, the corresponding film deposition conditions can be adjusted according to the desired structure or thermal properties of the film. Non-limiting examples of deposition conditions according to an exemplary embodiment may include the input flow rate, pressure, RF power, substrate temperature, etc. of a bubbler transfer gas that transfers (isoprene)Ru(CO) 3 evaporated in a bubbler container after loading the precursor, and the transfer gas flow rate of (isoprene)Ru(CO) 3 injected into the bubbler container is 1 cubic centimeter per minute (cc / min) to 1000 cubic centimeters per minute, the flow rate of the reducing reaction gas is 1 cubic centimeter per minute to 3000 cubic centimeters per minute, the pressure is 0.1 Torr to 100 Torr, the RF power is 50 watts to 1000 watts, and the substrate temperature can be adjusted within 80°C to 300°C and preferably 100°C to 300°C, but is not limited thereto. Preferably, based on 1 mole of (isoprene)Ru(CO) 3 , a reducing reaction gas according to an exemplary embodiment can be used in an amount of 0.1 mole to 500 moles, but is not limited thereto, and the reducing reaction gas can be adjusted according to the film deposition conditions. For example, in an atomic layer deposition (ALD) method, a plasma-enhanced atomic layer deposition (PEALD) method, or a chemical vapor deposition (CVD) method, based on 1 mole of (isoprene)Ru(CO) 3 , the reducing reaction gas can be used in an amount of preferably 1 mole to 100 moles, more preferably 1 mole to 50 moles, or even more preferably 2 moles to 30 moles. In a method of manufacturing a ruthenium-containing film according to an exemplary embodiment, a post-treatment step (B) can be performed in a reducing gas atmosphere. The reducing gas is the same as described above. The post-treatment step can be a heat treatment or a plasma treatment, where the heat treatment and the plasma treatment can be carried out at 200°C to 1000°C or at an RF power of 50 W to 1000 W for 1 minute to 4 hours, and preferably at 200°C to 800°C or at an RF power of 100 W to 500 W for 1 minute to 1 hour. The deposited film undergoes a post-treatment step (e.g., heat treatment, plasma treatment, and / or similar steps), which can increase the film density, improve the crystallinity, and reduce the resistivity by removing impurities to form a ruthenium film having a resistivity of 25 μΩ·cm or less than 25 μΩ·cm. The ruthenium film deposition step (A) and the post-treatment step (B) are repeatedly carried out until the ruthenium film has a desired thickness. In the method for manufacturing a ruthenium-containing film according to an exemplary embodiment, the optimal precursor (isoprene)Ru(CO) 3 is supplied into the chamber together with a carrier gas. Specifically, the carrier gas can be at least one or both selected from nitrogen (N 2 ), hydrogen, argon, and helium and is a desired combination of a specific reduction reaction gas of the present invention and at least one or both inert gases selected from nitrogen (N 2 ), argon, and helium. The ruthenium-containing film can be any film formed within the range recognized by those skilled in the art of manufacturing ruthenium-containing films by supplying ruthenium precursors by vapor. As a specific and practical example, the ruthenium-containing film can generally be a ruthenium film, a ruthenium oxide film, or a mixed film having conductivity, but in addition, various high-quality ruthenium-containing films can be manufactured within the range recognized by those skilled in the art. The ruthenium-containing film can be formed by repeating a process including a deposition step (A), a post-treatment step (B), and an optional purge step (C) as one cycle for 1 to 400 cycles. In addition, the ruthenium-containing film according to the exemplary embodiment can have a resistivity of less than or equal to 25 μΩ·cm, preferably less than or equal to 24 μΩ·cm, more preferably less than or equal to 23 μΩ·cm, and a carbon content of less than or equal to 2 atomic %, preferably less than or equal to 1.8 atomic %, and more preferably less than or equal to 1.6 atomic %. Furthermore, the ruthenium-containing film according to the exemplary embodiment can have an oxygen content of less than or equal to 1 atomic %, preferably less than or equal to 0.8 atomic %, and more preferably less than or equal to 0.5 atomic %. In addition, the ruthenium-containing film according to the exemplary embodiment can have a nitrogen content greater than 0 and less than 3 atomic %. In addition, the ruthenium-containing film according to an exemplary embodiment may have a hydrogen content of less than or equal to 7 atomic %, preferably less than or equal to 6.5 atomic %, and more preferably less than or equal to 6.2 atomic %. The method for manufacturing a ruthenium-containing film according to the present invention may perform heat treatment or plasma treatment as a post-treatment step subsequently performed after a deposition process using a ruthenium-based hydrocarbon compound represented by Chemical Formula 1 as a specific ruthenium precursor and a reducing reaction gas (e.g., H 2 , hydrazine (NH 2 NH 2 ), NH 3 , BH 3 or a mixture thereof) to form a ruthenium-containing film having high purity, high density, and high durability. Specifically, a ruthenium-based hydrocarbon compound represented by Chemical Formula 1 as a ruthenium precursor and a reducing reaction gas (e.g., H 2 , hydrazine (NH 2 NH 2 ), NH 3 , BH 3 or a mixture thereof) can be used to significantly improve thermal stability, and in addition, it is necessary to include a post-treatment step to further provide a ruthenium-containing film having high purity. By forming a ruthenium-containing film using a reducing reaction gas, impurities contained in the ruthenium-containing film are minimized. If a gas other than the reducing reaction gas is used as the reaction gas, substances contained in the reaction gas may remain in the ruthenium-containing film as impurities, thereby deteriorating the purity of the ruthenium film. Therefore, in the ruthenium film, a ruthenium content can be achieved at a