TW202502796A - Method of manufacturing a ruthenium-containing thin film - Google Patents

Abstract

A method of manufacturing a ruthenium-containing thin film includes supplying a transport gas and a ruthenium precursor represented by Chemical Formula 1 into a chamber in which a substrate is mounted, depositing a ruthenium-containing thin film on the substrate while injecting a reducing reaction gas into the chamber; and a post-treatment process comprising at least one of thermal treatment in a reducing reaction gas atmosphere and plasma treatment in a reducing reaction gas atmosphere, wherein the reducing reaction gas is at least one selected from H ₂, hydrazine (NH ₂NH ₂), NH ₃, and BH ₃.

Description

Method for producing ruthenium-containing thin film

The present disclosure relates to a method for manufacturing a ruthenium-containing thin film, and more specifically to a method for manufacturing a ruthenium-containing thin film including post-processing, wherein the post-processing includes at least one of depositing the ruthenium-containing thin film using a ruthenium precursor of a specific structure and a reducing reaction gas, performing a heat treatment in a reducing reaction gas atmosphere, and performing a plasma treatment in a reducing reaction gas atmosphere. [Cross-reference to related applications]

This application claims priority to and benefits of Korean Patent Application No. 10-2023-0035752 filed on March 20, 2023 with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.

Ruthenium (Ru) thin films can be used as seed layers or electrodes (e.g., gates of transistors or capacitors) in the wiring structure of semiconductor devices. As semiconductor devices become more highly integrated and smaller in size, ruthenium (Ru) thin films used in semiconductor devices also require 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), and physical vapor deposition (PVD) are being studied. Recently, as the size of semiconductor devices has been reduced (which has 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 uniformity and coating properties of thin films.

The atomic layer deposition (ALD) method for forming ruthenium thin films has traditionally used Ru(OD) ₃ [tri(2,4-octanedionato)ruthenium(III)], Ru(EtCP) ₂ [bis(ethylcyclopentadienyl)ruthenium(II)], etc. as ruthenium raw materials. However, among these, Ru(OD) ₃ contains oxygen, making it difficult to deposit pure ruthenium on the reaction substrate, and also has the problem of forming RuO _x on a portion of the substrate.

In addition, Ru(EtCP) ₂ is a cyclopentadiene compound, which makes it difficult for ruthenium atoms to break chemical bonds and exist independently, thereby causing the problem of leaving a large amount of impurities on the ruthenium film. In addition, Ru(EtCP) ₂ is not easily decomposed by using _O2 plasma and is therefore deposited to form a _RuO2 film. Therefore, the _RuO2 film needs to be reduced again using _H2 to obtain a Ru film, which is another problem.

Chemical vapor deposition is also being studied to develop a process for forming a ruthenium thin film, but (cyclohexadiene)Ru(CO) ₃ used as a ruthenium raw material in the process has a problem of decomposition during the deposition process due to a significant decrease in thermal stability. Even materials with improved thermal stability in conventional technologies still have problems such as reduced volatility or deterioration in resistivity.

Therefore, there is a need for a method of producing high purity ruthenium-containing thin films by reducing the impurity content while also improving the film properties (e.g., room temperature thermal stability and resistivity).

One aspect of the present disclosure provides a method for manufacturing a ruthenium-containing thin film having a 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 film by a post-treatment step.

An embodiment of the present invention provides a method for manufacturing a ruthenium-containing thin film, the method comprising: supplying a transport gas and a ruthenium precursor represented by Chemical Formula 1 into a chamber in which a substrate is installed, and depositing the ruthenium-containing thin film on the substrate while injecting a reducing reaction gas into the chamber; and a post-treatment process comprising at least one of performing a heat treatment in a reducing reaction gas atmosphere and performing a 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 .

[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 supply.

The reducing reaction gas may be injected in an amount of 0.1 mol to 500 mol per 1 mol of the ruthenium precursor represented by Chemical Formula 1.

Heat treatment can be carried out at a temperature between 200°C and 1000°C.

Plasma processing can be performed at radio frequency (RF) powers ranging from 50 watts to 1000 watts.

The method of manufacturing a ruthenium-containing thin film may further include performing purging by supplying an inert gas.

The specific resistance of the ruthenium-containing film can be less than or equal to 25 microohm·cm.

The ruthenium-containing film may have a carbon content less than or equal to 2 atomic %.

