Thin film formation method, semiconductor substrate and semiconductor device manufactured thereby

Abstract

The present invention relates to a thin film formation method, and a semiconductor substrate and semiconductor device manufactured thereby. By applying a specific reducing agent, the uniformity of the film thickness can be significantly improved, even when the thin film is formed on a highly integrated substrate or a substrate having a complex structure, and the film quality can be effectively improved by reducing impurities and improving the film density and resistivity.

Description

[Technical Field]

[0001] The present invention relates to a thin film formation method, and a semiconductor substrate and semiconductor device manufactured thereby. More specifically, the present invention relates to a thin film formation method that, by applying a specific reducing agent, provides a reduction effect at a relatively low process temperature at which a precursor does not thermally decompose, thereby significantly improving the film thickness uniformity of the thin film, significantly reducing impurities, and improving film quality, even when the thin film is formed on a highly integrated substrate or a substrate having a complex structure, and a semiconductor substrate and semiconductor device manufactured thereby. [Background technology]

[0002] In recent years, with the demand for higher performance and higher integration of semiconductor elements, there has been a demand for electrode materials or diffusion barrier film materials with reduced resistivity.

[0003] These materials are available in the form of thin films using atomic layer deposition (ALD) processes, but the reduction processes used to form these thin films currently require the use of very strong reducing agents and high thermal energy.

[0004] However, extremely strong reducing agents such as N2H4 hydrazine are highly toxic and dangerous, making them difficult to handle. In addition, the application of high thermal energy can cause the precursor compound to thermally decompose, which can lead to poor step coverage, voids, or seams in highly integrated substrates or complex substrates with high aspect ratios.

[0005] In addition, impurities (C, Cl) derived from the ligands of the precursor compound were detected in the thin film. - , F - Not only do these substances infiltrate and contaminate the thin film, but they also disrupt the crystal arrangement and reduce the density of the thin film, which can lead to problems such as impaired electrical conductivity due to low density.

[0006] Therefore, there is a need to develop a thin film formation method that can form a uniform thin film even on a complex structure, with a low amount of residual impurities, and that can significantly improve the uniformity of the film thickness, as well as semiconductor substrates and the like manufactured using this method.

[0007] [Prior art document]

[0008] [Patent documents]

[0009] Republic of Korea Publication Patent No. 2019-0141071 Summary of the Invention [Problem to be solved by the invention]

[0010] In order to solve the above-mentioned problems of the prior art, the present invention aims to provide a method for forming a high-quality thin film with excellent film thickness uniformity even when the thin film is formed on a substrate having a complex structure by effectively improving the thin film and deposition characteristics, such as reducing impurities and improving resistivity, by applying a specific reducing agent, and a semiconductor substrate manufactured thereby.

[0011] That is, an object of the present invention is to improve film quality such as electrical properties, dielectric properties, and thin film density by using a predetermined reducing agent.

[0012] The above and other objects of the present invention can be achieved by the present invention described below. [Means for solving the problem]

[0013] In order to achieve the above object, the present invention provides:

[0014] Injecting a precursor compound into a chamber to adsorb it on the substrate surface; and injecting a reducing agent into the chamber to form a deposited film;

[0015] The thin film forming method is characterized in that the reducing agent is at least one selected from the group consisting of hydrogen iodide, hydrogen iodide water, hydrogen bromide and hydrogen bromide water.

[0016] The reducing agent is 3N to 15N hydrogen iodide alone, a gas mixture of 1 to 99% by weight of 3N to 15N hydrogen iodide and the balance of an inert gas so that the total amount is 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 3N to 15N hydrogen iodide and the balance of water so that the total amount is 100% by weight, where the inert gas can be nitrogen, helium, or argon having a purity of 4N to 9N.

[0017] The thin film may be a laminated film of one or more materials selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti.

[0018] The thin film may be a nitride film, a metal film, or a selective thin film thereof formed on the entire substrate or a portion of the substrate.

[0019] The precursor compound may be a molecule composed of one or more species selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti, and may be a compound having a vapor pressure at 25°C of more than 0.01 mTorr and not more than 100 Torr.

[0020] The thin film formation method may include the steps of injecting a precursor compound into a chamber to adsorb it onto the substrate surface, performing a first purge of the interior of the chamber with a purge gas, injecting the reducing agent into the chamber to reduce the adsorbed precursor compound, and performing a second purge of the interior of the chamber with a purge gas.

[0021] The method for forming a thin film may further include injecting a nitriding agent or an additional reducing agent into the chamber to form a nitride film.

[0022] The chamber can be an atomic layer deposition (ALD) chamber, a chemical vapor deposition (CVD) chamber, a plasma-enhanced atomic layer deposition (PEALD) chamber, or a plasma-enhanced chemical vapor deposition (PECVD) chamber.

[0023] The substrate carried into the chamber may be heated to 100 to 800°C.

[0024] The nitriding agent may be ammonia or the like.

[0025] The additional reducing agent may be hydrogen or the like.

[0026] The thin film may be an aluminum metal film, a copper metal film, a gold metal film, a molybdenum metal film, a silver metal film, a tungsten metal film, a platinum metal film, a tantalum metal film, a cobalt metal film, a ruthenium metal film, a titanium metal film, an aluminum nitride film, a copper nitride film, a gold nitride film, a molybdenum nitride film, a silver nitride film, a tungsten nitride film, a platinum nitride film, a tantalum nitride film, a cobalt nitride film, a ruthenium nitride film, or a titanium nitride film.

[0027]

[0028] The present invention also provides a semiconductor substrate manufactured by the above-described thin film formation method.

[0029] The thin film may be a multi-layer structure of two or three layers.

[0030]

[0031] Furthermore, the present invention provides a semiconductor device comprising the semiconductor substrate described above. [Effects of the Invention]

[0032] According to the present invention, by applying a predetermined reducing agent, a reduction effect can be simultaneously provided at a process temperature at which the precursor does not thermally decompose, and even when a thin film is formed on a highly integrated substrate or a substrate having a complex structure, a uniform thin film can be formed and impurities and film quality can be improved, thereby providing a method for forming a high-quality thin film.

[0033] Furthermore, the present invention has the effect of more effectively reducing process by-products that cause corrosion and deterioration of characteristics during thin film formation, and improving the crystallinity of the thin film by modifying the film quality, thereby improving the electrical characteristics of the thin film.Furthermore, the present invention has the effect of providing a thin film formation method using the same and a semiconductor substrate manufactured thereby. [Brief explanation of the drawings]

[0034] [Figure 1] 10 is a graph showing the results of analysis by Auger electron spectroscopy (AES) at each temperature according to Example 5 of the present invention.