high content of 90 atomic % or greater than 90 atomic %, the carbon content can be less than or equal to 2 atomic %, the oxygen content can be 1 atomic % or less than 1 atomic %, the nitrogen content can be less than 3 atomic %, and the hydrogen content can be reduced to 7 atomic % or less than 7 atomic %. In addition, the ruthenium-containing film formed according to the above process may have a resistivity of 25 μΩ·cm or less than 25 μΩ·cm, preferably 23 μΩ·cm or less than 23 μΩ·cm, and more preferably 21 μΩ·cm or less than 21 μΩ·cm. In the following, the present disclosure will be explained in more detail by the following examples. The terms or words used in this specification and the claims should not be construed as being limited to the ordinary meaning or dictionary meaning of the terms or words, and based on the principle that the inventor can appropriately define the concept of the terms and thus explain his or her invention in the best way, the terms or words should be construed as having meanings and concepts consistent with the technical idea of the present invention. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only one of the most desired embodiments of the present disclosure and do not represent all the technical ideas of the present disclosure, so it should be understood that when applying for this application, there are various equivalent structures and modifications that can replace the embodiments described in this specification and the configurations shown in the drawings. In addition, all the following examples are implemented using a commercial showerhead-type 200 millimeter (mm) single-wafer chemical vapor deposition (PECVD) apparatus (CN1, Atomic Premium) using a known chemical vapor deposition (CVD) method. In addition, the examples can be implemented using a commercial showerhead-type 200 millimeter single-wafer atomic layer deposition (ALD) apparatus (CN1, Atomic Premium) using a known atomic layer deposition (ALD) method. The resistivity of the deposited ruthenium-containing film is measured using a sheet resistance meter (4-point probe, DASOLENG, ARMS-200C), the thickness is measured using a transmission electron microscope (FEI (Netherlands) Tecnai G² F30S-Twin), and the composition of the film is analyzed using time-of-flight - elastic recoil detection (TOF-ERD) of NEC Corporation of Japan. Example: Manufacture of ruthenium-containing film Example 1: Manufacture of ruthenium-containing film applied with Compound 1 (including post-treatment steps) In the chemical vapor deposition method, ((isoprene)Ru(CO) 3 , Compound 1) is used as a Ru-containing precursor compound and hydrogen (H 2 ) is used as a reduction reaction gas to form a ruthenium-containing film. Subsequently, post-treatment that will be repeated using hydrogen plasma is performed to form a ruthenium-containing film. Specifically, silicon oxide is used as the substrate and the substrate is maintained at 250 °C. Compound 1 is loaded into a stainless-steel bubbler container and then maintained at 24 °C. Then, the evaporated Compound 1 in the stainless-steel bubbler container is transferred into the reaction chamber by supplying argon gas (50 standard cubic centimeters per minute) as the carrier gas for 20 seconds (0.016 grams). At the same time, hydrogen gas (2000 standard cubic centimeters per minute) is supplied to the reaction chamber for 20 seconds to form a ruthenium-containing film. Here, the reaction chamber is maintained at a pressure of 1.4 Torr. Then, argon gas (3000 standard cubic centimeters per minute) is used for 30 seconds to remove reaction by-products and residual reaction gases. The substrate with the ruthenium-containing film in the reaction chamber is subjected to hydrogen plasma post-treatment. The substrate is maintained at the same temperature of 250 °C, and hydrogen gas (2000 standard cubic centimeters per minute) and argon gas (400 standard cubic centimeters per minute) are supplied for 120 seconds. Here, the reaction chamber is maintained at a pressure of 5 Torr, and an RF power of 13.56 megahertz (MHz) is supplied at 100 watts. Finally, argon gas (3000 standard cubic centimeters per minute) is used for 30 seconds to remove reaction by-products and residual reaction gases. The above process is repeated 20 times to form a ruthenium-containing film. The formed ruthenium film is evaluated for thickness by transmission electron microscope (TEM) analysis, and the TEM analysis results and TOF-ERD analysis results under detailed reaction conditions are shown in Table 1. Comparative Example 1: Manufacture of a ruthenium-containing film to which Compound 1 is applied (excluding the post-treatment step) A ruthenium-containing film was produced in the same manner as in Example 1 except that the hydrogen plasma post-treatment was not performed. The ruthenium film was evaluated for thickness by TEM analysis, and the TEM analysis results and TOF-ERD analysis results under detailed reaction conditions are provided in Table 1. Comparative Example 2: Manufacture of a ruthenium-containing film to which Compound 2 is applied Except for using (Compound 2) instead of Compound 1 as the Ru-containing precursor compound, a ruthenium-containing film was formed in the same manner as in Example 1. The ruthenium film was evaluated for thickness by TEM analysis, and the TEM analysis results and TOF-ERD analysis results under detailed reaction conditions are provided in Table 1. (Table 1) Evaluation 1: Thermogravimetric analysis (TGA) and vapor pressure analysis The weight change (%) per temperature of Compound 1 and Compound 2 was measured by TGA using a Linseis STA PT100 (Germany) and increasing the temperature to 500 °C at 10 °C per minute in a nitrogen atmosphere, and the results are shown in Table 2 and Figure 3. In addition, the temperature representing a vapor pressure of 1 Torr was measured, and then the temperature was shown in Table 2. Figure 3 is a graph showing the TGA results of the ruthenium precursor. Referring to Figure 3 and Table 2, for TGA50% (the temperature at which the weight is reduced by 50%), Compound 1 and