The ruthenium-containing thin film may have an oxygen content of less than or equal to 1 atomic %.

The ruthenium-containing thin film may have a nitrogen content greater than 0 and less than 3 atomic %.

The ruthenium-containing thin film may have a hydrogen content of less than or equal to 7 atomic %.

According to the embodiments, the use of a ruthenium precursor having a specific structure improves thermal stability, prevents decomposition under storage conditions and usage conditions, improves film resistivity through post-processing steps, and provides a ruthenium-containing thin film with high purity.

The present disclosure will be described more fully hereinafter 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.

In order to clearly describe the present disclosure, parts irrelevant 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 is not necessarily limited to the size and thickness shown. In the drawings, the thickness of layers, regions, etc. are exaggerated for clarity. In the drawings, the thickness of some layers and regions is exaggerated for ease of explanation.

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 may be directly on the other element or there may be intervening elements. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements. Furthermore, disposed "on" or "above" a reference portion means disposed above or below the reference portion and does not necessarily mean "on" or "above" in the relative direction of gravity.

In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

When no additional definition is provided, "substituted" as used herein means that at least one hydrogen atom of the compound is replaced by a substituent selected from the group consisting of a halogen atom (F, Br, Cl or I), a hydroxyl group, an alkoxy group, a nitro group, a cyano group, an amine group, an azido group, an amido group, a hydrazine group, a hydrazone group, a carbonyl group, a carbamyl group, a hydroxyl group, an ester group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a vinyl group, a C1 to C2 ... C20 alkyl, C2 to C20 alkenyl, C2 to C20 alkynyl, C6 to C30 aryl, C7 to C30 arylalkyl, C6 to C30 allyl, C1 to C30 alkoxy, C1 to C20 heteroalkyl, C3 to C20 heteroarylalkyl, C3 to C30 cycloalkyl, C3 to C15 cycloalkenyl, C6 to C15 cycloalkynyl, C3 to C30 heterocycloalkyl, and combinations thereof.

When no definition is otherwise provided, "hetero" as used herein means containing 1 to 10 hetero atoms independently selected from N, O, S and P.

In addition, in this specification, an acrylic polymer refers to an acrylic polymer and a methacrylic polymer.

Hereinafter, a method for manufacturing a ruthenium-containing thin film according to an embodiment will be described.

The method for manufacturing a ruthenium-containing thin film according to an embodiment includes: supplying a transport gas and a ruthenium precursor represented by Chemical Formula 1 into a chamber in which a substrate is installed, depositing the ruthenium-containing thin film on the substrate while injecting a reducing reaction gas into the chamber; and a post-treatment process including at least one of performing a heat treatment in a reducing reaction gas atmosphere and performing a 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 .

[Chemical formula 1] In Chemical Formula 1, R is a substituted or unsubstituted C1 to C5 alkyl group.

The present invention uses a ruthenium precursor represented by Chemical Formula 1, uses a reducing reaction gas (e.g., _H2 , _{hydrazine (NH2NH2 )} , _NH3 , _BH3 or a mixture thereof), and simultaneously includes a post-treatment step of performing a heat treatment and/or a plasma treatment in an atmosphere of the reducing reaction gas, and thus improves thermal stability by a process that essentially includes 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 thin film.

Hereinafter, the method for manufacturing the above-mentioned ruthenium-containing thin film will be explained with reference to FIG. 1 in comparison with FIG. 2 showing the method for manufacturing the ruthenium-containing thin film according to Comparative Example 1. FIG. 1 is a schematic diagram illustrating a method for manufacturing a ruthenium-containing thin film according to an embodiment of the present invention, and FIG. 2 is a schematic diagram illustrating a method for manufacturing a ruthenium-containing thin film according to Comparative Example 1.

1 , manufacturing a ruthenium-containing film may include: supplying a transfer gas and a ruthenium precursor represented by chemical formula 1 into a chamber in which a substrate is mounted, and depositing the ruthenium-containing film on the substrate when a reducing reaction gas is injected into the chamber (A); a post-treatment process including at least one of heat treatment in a reducing reaction gas atmosphere and plasma treatment in a reducing reaction gas atmosphere (B), and may further include purging by supplying an inert gas (C).

The method for manufacturing a ruthenium-containing thin film comprises repeating a deposition step (A), a post-treatment step (B) and a purging step (C) as a cycle, and performing such a cycle (D) until a desired film thickness is obtained.