[0035] [Figure 2] 1 is a graph showing X-ray diffraction (XRD) analysis results for each process temperature in Example 5 according to the present invention and Comparative Example 3. It is also a graph showing the content of impurities such as carbon, nitrogen, and oxygen in Example 2 and Comparative Example 1 according to the prior art.

[0036] [Figure 3] 1 is an XRD analysis graph of Example 6 according to the present invention and conventional Comparative Example 4. DETAILED DESCRIPTION OF THE INVENTION

[0037] The above-described thin film forming method and the semiconductor substrate produced thereby will be described in detail below.

[0038] In this description, the term "reducing agent", unless otherwise specified, refers to a substance capable of displacing the ligands of a precursor compound to provide a film quality.

[0039] In this description, unless otherwise specified, the term "modification" means that a substance other than the precursor and reactant actively interacts with the reaction surface to improve the film quality, such as reducing the resistivity, increasing the density, or reducing impurities, of the deposited thin film.

[0040] The inventors have confirmed that by using a specific reducing agent that can function as a reducing agent for a precursor compound adsorbed on the surface of a substrate brought into a chamber at a relatively low process temperature at which the precursor does not thermally decompose, it is possible to prevent the inflow of impurities while improving film quality such as electrical properties, dielectric properties, and thin film density, and as a result of extensive research into this, the present invention has been completed.

[0041]

[0042] The thin film can be provided as a precursor of one or more selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti, for example, and can provide a nitride film or a metal film. In this case, the effects to be achieved in the present invention can be sufficiently obtained.

[0043] Specific examples of the thin film include a tungsten film, a ruthenium film, a copper film, a rhodium film, a molybdenum nitride film, a tungsten nitride film, and a titanium nitride film.

[0044] The thin film may include the above film compositions alone or in selective areas, but may also include, but is not limited to, SiH, SiOH.

[0045] The thin film can be used in semiconductor devices as a commonly used diffusion barrier film or electrode film.

[0046] The thin film may be a laminated film of one or more materials selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti.

[0047]

[0048] The precursor compound used to form the thin film in the present invention may be a precursor compound used for metal wiring or diffusion prevention purposes.

[0049] The precursor compound may be, for example, a compound having a central metal atom (M) of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, or Ti and a ligand (L 1 , L 2 , L 3 , L 4 , L 5 , L 6 etc.) may have a structure bound thereto.

[0050] Specific examples of the precursor compound include a molecule having a central metal atom (M) of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, or Ti and one or more ligands consisting of C, N, O, H, or X (halogen), and the precursor has a vapor pressure of 0.01 mTorr to 100 Torr at 25°C, which can maximize the effect of being used as the reducing agent.

[0051] For example, when the central metal is divalent, L 1 and L 2 can attach to the central metal as a ligand, and if the central metal is hexavalent, L 1 , L 2 , L 3 , L 4 , L 5 , L 6 can stick to the central metal, and L 1 ~L 6 The ligands corresponding to may be the same or different from each other.

[0052] As an example, L 1 , L 2 , L 3 , L 4 , L 5 and L 6are -H or -R, which may be the same or different, and -R is C1 to C 10 Alkyl, C1-C 10 Alkenes or C1-C 10 and wherein L is an alkane of the formula 1 , L 2 , L 3 and L 4 The n number of L can be 2 to 6 depending on the oxidation value of the central metal.

[0053] For example, when the central metal is divalent, L 1 and L 2 can attach to the central metal as a ligand, and if the central metal is hexavalent, L 1 , L 2 , L 3 , L 4 , L 5 , L 6 can stick to the central metal, and L 1 ~L 6 The ligands corresponding to may be the same or different from each other.

[0054] As a specific example, L 1 , L 2 , L 3 , L 4 , L 5 and L 6 are -H, -OR or -NR2, which may be the same or different, and where -R is H, C1 to C 10 Alkyl, C1-C 10 Alkenes, C1-C 10 The alkane may be iPr or TBu, which has a suitable degree of reaction energy to be replaced by the reducing agent described below.

[0055] As a specific example, L 1 , L 2 , L 3 , L 4 , L 5 and L 6is -H or -X, which may be the same or different, and in this case, -X may be F, Cl, Br, or I, and in this case, has a degree of reaction energy suitable for being replaced by a reducing agent described below.

[0056] As a specific example, L 1 , L 2 , L 3 , L 4 , L 5 and L 6 L 1 , L 2 , L 3 and L 4 is -H or -R, which may be the same or different, and wherein -R is C1 to C 10 Alkyl, C1-C 10 Alkenes or C1-C 10 and may have a linear or cyclic structure, in which case it has a suitable degree of reaction energy to be displaced by the reducing agent described below.

[0057] As a specific example, L 1 , L 2 , L 3 , L 4 , L 5 and L 6 are -H, -OR or -NR2, which may be the same or different, and where -R is H, C1 to C 10 Alkyl, C1-C 10 Alkenes, C1-C 10 The alkane may be iPr or tBu, which has a suitable degree of reaction energy to be replaced by the reducing agent described below.

[0058] As a specific example, L 1 , L 2 , L 3 , L 4 , L 5 and L 6is -H or -X, which may be the same or different, and in this case, -X may be F, Cl, Br, or I, and in this case, has a degree of reaction energy suitable for being replaced by a reducing agent described below.

[0059]

[0060] Specifically, the precursor compound having molybdenum (Mo) as the central metal may be one or more compounds selected from compounds having structures represented by the following chemical formulas 1 and 2, and may contain a trimethylenemethane ligand and its derivatives, but the present invention is not limited thereto.

[0061] [Chemical formula 1]

[0062] [ka]

[0063] (In the above chemical formula 1, R1 to R5 are each independently selected from hydrogen, an amino group, a silyl group, an alkyl group having 1 to 8 carbon atoms, and an aryl group having 6 to 8 carbon atoms, and the case where R1 to R5 are simultaneously hydrogen atoms is not included.)