Compound 2 were compared. Compound 2 exhibited a TGA50% of 130 °C, but Compound 1 according to the present invention exhibited a TGA50% of 115 °C, which confirmed the improvement in volatility. In addition, the vapor pressure (V.P.) according to temperature was also consistent with the volatility. Comparing the temperatures indicating a vapor pressure of 1 Torr, it was proven that Compound 1 had a high vapor pressure at 24 °C, which was much lower than the vapor pressure of Compound 2 (54 °C at 1 Torr). Evaluation 2: Differential Scanning Calorimetry (DSC) Analysis The heat flow with temperature change was measured by using a differential scanning calorimeter (Mettler Toledo DSC3), and the results are shown in Table 2 and Figure 4. The DSC (differential scanning calorimetry) analysis was set within a temperature range of 25 °C to 500 °C at a temperature increase rate of 10 °C per minute. Figure 4 is a graph showing the measurement of the change in heat flow with temperature using a differential scanning calorimeter (Setaram instrument, Sensys evo DSC) with a ruthenium precursor. Referring to Figure 4 and Table 2, in the thermal analysis by DSC (differential scanning calorimetry), Compound 1 exhibited a main peak of 205 °C or greater than 205 °C as the maximum heat flow, which confirmed the excellent thermal stability compared to Compound 2 that exhibited a main peak of 197 °C or greater than 197 °C as the maximum heat flow. (Table 2) Evaluation 3: Evaluation of Room Temperature Storage Stability Six samples prepared by filling 1 milliliter of Compound 1 as a ruthenium precursor into a stainless steel bubbler container were stored in a glove box at room temperature under an argon atmosphere. Each sample was analyzed after 1 month, 2 months, 3 months, 6 months, 9 months, and 12 months to check the degree of decomposition and purity by 1H - Nuclear Magnetic Resonance (NMR), and the results are shown in Table 3 and Figure 5. Figure 5 is a graph showing the room - temperature storage stability of the ruthenium precursor Compound 1 of the present invention. Referring to Figure 5 and Table 3, each sample similarly maintained an initial 3N quality (> 99.9%) for 12 months immediately after production, and thus exhibited excellent long - term storage stability. Room temperature refers to a temperature of 22°C to 27°C. (Table 3) Evaluation 4: Evaluation of the step - coating characteristics By using ((isoprene)Ru(CO) 3 , Compound 1) as the Ru - containing precursor compound and using hydrogen gas (H 2 ) as the reduction reaction gas, a ruthenium - containing thin film was formed in a chemical vapor deposition method. Subsequently, the film was subjected to post - treatment by repeating the use of hydrogen plasma. Specifically, a titanium nitride layer pattern with an aspect ratio of 7:1 was used as the substrate and the substrate was maintained at 250°C, and Compound 1 was loaded into a stainless steel bubbler container and then maintained at 24°C. Compound 1 evaporated in the stainless steel bubbler container was transferred to the reaction chamber by supplying argon gas (50 standard cubic centimeters per minute) as the transfer gas for 20 seconds (0.016 grams). At the same time, hydrogen gas (2000 standard cubic centimeters per minute) was supplied for 20 seconds, thereby forming a ruthenium - containing thin film. Here, in the reaction chamber, the pressure was maintained at 1.4 Torr. Then, argon gas (3000 standard cubic centimeters per minute) was used to remove reaction by - products and residual reaction gases for 5 seconds. Subsequently, the formed ruthenium - containing thin - film substrate was subjected to hydrogen plasma post - treatment in the same reaction chamber. The substrate was also maintained at 250°C and hydrogen gas (2000 standard cubic centimeters per minute) and argon gas (400 standard cubic centimeters per minute) were supplied for 120 seconds. Here, in the reaction chamber, the pressure was maintained at 5 Torr and an RF power of 13.56 MHz was supplied at 100 watts. Finally, argon gas (3000 standard cubic centimeters per minute) was used to remove reaction by - products and residual reaction gases for 5 seconds. The above - mentioned entire process was repeated 4 times, thereby forming a ruthenium - containing thin film. The detailed thin film manufacturing conditions are shown in Table 4 below. TEM analysis was performed on the formed ruthenium thin film, and the results of evaluating the thickness and step coverage characteristics of the ruthenium-containing thin film are shown in Table 5 and FIG. 6. (Table 4) (Table 5) Referring to Table 5 and FIG. 6, a thin film with high uniformity was formed at a thin film thickness of 22 Å to 25 Å. Although the present disclosure has been specifically shown and described with reference to exemplary embodiments of the present disclosure, it should be understood that the present invention is not limited to the disclosed exemplary embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. (A): Deposition step / Ruthenium thin film deposition step (B): Post-treatment step (C): Purge step (D): Cycle FIG. 1 is a schematic diagram illustrating a method for manufacturing a ruthenium-containing thin film according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating a method for manufacturing a ruthenium-containing thin film according to Comparative Example 1. FIG. 3 is a graph showing the results of thermogravimetric analysis (TGA) of a ruthenium precursor. FIG. 4 is a graph showing the measurement of the change in heat flow with temperature using a differential scanning calorimeter (SETARAM Instrumentation, Sensys evo DSC) with a ruthenium precursor. FIG. 5 is a graph showing the room temperature storage stability of ruthenium precursor compound 1 of the present invention. FIG. 6 is a graph showing the results of evaluating the step coverage characteristics by transmission electron microscope (TEM) analysis of the ruthenium thin film according to Example 1. (A): Deposition step / Ruthenium thin film deposition step (B): Post-treatment step (C): Purge step (D): Cycle