In contrast, referring to FIG. 2 , a ruthenium-containing thin film may be manufactured by the following steps: a transfer gas and a ruthenium precursor represented by Chemical Formula 1 are supplied into a chamber in which a substrate is mounted, the ruthenium-containing thin film is deposited on the substrate while a reducing reaction gas is injected into the chamber (A), and then purged by additionally supplying an inert gas (C) without performing a separate post-processing step, the above being regarded as a cycle and such a cycle is repeated (D).

If a post-processing step is further included, the film resistivity can be increased and a ruthenium-containing film with high purity can be produced.

At this time, a purging step (C) may be optionally included as needed.

The deposition method may 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, atomic layer deposition (ALD) or chemical vapor deposition (CVD) may be desirably used.

In the method of manufacturing a ruthenium-containing thin film according to an embodiment of the present invention, a ruthenium precursor used as a precursor can be changed into a gas state by, for example, heating the thin film deposit and then introduced into a process chamber.

In the method for manufacturing a ruthenium-containing thin film according to an embodiment of the present invention, the reducing reaction gas can be changed into a gas state by a method such as heating and then introduced into a process chamber where a substrate adsorbed with a ruthenium precursor exists.

In the method for manufacturing a ruthenium-containing thin film according to an embodiment of the present invention, the ruthenium precursor and the reducing reaction gas may be supplied to the chamber organically or independently of each other and may be supplied simultaneously or sequentially.

In addition, the ruthenium precursor and the reducing reaction gas may be supplied to the chamber continuously or discontinuously, and the discontinuous supply may include a pulsed form.

In an embodiment, the deposition method may be a chemical vapor deposition (CVD) method, in which case the ruthenium precursor supply and the reducing reaction gas injection may be performed simultaneously.

In the method for producing a ruthenium-containing thin film according to an embodiment of the present invention, a purging step (C) may be performed at least one of before the post-treatment step or after the post-treatment step.

That is, the purge step may be performed before or after the post-treatment step, or may be performed before and after the post-treatment step, respectively, and the purge step may be optionally performed by supplying an inert gas into the chamber to exhaust unreacted ruthenium precursor gas, byproduct gas, or unreacted reducing reaction gas. The inert gas may be any one or two or more selected from nitrogen ( _N2 ), argon, and helium. The injection amount of the purge gas is not limited, but specifically, the purge gas may be supplied at an injection amount ranging from 800 standard cubic centimeter per minute (sccm) to 5,000 sccm, and more specifically, from 1,000 sccm to 3,000 sccm.

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, but can be maintained at 300°C or lower in the chamber, preferably between 80°C and 300°C, and the temperature range is a temperature range caused by the decomposition characteristics of the ruthenium compound used as a precursor and the reaction characteristics with other substances used as a reducing reaction gas (for example, _H2 , hydrazine ( _{NH2NH2 )} , _NH3 , _BH3 or a mixture thereof).

In the embodiments of the present invention, available substrates may include: a substrate containing one or more semiconductor materials selected from Si, Ge, SiGe, GaP, GaAs, SiC, SiGeC, InAs and InP; a Silicon On Insulator (SOI) substrate; a quartz substrate; or a glass substrate for display; polyimide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethylmethacrylate (PMMA), polycarbonate (PC), polyether flexible plastic substrates (for example, sulfone (PES) and polyester); tungsten substrates, but are not limited to these.

In a preferred embodiment of the ruthenium promotor, R in Formula 1 may be a substituted or unsubstituted C1 to C4 alkyl group, and more preferably, R may 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 promotor may be (isoprene)Ru(CO) ₃ .

In the method of manufacturing a ruthenium-containing thin film according to an exemplary embodiment, in addition to using (isoprene)Ru(CO) ₃ as _a precursor and a reducing reaction gas of _H2 , hydrazine ( _NH2NH2 ), _NH3 , _BH3 or a mixture thereof, the corresponding film deposition conditions may be adjusted according to the desired structure or thermal properties of the film.