[0064] [Chemical formula 2]

[0065] [ka]

[0066] (In the above chemical formula 2, X is H; F; Cl; Br; I; NO; CN; amidinate; guanidinate; ethylenediamine; propylenediamine; -NR6R7; -OR8; R9Cp and linear and branched cyclic, saturated or unsaturated hydrocarbons substituted with one or more of carbon (C), nitrogen (N), oxygen (O), phosphorus (P), and sulfur (S), and R6, R7, R8, and R9 are each independently selected from hydrogen, an alkyl group having 1 to 12 carbon atoms, and an aryl group having 6 to 12 carbon atoms, and n is an integer of 0 to 2.)

[0067] The derivative of the trimethylenemethane ligand may include, for example, a structure having a tribenzylidenemethane ligand, a dibenzylidenemethane ligand, or the like.

[0068] Examples of precursor compounds with molybdenum (Mo) as the central metal include hexacarbonylmolybdenum (Mo(CO)6), bis(ethylbenzene)molybdenum ((Ethylbenzene)2Mo), tricarbonyl(2,6-diisopropylaniline)molybdenum ((2,6-diisopropylaniline)Mo(CO)3), carbonyl(1,4-diisopropyl-1,4-diazabutadiene)molybdenum ((1,4-diisopropyl-1,4-diazabutadiene)Mo(CO)), pentacarbonyl(dichloromethylphosphine)molybdenum (Mo(CO)5PCl2Me), and molybdenum acetate dimer. Dimer), bis(allyl)(ethylbenzene)molybdenum ((Ethylbenzene)Mo(allyl)2), dicarbonyl(allyl)(methylcyclopentadienyl)molybdenum (MeCpMo(CO)2(allyl)), dicarbonyl(allyl)(isopropylcyclopentadienyl)molybdenum (iPrCpMo(CO)2(allyl)), tris(tetramethylheptanedionato)molybdenum (Mo(thd)3), tris(ethyl methacrylate)(methylcyclopentadienyl)molybdenum ((MeCp)Mo(EMA)3), bis(methylcyclopentadienyl)(tert-butylimido)molybdenum ((tert-butylimido)Mo(MeCp)2), tetrakis(dimethylamido)molybdenum Molybdenum (TDMAMo), dihydridobis(cyclopentadienyl)molybdenum (Cp2MoH2), tetrakis(dithiocarbamate)molybdenum (Mo(Dithiocarbamate)4), chlorobis(tert-butylimido)(aminothiolate)molybdenum ((tert-butylimido)2MoCl(aminothiolate)), (aminothiolate)bis(tert-butylimido)(tert-butylthiol)molybdenum ((tert-butylimido)2Mo(tert-butylthiol)(aminothiolate)), bis(aminothiolate)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(aminothiolate)2),Bis(tert-butylthiol)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(tert-butylthiol)2), bis(tert-butylamine)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(tert-butylamine)2), (cyclopentadienylethyl methacrylate)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(CpEMA)), dioxobis(isopropylamidinato)molybdenum ( MoO2(iPr-amidinate)2), bis(isopropylamidinato)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(iPr-amidinate)2), bis(tert-butoxy)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(tert-butoxy)2), (N,N-dimethyldiethylenetriamine)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine)bis(tert-butylimido)molybdenum triamine), chloro(hydrazido)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(hydrazido)Cl), dioxobis(dithiocarbamate)molybdenum (MoO2(Dithiocarbamate)2), bis(tert-butylimido)(1,4-di-tert-butyl-1,4-diazabutadiene)molybdenum ((1,4-ditert-butyl-1,4-diazabutadiene)Mo(tert-butylimido)2), dichlorodioxomolybdenum (MoO2Cl2), etc.

[0069] Here, the dichlorodioxomolybdenum (MoO2Cl2), bis(ethylbenzene)molybdenum ((Ethylbenzene)2Mo), tricarbonyl(2,6-diisopropylaniline)molybdenum ((2,6-diisopropylaniline)Mo(CO)3), tricarbonyl(benzene)molybdenum ((benzene)Mo(CO)3), and tricarbonyl(1,4-diisopropyl-1,4-diazabutadiene)molybdenum ((1,4-diisopropyl-1,4-diazabutadiene)Mo(CO)3) may be compounds represented by the following chemical formulas 3-1 to 3-5, respectively.

[0070] [Chemical formula 3-1~3-5]

[0071] [ka]

[0072] Here, the pentacarbonyl(dichloromethylphosphine)molybdenum (Mo(CO)5PCl2Me), molybdenum acetate dimer, bis(allyl)(ethylbenzene)molybdenum ((Ethylbenzene)Mo(allyl)2), dicarbonyl(allyl)(methylcyclopentadienyl)molybdenum (MeCpMo(CO)2(allyl)), and dicarbonyl(allyl)(isopropylcyclopentadienyl)molybdenum (iPrCpMo(CO)2(allyl)) may be compounds represented by the following chemical formulas 3-6 to 3-10, respectively.

[0073] [Chemical formula 3-6~3-10]

[0074] [ka]

[0075] Here, the tris(tetramethylheptanedionato)molybdenum (Mo(thd)3), tris(ethyl methacrylate)(methylcyclopentadienyl)molybdenum ((MeCp)Mo(EMA)3), bis(methylcyclopentadienyl)(tert-butylimido)molybdenum ((tert-butylimido)Mo(MeCp)2), tetrakis(dimethylamido)molybdenum (TDMAMo), and dihydridobis(cyclopentadienyl)molybdenum (Cp2MoH2) may be compounds represented by the following chemical formulas 3-11 to 3-15, respectively.

[0076] [Chemical formula 3-11~3-15]

[0077] [ka]

[0078] Here, the tetrakis(dithiocarbamate)molybdenum (Mo(Dithiocarbamate)4), chlorobis(tert-butylimido)(aminothiolate)molybdenum ((tert-butylimido)2MoCl(aminothiolate)), (aminothiolate)bis(tert-butylimido)(tert-butylthiol)molybdenum ((tert-butylimido)2Mo(tert-butylthiol)(aminothiolate)), bis(aminothiolate)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(aminothiolate)2), and bis(tert-butylthiol)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(tert-butylthiol)2) may be compounds represented by the following chemical formulas 3-16 to 3-20, respectively.

[0079] [Chemical formula 3-16~3-20]

[0080] [ka]

[0081] Here, the bis(tert-butylamine)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(tert-butylamine)2), (cyclopentadienylethyl methacrylate)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(CpEMA)), dioxobis(isopropylamidinato)molybdenum (MoO2(iPr-amidinate)2), and bis(isopropylamidinato)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(iPr-amidinate)2) may be compounds represented by the following chemical formulas 3-20 to 3-24, respectively.