Claims

1. A method for manufacturing a ruthenium-containing thin film, comprising supplying a transport gas and a ruthenium precursor represented by Formula 1 to a chamber on which a substrate is mounted, and depositing a ruthenium-containing thin film on the substrate while injecting a reducing reaction gas into the chamber; and a post-processing step comprising performing plasma treatment in a reducing reaction gas atmosphere, wherein the reducing reaction gas is at least one selected from H2, hydrazine (NH2NH2), NH3 and BH3: [Formula 1] wherein in Formula 1, R is a substituted or unsubstituted C1 to C5 alkyl group.

2. The method of manufacturing a ruthenium-containing thin film as claimed in claim 1, wherein the temperature of the substrate is maintained at 80°C to 300°C during the supply.

3. The method for manufacturing a ruthenium-containing thin film as claimed in claim 1, wherein the reducing reaction gas is injected in an amount of 0.1 mol to 500 mol per mol of the ruthenium precursor represented by chemical formula 1.

4. The method of manufacturing a ruthenium-containing thin film as claimed in claim 1, wherein the plasma treatment is performed at a radio frequency power of 50 watts to 1000 watts.

5. The method for manufacturing a ruthenium-containing thin film as claimed in claim 1, wherein the method further comprises purging by supplying an inert gas.

6. The method for manufacturing a ruthenium-containing thin film as claimed in claim 1, wherein the resistivity of the ruthenium-containing thin film is less than or equal to 25 micro-ohms per centimeter.

7. The method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the carbon content is less than or equal to 2 atoms.

8. The method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the oxygen content is less than or equal to 1 atom.

9. The method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the nitrogen content is greater than 0 and less than 3 atoms.

10. The method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the hydrogen content is less than or equal to 7 atoms.

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