Non-limiting examples of deposition conditions according to exemplary embodiments may include an input flow rate, pressure, RF power, substrate temperature, etc. of a bubbler transfer gas for transferring a precursor of (isoprene)Ru(CO) ₃ evaporated in the bubbler container after loading the precursor, and the (isoprene)Ru(CO)3 injected into the bubbler container. ₃ , the transport gas flow rate is 1 cubic centimeter/minute (cc/min) to 1000 cubic centimeter/minute, the flow rate of the reducing reaction gas is 1 cubic centimeter/minute to 3000 cubic centimeter/minute, the pressure is 0.1 Torr to 100 Torr, the RF power is 50 W to 1000 W, and the substrate temperature can be adjusted within 80°C to 300°C and preferably within 100°C to 300°C, but is not limited thereto.

Preferably, the reducing reaction gas according to the exemplary embodiment can be used in an amount of 0.1 mol to 500 mol based on 1 mol of (isoprene)Ru(CO) ₃ , but is not limited thereto, and the reducing reaction gas can be adjusted according to the thin 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, the reducing reaction gas can be used in an amount of preferably 1 mol to 100 mol, more preferably 1 mol to 50 mol, or even more preferably 2 mol to 30 mol based on 1 mol of (isoprene)Ru(CO) ₃ .

In the method for manufacturing a ruthenium-containing thin film according to an exemplary embodiment, the post-treatment step (B) may be performed under a reducing gas atmosphere.

The reducing gas is the same as described above.

The post-treatment step may be a heat treatment or a plasma treatment, wherein the heat treatment and the plasma treatment may be performed 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 post-processing steps (e.g., heat treatment, plasma treatment, and/or the like) which may increase film density, improve crystallinity, and reduce resistivity by removing impurities to form a ruthenium film having a resistivity of 25 micro-ohm·cm or less.

The ruthenium film deposition step (A) and the post-treatment step (B) are repeatedly performed until the ruthenium film has a desired thickness.

In the method for manufacturing a ruthenium-containing thin film according to an exemplary embodiment, the optimal precursor (isoprene) Ru(CO) ₃ can be supplied into the chamber together with a transfer gas. Specifically, the transfer gas can be at least one or two selected from nitrogen (N ₂ ), hydrogen, argon and helium and as a desired combination with the specific reducing reaction gas of the present invention, at least one or two inert gases selected from nitrogen (N ₂ ), argon and helium.

The ruthenium-containing thin film may be any thin film formed within the range recognized by a person skilled in the art of manufacturing a ruthenium-containing thin film by supplying a ruthenium precursor with vapor. As a specific and practical example, the ruthenium-containing thin film may generally be a ruthenium film, a ruthenium oxide film, or a mixed film thereof having conductivity, but in addition thereto, various high-quality ruthenium-containing thin films may be manufactured within the range recognized by a person skilled in the art.

A ruthenium-containing thin 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 may have a resistivity less than or equal to 25 microohm·cm, preferably less than or equal to 24 microohm·cm, and more preferably less than or equal to 23 microohm·cm, and a carbon content 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 %.

In addition, the ruthenium-containing thin film according to the exemplary embodiment may 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 thin film according to the exemplary embodiment may have a nitrogen content greater than 0 and less than 3 atomic %.

In addition, the ruthenium-containing thin film according to the 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 thin film according to the present invention may perform heat treatment or plasma treatment as a post-treatment step performed subsequently to a deposition process using a ruthenium hydrocarbon compound represented by Chemical Formula 1 as a specific ruthenium precursor and a reducing reaction gas ( _e.g. , _H2 , hydrazine ( _NH2NH2 ), _NH3 , _BH3 or a mixture thereof) to form a ruthenium-containing thin film having high purity, high density and high durability.

Specifically, a ruthenium hydrocarbon compound represented by Chemical Formula 1 as a ruthenium precursor and a reducing reaction gas (e.g., _H2 , hydrazine ( _{NH2NH2 )} , _NH3 , _BH3 or a mixture thereof) can be used to significantly improve thermal stability, and further, a post-treatment step is necessarily included, thereby providing a ruthenium-containing thin film with high purity.

By using a reducing reaction gas to form the ruthenium-containing thin film, impurities contained in the ruthenium-containing thin film can be 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 thin film as impurities, thereby deteriorating the purity of the ruthenium thin film.

Therefore, in the ruthenium film, the ruthenium content can be achieved at a high content of 90 atomic % or greater, the carbon content can be less than or equal to 2 atomic %, the oxygen content can be 1 atomic % or less, the nitrogen content can be less than 3 atomic %, and the hydrogen content can be reduced to 7 atomic % or less.