[0082] [Chemical formula 3-20~3-24]

[0083] [ka]

[0084] Here, the bis(tert-butoxy)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(tert-butoxy)2) and (N,N-dimethyldiethylenetriamine)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine)bis(tert-butylimido)molybdenum triamine), chloro(hydrazido)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(hydrazido)Cl), dioxobis(dithiocarbamate)molybdenum (MoO2(Dithiocarbamate)2), bis(tert-butylimido)(1,4-di-tert-butyl-1,4-diazabutadiene)molybdenum ((1,4-ditert-butyl-1,4-diazabutadiene)Mo(tert-butylimido)2), dichlorodioxomolybdenum (MoO2Cl2), bis(dimethylamido)bis(tert-butylimido)molybdenum ((tert-butylimido)2Mo(dimethylamide)2), and bis(methylbenzene)molybdenum ((Methylbenzene)2Mo) can be compounds represented by the following chemical formulas 3-25 to 3-31, respectively.

[0085] [Chemical formula 3-25~3-31]

[0086] [ka]

[0087] For example, the precursor compound can be used by mixing with a non-polar solvent, which has the advantage that the viscosity and vapor pressure of the precursor compound can be easily adjusted.

[0088]

[0089] The reducing agent of the present invention can reduce the activation energy of precursor compounds adsorbed on a substrate, effectively displacing ligands.

[0090] The substitution of the ligand may be performed on the entire substrate or a portion of the substrate on which the thin film is formed, using, for example, the reducing agent and, if necessary, a nitriding agent or an additional reducing agent, as described below.

[0091] The reducing agent is characterized by containing one or more selected from hydrogen iodide, hydrogen iodide water, hydrogen bromide, and hydrogen bromide water. In such a case, the reducing agent fully functions as a reducing agent at a relatively low process temperature, suppressing side reactions during thin film formation, reducing process by-products in the thin film, thereby suppressing corrosion and deterioration, and not only realizing film quality improvements such as improved crystallinity of the thin film, but also having the effect of significantly improving the film thickness uniformity of the thin film, even when the thin film is formed on a highly integrated substrate or a substrate having a complex structure.

[0092] Specifically, the reducing agent may be 3N to 15N hydrogen iodide alone, a gas mixture of 1 to 99% by weight of 3N to 15N hydrogen iodide and the balance of an inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 3N to 15N hydrogen iodide and the balance of water to make the total amount 100% by weight. In this case, if the inert gas is nitrogen, helium, or argon with a purity of 4N to 9N, the effect of reducing process by-products is significant, and the effect of improving the density and electrical properties of the thin film may be superior.

[0093] Preferably, the reducing agent is 5N to 6N hydrogen iodide alone, a gas mixture of 1 to 99% by weight of 5N to 6N hydrogen iodide and the balance of an inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 5N to 6N hydrogen iodide and the balance of water to make the total amount 100% by weight, where the inert gas can be nitrogen, helium, or argon with a purity of 4N to 9N. In this case, side reactions are suppressed during thin film formation, the thin film growth rate is adjusted, process by-products in the thin film are reduced, corrosion and deterioration are suppressed, and not only is film quality improved, such as improved crystallinity of the thin film, but the thickness uniformity of the thin film can be significantly improved, even when the thin film is formed on a highly integrated substrate or a substrate with a complex structure.

[0094]

[0095] The reducing agent is preferably 5N to 6N hydrogen iodide alone, a gas mixture of 1 to 99% by weight of 5N to 6N hydrogen iodide and the balance of an inert gas so that the total amount is 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 5N to 6N hydrogen iodide and the balance of water so that the total amount is 100% by weight, where the inert gas can be nitrogen, helium, or argon having a purity of 4N to 9N.

[0096] In such cases, by providing a sufficient reduction effect to the precursor compound adsorbed on the substrate at a relatively low process temperature at which the precursor does not thermally decompose, the film thickness uniformity of the thin film can be significantly improved even when the thin film is formed on a highly integrated substrate or a substrate having a complex structure. In addition, the adsorption of not only the thin film precursor but also the process by-products can be prevented, thereby effectively protecting the surface of the substrate, thereby reducing the reaction rate and effectively removing the process by-products.

[0097]

[0098] The reducing agent may preferably be a compound with a purity of 99.9% or more, a compound with a purity of 99.95% or more, or a compound with a purity of 99.99% or more. For reference, if a compound with a purity of less than 99% is used, impurities may remain in the thin film or may cause side reactions with the precursor or reactant, so it is preferable to use a substance with a purity of 99% or more whenever possible.

[0099]

[0100] The thin film may contain, for example, 100 ppm or less of halogen compounds. For reference, if an excessive amount of halogen remains, for example, when a nitriding agent described later is used under a temperature condition of 200 to 300°C, chlorides such as NH4Cl are generated and remain in the thin film, which is undesirable.

[0101] The thin film can be used for applications such as an etching stopper film or an electrode film, but is not limited to these.

[0102] In particular, a relatively rough thin film is formed and the growth rate of the formed thin film is significantly reduced, so that the uniformity of the thin film can be ensured even when applied to a substrate with a complex structure, making it possible to deposit a particularly thin film.Furthermore, it is possible to achieve the effect of improving the amount of O, Si, metals, metal oxides, and even carbon remaining as process by-products, which has been difficult to reduce in the past.

[0103]

[0104] A method for forming a thin film according to one embodiment of the present invention includes the steps of injecting a precursor compound into a chamber to adsorb it onto a substrate surface, and injecting a reducing agent into the chamber to form a deposited film. Here, when one or more of the aforementioned hydrogen iodide, hydrogen iodide water, hydrogen bromide, and hydrogen bromide water are used as the reducing agent, the reduction of the precursor adsorbed onto the substrate is effectively carried out at a relatively low process temperature at which the precursor does not thermally decompose, thereby appropriately reducing the growth rate of the thin film and significantly improving the uniformity of the thin film, even when the thin film is formed on a highly integrated substrate or a substrate having a complex structure.

[0105] The reducing agent and precursor compound can be delivered into the chamber by the VFC method, the DLI method, or the LDS method.

[0106] The ratio (mg / cycle) of the precursor compound to the reducing agent introduced into the chamber may be 1:1 to 1:20.

[0107] In the step of injecting the reducing agent onto the substrate surface, the feeding time (seconds) of the reducing agent onto the substrate surface per cycle is preferably 0.01 to 10 seconds, more preferably 0.02 to 8 seconds, even more preferably 0.04 to 6 seconds, and even more preferably 0.05 to 4 seconds. Within this range, there are advantages such as a low thin film growth rate, excellent step coverage, and cost-effectiveness.

[0108] In this description, the reducing agent feeding time is based on a flow rate of 0.1 to 8,000 mg / cycle for a chamber volume of 15 to 20 L, and more specifically, a flow rate of 10 to 5,000 mg / cycle for a chamber volume of 18 L.

[0109]

[0110] As a specific example, the thin film formation method may include the steps of injecting a precursor compound into a chamber and allowing it to be adsorbed onto the substrate surface, performing a first purge of the interior of the chamber with a purge gas, injecting the reducing agent into the chamber to reduce the adsorbed precursor compound, and performing a second purge of the interior of the chamber with a purge gas.

[0111] The entire process described above can be considered as a unit cycle, and the cycle can be repeated until a thin film having a desired thickness is obtained. When the reducing agent is added sequentially after the precursor compound in one cycle to improve film quality, the generated process by-products are effectively removed, the resistivity of the thin film is reduced, and the step coverage is significantly improved. In addition, the thickness uniformity of the thin film is improved, and film qualities such as electrical properties, dielectric properties, and thin film density are improved.

[0112] The chamber can be an ALD chamber, a CVD chamber, a PEALD chamber, or a PECVD chamber.

[0113] The substrate carried into the chamber may be heated to 100 to 800°C.

[0114] The reducing agent or precursor compound may be vaporized and injected followed by a plasma post-treatment step, which can reduce process by-products while improving the growth rate of the thin film.

[0115]

[0116] A method for forming a thin film according to another embodiment of the present invention includes the steps of injecting a precursor compound into a chamber to adsorb it onto a substrate surface, injecting a reducing agent into the chamber to form a deposited film, and injecting a nitriding agent or an additional reducing agent into the chamber to form a nitride film. In this case, the precursor adsorbed on the substrate is effectively reduced, and the growth rate of the thin film is appropriately reduced, thereby significantly improving film quality such as electrical properties and thin film density, even when a thin film is formed on a highly integrated substrate or a substrate having a complex structure.

[0117]

[0118] As a specific example, the thin film formation method may include the steps of injecting a precursor compound into a chamber to adsorb it onto the substrate surface, performing a first purge of the interior of the chamber with a purge gas, injecting the reducing agent into the chamber to reduce the adsorbed precursor compound, performing a second purge of the interior of the chamber with a purge gas, injecting a nitriding agent or an additional reducing agent into the chamber to form a thin film, and performing a third purge of the interior of the chamber with a purge gas.

[0119] The entire process described above can be considered as a unit cycle, and the cycle can be repeated until a thin film having a desired thickness is obtained. When the reducing agent is added sequentially after the precursor compound in one cycle to improve film quality, process by-products can be significantly reduced, step coverage can be significantly improved, and the crystallinity of the thin film can be increased, thereby reducing the resistivity of the thin film. Even when applied to semiconductor devices with a large aspect ratio, the uniformity of the thin film thickness can be significantly improved, ensuring the reliability of the semiconductor device and also improving film quality such as electrical characteristics and thin film density.

[0120] The chamber can be an ALD chamber, a CVD chamber, a PEALD chamber, or a PECVD chamber.

[0121] The substrate carried into the chamber may be heated to 100 to 800°C.

[0122] The nitriding agent may be nitrogen, ammonia, or the like.

[0123] The additional reducing agent may be hydrogen or the like.

[0124] In this description, the feeding time of the nitriding agent or additional reducing agent is based on a flow rate of 0.1 to 8,000 mg / cycle with a chamber volume of approximately 15 to 20 L, and more specifically, a flow rate of 10 to 5,000 mg / cycle with a chamber volume of approximately 18 L.

[0125]

[0126] In the step of purging the unadsorbed precursor compound, the amount of purge gas introduced into the ALD chamber is not particularly limited as long as it is an amount sufficient to remove the unadsorbed precursor compound, but for example, it may be 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times the volume of the precursor compound introduced into the ALD chamber. Within this range, the unadsorbed precursor compound can be sufficiently removed to form a uniform thin film and prevent deterioration of film quality. Here, the amounts of the purge gas and precursor compound introduced are each based on one cycle, and the volume of the precursor compound refers to the volume of vaporized precursor compound vapor.

[0127]

[0128] In addition, in the purge step performed immediately after the additional reducing agent supply step, the amount of purge gas introduced into the ALD chamber may be, for example, 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times the volume of the additional reducing agent introduced into the ALD chamber, and the desired effect can be sufficiently obtained within this range. Here, the amounts of the purge gas and the additional reducing agent introduced are each based on one cycle.

[0129]

[0130] The reducing agent, precursor compound, nitriding agent, or additional reducing agent can be delivered into the ALD chamber preferably by a vapor flow control (VFC) method, a direct liquid injection (DLI) method, or a liquid delivery system (LDS) method, and more preferably by a VFC method.

[0131] The substrate loaded into the chamber may be heated to, for example, 100 to 800°C, specifically, 300 to 600°C, and the reducing agent or precursor compound may be injected onto the substrate either unheated or heated. Depending on the deposition efficiency, the reducing agent or precursor compound may be injected unheated and then the heating conditions may be adjusted during the deposition process. For example, the reducing agent or precursor compound may be injected onto the substrate at a temperature of 50 to 400°C for 1 to 20 seconds.

[0132]

[0133] The ratio of the amounts (mg / cycle) of the precursor compound and the reducing agent introduced into the chamber may be preferably 1:1 to 1:20, more preferably 1:2 to 1:15, even more preferably 1:2 to 1:12, and even more preferably 1:2.5 to 1:10. Within this range, the effect of improving step coverage and the effect of reducing process by-products are significant.

[0134]

[0135] The thin film formation method can be carried out at a deposition temperature in the range of, for example, 100 to 800°C, preferably 300 to 600°C, more preferably 300 to 500°C, and even more preferably 300 to 400°C. Within this range, ALD process characteristics can be achieved and a thin film with excellent film quality can be grown.

[0136] The thin film formation method can be carried out, for example, at a deposition pressure in the range of 0.01 to 20 Torr, preferably at a deposition pressure in the range of 0.1 to 20 Torr, more preferably at a deposition pressure in the range of 0.1 to 10 Torr, and most preferably at a deposition pressure in the range of 0.3 to 7 Torr. Within this range, a thin film with a uniform thickness can be obtained.