In addition, the ruthenium-containing film formed according to the above process may have a resistivity of 25 microohm·cm or less, preferably 23 microohm·cm or less, and even more preferably 21 microohm·cm or less.

Hereinafter, the present disclosure will be explained in more detail by the following examples. The terms or words used in this specification and the scope of the patent application should not be interpreted as being limited to the usual meaning or dictionary meaning of the terms or words, and based on the principle that the inventor can properly define the concept of the terms and thus explain his or her invention in the best way, the terms or words should be interpreted as the meaning and concept 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. 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 were performed using a commercialized spray head type 200 mm single wafer CVD (PECVD) equipment (CN1, Atomic Premium) using a known chemical vapor deposition (CVD) method. In addition, the examples can be performed using a commercialized spray head type 200 mm single wafer ALD equipment (CN1, Atomic Premium) using a known atomic layer deposition (ALD) method.

The resistivity of the deposited ruthenium-containing thin film was measured using a sheet resistance meter (4-point probe, DASOLENG, ARMS-200C), the thickness was measured using a transmission electron microscope (FEI (Netherlands) Tecnai G²F30S-Twin), and the composition of the film was analyzed using Time of Flight - Elastic Recoil Detection (TOF-ERD) of NEC Corporation (NEC). Example: Fabrication of ruthenium-containing thin film Example 1: Fabrication of ruthenium-containing thin film with compound 1 applied (including post-treatment step)

Used in chemical vapor deposition ((isoprene)Ru(CO) ₃ , Compound 1) is used as a Ru-containing precursor compound and hydrogen (H ₂ ) is used as a reducing reaction gas to form a ruthenium-containing thin film. Subsequently, a post-treatment is performed using hydrogen plasma, which is repeated to form a ruthenium-containing thin film.

Specifically, silicon oxide was used as a 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. Then, compound 1 evaporated in the stainless steel bubbler container was transferred to the reaction chamber by supplying argon (50 standard cubic centimeters/minute) as a transfer gas for 20 seconds (0.016 grams). At the same time, hydrogen (2000 standard cubic centimeters/minute) was supplied to the reaction chamber for 20 seconds to form a ruthenium-containing film. Herein, the reaction chamber was maintained at a pressure of 1.4 Torr. Then, argon (3000 standard cubic centimeters/minute) was used for 30 seconds to remove reaction byproducts and residual reaction gas. The substrate containing the ruthenium film was post-treated with hydrogen plasma in a reaction chamber. The substrate was maintained at the same temperature of 250°C, and hydrogen (2000 standard cubic centimeters/minute) and argon (400 standard cubic centimeters/minute) were supplied for 120 seconds. In this article, the reaction chamber was maintained at a pressure of 5 Torr, and 13.56 MHz RF power was supplied at 100 W. Finally, argon (3000 standard cubic centimeters/minute) was used for 30 seconds to remove reaction byproducts and residual reaction gases. The above process was repeated 20 times to form a ruthenium-containing film. The formed ruthenium thin film was evaluated with respect to 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: Fabrication of a ruthenium-containing thin film applied with compound 1 (excluding post-treatment steps)

A ruthenium-containing thin film was produced in the same manner as in Example 1, except that the hydrogen plasma post-treatment was not performed.

The ruthenium thin film was evaluated with respect to 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: Fabrication of a Ruthenium-Containing Thin Film Applying Compound 2

Except for use A ruthenium-containing thin film was formed in the same manner as in Example 1 except that (Compound 2) was used instead of Compound 1 as the Ru-containing precursor compound. The thickness of the ruthenium thin film was evaluated by TEM analysis, and the TEM analysis results and TOF-ERD analysis results under detailed reaction conditions are provided in Table 1. (Table 1) Film manufacturing conditions Example 1 Comparison Example 1 Comparison Example 2 Substrate temperature (°C) 250 250 200 Chemical gas reaction (Ruthenium deposition) Ru compound 1 precursor temperature (℃) twenty four twenty four - Ru compound 2 precursor temperature (℃) - - 34 Ru front drive bubble gas (standard cubic centimeters/minute) 50 50 10 Hydrogen (standard cubic centimeters/minute) 2000 2000 2000 Process pressure (support) 1.4 1.4 1.4 Process time (seconds) 40 800 47 Blow (argon) Argon (standard cubic centimeters per minute) 3000 3000 3000 Time (seconds) 30 30 30 Post-treatment (hydrogen plasma) Hydrogen (standard cubic centimeters/minute) 2000 - 2000 Argon (standard cubic centimeters per minute) 400 400 Process pressure (support) 5 5 RF Power (Watts) 100 100 Time (seconds) 120 120 Blow (argon) Argon (standard cubic centimeters per minute) 3000 - 3000 Time (seconds) 30 - 30 Total number of process repetitions Cycle 20 1 20 Thickness of Ruthenium-containing Film (Angstroms) 320 410 230 Resistivity of ruthenium-containing thin films (microohm·cm) twenty one 259 29 TOF-ERD Ru（%) 91.0 50.0 82.0 O (%) 0.5 0.0 3.0 C (%) 1.6 41.0 6.9 N (%) 0.7 0.0 3.0 H (%) 6.2 9.0 5.2 Assessment 1: Thermogravimetric analysis (TGA) and vapor pressure analysis