[0137] In this description, the deposition temperature and deposition pressure may be measured as the temperature and pressure formed in the deposition chamber, or may be measured as the temperature and pressure applied to the substrate in the deposition chamber.

[0138] The thin film formation method may preferably include a step of raising the temperature in the chamber to a deposition temperature before introducing the precursor compound into the chamber, and / or a step of injecting an inert gas into the chamber to purge the chamber before introducing the precursor compound into the chamber.

[0139]

[0140] In the thin film formation method, the strength (c / s) of residual halogen in the thin film, based on a film thickness of 100 Å, as measured by secondary ion mass spectrometry (SIMS), is preferably 100,000 or less, more preferably 70,000 or less, even more preferably 50,000 or less, and even more preferably 10,000 or less, and in a preferred embodiment, it is 5,000 or less, more preferably 10 to 4,000, and even more preferably 10 to 3,000.Within such a range, there is an excellent effect of preventing corrosion and deterioration.

[0141] In this description, the purge flow rate is preferably 1,000 to 50,000 sccm (standard cubic centimeters per minute), more preferably 2,000 to 30,000 sccm, and even more preferably 2,500 to 15,000 sccm. Within this range, the thin film growth rate per cycle is appropriately controlled, and deposition is performed as or close to an atomic monolayer, which is advantageous in terms of film quality.

[0142]

[0143] Furthermore, the present invention may include a thin-film production apparatus capable of carrying out the thin-film production method, the thin-film production apparatus including an ALD chamber, a first vaporizer that vaporizes a precursor compound, a first delivery means that delivers the vaporized precursor compound into the ALD chamber, a second vaporizer that vaporizes a reducing agent, a second delivery means that delivers the vaporized reducing agent into the ALD chamber, and a third delivery means that delivers a nitriding agent or an additional reducing agent into the ALD chamber. Here, the vaporizer and delivery means are not particularly limited as long as they are vaporizers and delivery means that are commonly used in the technical field to which the present invention pertains.

[0144] To explain the thin film formation method in detail, first, a substrate on which a thin film is to be formed is placed in a deposition chamber capable of depositing atomic layers.

[0145] The substrate may include a semiconductor substrate such as a silicon substrate, silicon oxide, or the like.

[0146] The substrate may further have a conductive or insulating layer formed thereon.

[0147] To deposit a thin film on a substrate placed in the deposition chamber, the above-mentioned reducing agent, precursor compound, or a mixture thereof with a non-polar solvent, etc., are prepared.

[0148] Then, the prepared precursor compound or a mixture of the precursor compound and a non-polar solvent (hereinafter referred to as "thin film forming composition") is injected into a vaporizer, converted into a vapor phase, and transported to a deposition chamber to be adsorbed onto a substrate, and the unadsorbed precursor compound or the mixture of the precursor compound and a non-polar solvent is purged.

[0149] The non-polar solvent may be at least one selected from the group consisting of alkanes and cycloalkanes. In this case, the non-polar solvent has the advantage of improving step coverage even when the deposition temperature is elevated during thin film formation, while containing an organic solvent that has low reactivity and solubility and allows easy moisture management.

[0150] In a more preferred example, the non-polar solvent is a C1 to C 10 Alkanes of C3 to C 10 and preferably C3 to C 10 In this case, the advantage is that the reactivity and solubility are low, and moisture can be easily controlled.

[0151] In this description, C1, C3, etc. refer to the number of carbon atoms.

[0152] The cycloalkane is preferably a C3 to C 10 Among the monocycloalkanes, cyclopentane is liquid at room temperature and has the highest vapor pressure, so it is suitable for the vapor deposition process, but is not limited thereto.

[0153] The non-polar solvent has, for example, a solubility in water (25°C) of 200 mg / L or less, preferably 50 to 400 mg / L, and more preferably 135 to 175 mg / L. Within this range, the non-polar solvent has the advantages of low reactivity with the precursor compound and easy water management.

[0154] In this description, the solubility is not particularly limited as long as it is measured by a measurement method or standard commonly used in the technical field to which the present invention pertains, and as an example, a saturated solution can be measured by high performance liquid chromatography (HPLC).

[0155] The non-polar solvent preferably comprises 5 to 95% by weight, more preferably 10 to 90% by weight, even more preferably 40 to 90% by weight, and most preferably 70 to 90% by weight, based on the total weight of the precursor compound and the non-polar solvent.

[0156] If the content of the non-polar solvent exceeds the upper limit, impurities are generated, increasing the number of impurities in the resistor and the thin film. If the content of the organic solvent is below the lower limit, the effect of improving step coverage and the effect of reducing impurities such as chlorine (Cl) ions by adding the solvent cannot be fully achieved.

[0157]

[0158] Next, the prepared reducing agent is injected into the vaporizer, converted into a vapor phase, and delivered to the deposition chamber for adsorption, and the unadsorbed reducing agent is purged.

[0159] In this description, the reducing agent and precursor compound (thin film forming composition) can be delivered to the deposition chamber by the following methods: For example, a method of delivering a vaporized gas using a mass flow controller (MFC) (Vapor Flow Control; VFC) or a method of delivering a liquid using a liquid mass flow controller (LMFC) (Liquid Delivery System; LDS) may be used, and preferably, a VFC method is used.

[0160] In this case, the carrier gas or dilution gas for transporting the reducing agent, precursor compound, etc. onto the substrate may be one or a mixture of two or more gases selected from the group consisting of argon (Ar), nitrogen (N2), and helium (He), but is not limited thereto.

[0161] In this description, the purge gas may be, for example, an inert gas, and preferably, the carrier gas or dilution gas.

[0162]

[0163] Next, a nitriding agent or an additional reducing agent is supplied as needed. The nitriding agent or additional reducing agent is not particularly limited as long as it is an additional reducing agent commonly used in the technical field to which the present invention pertains, and preferably includes a nitriding agent such as nitrogen gas (N), hydrazine gas (NH), or a mixture of nitrogen gas and hydrogen gas, and an additional reducing agent such as hydrogen gas (H).

[0164] The nitriding agent reacts with the precursor compound adsorbed on the substrate to form a nitride film.

[0165] The additional reducing agent reacts with the precursor compound adsorbed on the substrate to form a metal film.

[0166] Next, the remaining unreacted nitriding agent or additional reducing agent is purged using an inert gas, which simultaneously removes not only the excess nitriding agent or additional reducing agent but also the by-products that are produced.

[0167]

[0168] As described above, the thin film formation method, for example, includes a unit cycle including the steps of adsorbing a precursor compound / thin film forming composition onto a substrate, purging any unadsorbed precursor compound, adsorbing a reducing agent onto the substrate, purging any unadsorbed reducing agent, supplying a nitriding agent or additional reducing agent as needed, and purging any remaining nitriding agent or additional reducing agent as needed, and the unit cycle can be repeated to form a thin film of a desired thickness.

[0169] The unit cycle can be repeated, for example, 1 to 99,999 times, preferably 10 to 1,000 times, more preferably 50 to 5,000 times, and even more preferably 100 to 2,000 times. Within this range, the desired thin film properties are effectively exhibited.

[0170]

[0171] The present invention also provides a semiconductor substrate, characterized in that the semiconductor substrate is manufactured by the thin film formation method described above. In such a case, the thin film has excellent uniformity in film thickness, and has excellent density and electrical properties.

[0172]

[0173] The thin film thus produced preferably has a thickness of 30 nm or less, a resistivity of 5 to 2,000 μΩ·cm when the thin film is 10 nm thick, a halogen content of 10,000 ppm or less, and a step coverage of 90% or more. Within these ranges, the thin film has excellent performance as a diffusion barrier film and exhibits the effect of reducing corrosion of metal wiring materials, but is not limited thereto.

[0174] The thin film may have a thickness of, for example, 0.1 to 30 nm, preferably 1 to 20 nm, and more preferably 2 to 10 nm, and within this range, the thin film has the effect of having excellent thin film properties.

[0175] For example, the thin film may have a resistivity of 0.1 to 400 μΩ·cm, preferably 15 to 300 μΩ·cm, and more preferably 20 to 290 μΩ·cm, based on a film thickness of 10 nm. Within this range, the thin film has excellent thin film properties.

[0176] The thin film may have a halogen content of preferably 10,000 ppm or less, or 1 to 9,000 ppm, more preferably 5 to 8,500 ppm, and even more preferably 100 to 1,000 ppm. Within this range, the thin film has excellent thin film properties while reducing the thin film growth rate. Here, examples of halogens remaining in the thin film include Cl2, Cl, and Cl. - The lower the amount of residual halogen in the thin film, the better the film quality, which is preferable.

[0177] The thin film has a step coverage of, for example, 90% or more, preferably 92% or more, and more preferably 95% or more. Within this range, even thin films with complex structures can be easily deposited on a substrate, and this has the advantage of making them applicable to next-generation semiconductor devices.

[0178] The thin film thus produced preferably has a thickness of 20 nm or less, a carbon, nitrogen, and halogen content of 10,000 ppm or less based on a 10 nm thickness of the thin film, and a step coverage of 90% or more. Within these ranges, the thin film has the effect of exhibiting excellent performance as a dielectric film or a blocking film, but is not limited thereto.

[0179]

[0180] Below, preferred examples and drawings are presented to help understand the present invention better. However, the following examples and drawings are merely illustrative of the present invention, and it will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the present invention and the technical idea thereof. It goes without saying that such changes and modifications are also included within the scope of the appended claims.

[0181]

[0182] [Example]

[0183] Example 1

[0184] The ALD process was carried out using 5N HI as a reducing agent and a BTBMMo precursor having the following chemical formula as a precursor compound.

[0185] [Chemical formula]

[0186] [ka]

[0187] First, the prepared precursor compound was placed in a separate canister and supplied to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The BTBMMo precursor vaporized in the vaporizer was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. The pressure inside the reaction chamber was controlled at 2.5 Torr.

[0188] Next, the prepared reducing agent was placed in a canister and supplied to the chamber at room temperature using a mass flow controller (MFC) at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure inside the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0189] The thickness of the fabricated thin film (MoN metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The thickness was measured by dividing the measured value by the number of cycles, and the calculated thickness was 10 nm. The thin film's components were analyzed using AES and SIMS. Furthermore, the sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity.

[0190]

[0191] Example 2

[0192] The ALD process was carried out using 5N HI and NH3 as reducing agents and a BTBMMo precursor with the following chemical formula as a precursor compound.

[0193] [Chemical formula]

[0194] [ka]

[0195] First, the prepared precursor compound was placed in a separate canister and supplied to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The BTBMMo precursor vaporized in the vaporizer was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. The pressure inside the reaction chamber was controlled at 2.5 Torr.

[0196] Next, the prepared HI reducing agent was placed in a canister and supplied to the chamber at a flow rate of 1000 sccm using a mass flow controller (MFC) at room temperature. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. Furthermore, NH3 reducing agent was supplied to the chamber at a flow rate of 1000 sccm, and then argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0197] The thickness of the fabricated thin film (MoN metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The thickness was then divided by the number of cycles to calculate the thickness of the thin film deposited per cycle, which was 10 nm. The thin film's components were analyzed using AES and SIMS. Furthermore, the sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity.

[0198]

[0199] Example 3

[0200] The ALD process was carried out using 5N HI as a reducing agent and a BTBTBMo precursor of the following chemical formula as a precursor compound.

[0201] [Chemical formula]

[0202] [ka]

[0203] First, the prepared precursor compound was placed in a separate canister and supplied to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The BTBTBMo precursor vaporized in the vaporizer was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. The pressure inside the reaction chamber was controlled at 2.5 Torr.

[0204] Next, the prepared reducing agent was placed in a canister and supplied to the chamber at room temperature using a mass flow controller (MFC) at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure inside the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0205] The thickness of the fabricated thin film (MoN metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The thickness was then divided by the number of cycles to calculate the thickness of the thin film deposited per cycle, which was 10 nm. The thin film's components were analyzed using AES and SIMS. Furthermore, the sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity.

[0206]

[0207] Example 4

[0208] The ALD process was carried out using 5N HI and NH3 as reducing agents and a BTBTBMo precursor with the following chemical formula as a precursor compound.

[0209] [Chemical formula]

[0210] [ka]

[0211] First, the prepared precursor compound was placed in a separate canister and supplied to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The BTBTBMo precursor vaporized in the vaporizer was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. The pressure inside the reaction chamber was controlled at 2.5 Torr.