The weight change (%) of Compound 1 and Compound 2 was measured by TGA performed at 10° C. per minute up to 500° C. under a nitrogen atmosphere using Linseis STA PT100 (Germany), and the results are shown in Table 2 and FIG. 3 .

In addition, the temperature representing the vapor pressure of 1 Torr was measured and then shown in Table 2.

FIG3 is a graph showing TGA results of ruthenium precursors.

3 and Table 2, when comparing Compound 1 and Compound 2 with respect to TGA50% (which is the temperature at which the weight is reduced by 50%), Compound 2 exhibited a TGA50% of 130° C., but Compound 1 according to the present invention exhibited a TGA50% of 115° C., which confirmed that volatility was improved.

In addition, the vapor pressure (V.P.) according to temperature is also consistent with volatility. Comparison of the temperature indicating the vapor pressure of 1 Torr shows that compound 1 has a high vapor pressure at 24°C, which is much lower than the vapor pressure of compound 2 (54°C at 1 Torr). Evaluation 2: Differential scanning calorimetry (DSC) analysis

The heat flow as a function of temperature was measured by using a differential scanning calorimeter (Mettler Toledo DSC3), and the results are shown in Table 2 and FIG. 4 .

DSC (Differential Scanning Calorimetry) analysis was set in the temperature range of 25°C to 500°C at a temperature increase rate of 10°C/min.

FIG4 is a graph showing the variation of heat flow with temperature measured using a differential scanning calorimeter (Sentral Instruments, Sensys evo DSC) of a ruthenium precursor.

Referring to FIG. 4 and Table 2, in thermal analysis by DSC (differential scanning calorimetry), compound 1 exhibited a main peak at 205°C or more as the maximum heat flow, compared to compound 2 which exhibited a main peak at 197°C or more as the maximum heat flow, which confirmed that excellent thermal stability was ensured. (Table 2) Compound 1 Compound 2 Steam pressure at 1 Torr (℃) 24℃ 54℃ TG50% temperature (℃)/residue (%) 115℃/＜3% 130℃/＜3% DSC (℃) 205℃ 197℃ Assessment 3: Assessment of room temperature storage stability

Six samples prepared by filling 1 ml of compound 1 as a ruthenium precursor in 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-NMR, and the results are shown in Table 3 and FIG. 5 .

FIG5 is a graph showing the room temperature storage stability of the ruthenium precursor compound 1 of the present invention.

Referring to FIG. 5 and Table 3, each sample similarly maintained the 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 between 22°C and 27°C. (Table 3) Storage period (month) References 1 2 3 6 9 12 Room temperature Determination (%) 99.91 99.90 99.92 99.90 99.90 99.92 99.90 Change rate (%) -0.01 +0.01 -0.01 -0.01 +0.01 -0.01 Assessment 4: Assessment of step coating characteristics

By using A ruthenium-containing thin film is formed by chemical vapor deposition using ((isoprene)Ru(CO) ₃ , Compound 1) as a Ru-containing precursor compound and hydrogen (H ₂ ) as a reducing reaction gas. Subsequently, the film is repeatedly post-treated by using hydrogen plasma.

Specifically, a titanium nitride layer pattern with an aspect ratio of 7:1 was used as a 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 (50 standard cubic centimeters/minute) as a transfer gas for 20 seconds (0.016 grams). At the same time, hydrogen (2000 standard cubic centimeters/minute) was supplied for 20 seconds to form a ruthenium-containing film. In this article, the pressure in the reaction chamber was maintained at 1.4 Torr. Then, argon (3000 standard cubic centimeters/minute) is used to remove reaction byproducts and residual reaction gases for 5 seconds. The formed ruthenium-containing thin film substrate is then subjected to hydrogen plasma post-treatment in the same reaction chamber. The substrate is also maintained at 250°C and supplied with hydrogen (2000 standard cubic centimeters/minute) and argon (400 standard cubic centimeters/minute) for 120 seconds. In this article, in the reaction chamber, the pressure is maintained at 5 Torr and 13.56 MHz RF power is supplied at 100 Watts. Finally, argon (3000 standard cubic centimeters/minute) is used to remove reaction byproducts and residual reaction gases for 5 seconds. The above entire process is repeated 4 times to form a ruthenium-containing thin film.

The detailed film manufacturing conditions are shown in Table 4 below. The formed ruthenium thin film was subjected to TEM analysis, and the results of the evaluation of the thickness and step coverage characteristics of the ruthenium-containing thin film are shown in Table 5 and FIG. 6. (Table 4) Film manufacturing conditions Example 1 Substrate temperature (°C) 250 Chemical gas reaction (Ruthenium deposition) Ru compound 1 precursor temperature (℃) twenty four Ru precursor bubble gas (standard cubic centimeters/minute) 50 Hydrogen (standard cubic centimeters/minute) 2000 Process pressure (support) 1.4 Process time (seconds) 20 Blow (argon) Argon (standard cubic centimeters per minute) 3000 Time (seconds) 5 Post-treatment (hydrogen plasma) Hydrogen (standard cubic centimeters/minute) 2000 Argon (standard cubic centimeters per minute) 400 Process pressure (support) 5 RF Power (Watts) 100 Time (seconds) 120 Blow (argon) Argon (standard cubic centimeters per minute) 3000 Time (seconds) 5 Total number of process repetitions Cycle 4 Thickness of Ruthenium-containing Film (Angstroms) 22 to 25 Stair Coverage (%) Top thickness (THK) Reference 87 (Table 5) Location Ruthenium film thickness (Angstroms) Top Central bottom 25 Angstroms 22 Angstroms 22 Angstroms Step coverage characteristics (%) (top reference) - 87% 87%

Referring to Table 5 and FIG. 6 , a thin film having high uniformity was formed at a film thickness of 22 angstroms to 25 angstroms.

While the present disclosure has been particularly shown and described with reference to exemplary embodiments thereof, 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 film deposition step (B): Post-treatment step (C): Blowing step (D): Circulation

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 change in heat flow with temperature using a differential scanning calorimeter (SETARAM Instrumentation, Sensys evo DSC) of a ruthenium precursor. FIG. 5 is a graph showing the room temperature storage stability of the ruthenium precursor compound 1 of the present invention. FIG6 is a graph showing the results of evaluating the step coverage characteristics by transmission electron microscopy (TEM) analysis of the ruthenium thin film according to Example 1.

(A): Deposition step/Ruthenium thin film deposition step

(B): Post-processing steps

(C): Blowing steps

(D): Cycle

Claims (10)

A method for manufacturing a ruthenium-containing thin film, comprising supplying a transport gas and a ruthenium precursor represented by Chemical Formula 1 into a chamber in which a substrate is installed, and depositing the ruthenium-containing thin film on the substrate while injecting a reducing reaction gas into the chamber; and a post-treatment process, comprising at least one of performing a heat treatment in a reducing reaction gas atmosphere and performing a 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 : [Chemical Formula 1] In Formula 1, R is a substituted or unsubstituted C1 to C5 alkyl group. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the temperature of the substrate is maintained at 80°C to 300°C during the supply. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the reducing reaction gas is injected in an amount of 0.1 mol to 500 mol per 1 mol of the ruthenium precursor represented by chemical formula 1. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the heat treatment is performed at a temperature of 200°C to 1000°C, and the plasma treatment is performed at an RF power of 50W to 1000W. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the method further includes blowing by supplying an inert gas. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the specific resistance of the ruthenium-containing thin film is less than or equal to 25 micro-ohm·cm. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the carbon content is less than or equal to 2 atomic %. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the oxygen content is less than or equal to 1 atomic %. A 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 atomic %. A method for manufacturing a ruthenium-containing thin film as described in claim 1, wherein the hydrogen content is less than or equal to 7 atomic %.

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