[0212] Next, the prepared HI reducing agent was placed in a canister and supplied to the chamber at a flow rate of 1000 sccm using a mass flow controller (MFC) at room temperature. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. Furthermore, NH3 reducing agent was supplied to the chamber at a flow rate of 1000 sccm, and then argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0213] The thickness of the fabricated thin film (MoN metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The thickness was then divided by the number of cycles to calculate the thickness of the thin film deposited per cycle, which was 10 nm. The thin film's components were analyzed using AES and SIMS. Furthermore, the sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity.

[0214]

[0215] Example 5

[0216] The ALD process was carried out using 5N HI as the reducing agent and Mo(CO)6 precursor of the following chemical formula as the precursor compound.

[0217] [Chemical formula]

[0218] [ka]

[0219] First, the prepared precursor compound was placed in a separate canister and heated to 50°C. While Ar gas was flowing at 50 sccm as a carrier gas, the Mo(CO) precursor was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the reaction chamber was controlled at 2.5 Torr.

[0220] Next, the prepared reducing agent was placed in a canister and supplied to the chamber at room temperature using a mass flow controller (MFC) at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 375°C, and this process was repeated 50 to 200 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0221] The fabricated thin film (Mo metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The film thickness was measured by dividing the measured film thickness by the number of cycles, resulting in a film thickness of 10 nm deposited per cycle. The sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity. The crystallinity of the Mo thin film was confirmed by XRD analysis.

[0222]

[0223] Example 6

[0224] The ALD process was carried out using 5N HI as a reducing agent and Mo(tol)2 precursor of the following chemical formula as a precursor compound.

[0225] [Chemical formula]

[0226] [ka]

[0227] First, the prepared precursor compound was placed in a separate canister and heated to 130°C. While Ar gas was flowing at 50 sccm as a carrier gas, the Mo(tol) precursor was introduced into the deposition chamber for 10 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the reaction chamber was controlled at 2.5 Torr.

[0228] Next, the prepared reducing agent was placed in a canister and supplied to the chamber at room temperature using a mass flow controller (MFC) at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 250°C, and this process was repeated 30 to 300 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0229] The film thickness of the produced thin film (Mo metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light, and the film thickness was divided by the number of cycles to calculate the film thickness deposited per cycle, which was 10 nm.The sheet resistance was measured using the four-probe measurement method, and the measured film thickness was used to calculate the resistivity value.

[0230]

[0231] [Comparative Example]

[0232] Comparative Example 1

[0233] The ALD process was carried out using NH3 as a reducing agent and a BTBMMo precursor having the following chemical formula as a precursor compound.

[0234] [Chemical formula]

[0235] [ka]

[0236] First, the prepared precursor compound was placed in a separate canister and fed to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The BTBMMo precursor vaporized in the vaporizer was introduced into the deposition chamber for 3 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. The pressure inside the reaction chamber was controlled at 2.5 Torr.

[0237] Next, the prepared reducing agent NH3 was supplied into the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0238] The thickness of the fabricated thin film (MoN metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The thickness was then divided by the number of cycles to calculate the thickness of the thin film deposited per cycle, which was 10 nm. The thin film's components were analyzed using AES and SIMS. Furthermore, the sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity.

[0239]

[0240] Comparative Example 2

[0241] The ALD deposition process was carried out using NH3 as a reducing agent and BTBTBMo precursor with the following formula as a precursor compound.

[0242] [Chemical formula]

[0243] [ka]

[0244] First, the prepared precursor compound was placed in a separate canister and supplied to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The BTBTBMo precursor vaporized in the vaporizer was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. The pressure inside the reaction chamber was controlled at 2.5 Torr.

[0245] Next, the prepared reducing agent, NH3, was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0246] The thickness of the fabricated thin film (MoN metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The thickness was then divided by the number of cycles to calculate the thickness of the thin film deposited per cycle, which was 10 nm. The thin film's components were analyzed using AES and SIMS. Furthermore, the sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity.

[0247]

[0248] Comparative Example 3

[0249] The ALD process was carried out using NH3 as the reducing agent and Mo(CO)6 precursor of the following chemical formula as the precursor compound.

[0250] [Chemical formula]

[0251] [ka]

[0252] First, the prepared precursor compound was placed in a separate canister and heated to 50°C. While Ar gas was flowing at 50 sccm as a carrier gas, the Mo(CO) precursor was introduced into the deposition chamber for 3 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the reaction chamber was controlled at 2.5 Torr.

[0253] Next, the prepared reducing agent NH3 was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 375°C, and this process was repeated 50 to 200 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0254] The fabricated thin film (Mo metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light. The film thickness was measured by dividing the measured film thickness by the number of cycles, resulting in a film thickness of 10 nm deposited per cycle. The sheet resistance was measured using a four-probe measurement method, and the measured film thickness was used to calculate the resistivity. The crystallinity of the Mo thin film was confirmed by XRD analysis.

[0255]

[0256] Comparative Example 4

[0257] The ALD process was carried out using NH3 as the reducing agent and Mo(tol)2 precursor of the following chemical formula as the precursor compound.

[0258] [Chemical formula]

[0259] [ka]

[0260] First, the prepared precursor compound was placed in a separate canister and heated to 130°C. While Ar gas was flowing at 50 sccm as a carrier gas, the Mo(tol) precursor was introduced into the deposition chamber for 10 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the reaction chamber was controlled at 2.5 Torr.

[0261] Next, the prepared reducing agent NH3 was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vapor phase in the vaporizer, was introduced into the deposition chamber containing the substrate for 2 seconds, after which argon gas was supplied at 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 250°C and 300°C, respectively, and this process was repeated 30 to 300 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0262] The film thickness of the produced thin film (Mo metal film) was measured using an ellipsometer, a device that can measure optical properties such as film thickness and refractive index using the polarization characteristics of light, and the film thickness was divided by the number of cycles to calculate the film thickness deposited per cycle, which was 10 nm.The sheet resistance was measured using the four-probe measurement method, and the measured film thickness was used to calculate the resistivity value.

[0263]

[0264] [Test example]

[0265] For each of the obtained thin films of Examples 1 to 6 and Comparative Examples 1 to 4, the impurity content, the type and content of elements constituting the surface of the material, the deposition rate, the crystal structure, the orientation, etc. were confirmed by the following methods.

[0266] *Analysis of carbon impurities using secondary ion mass spectrometry (SIMS): The ion sputter was driven into the thin film in the axial direction, and when the sputtering process time reached 50 seconds, which is considered to be the time when there is little contamination in the surface layer of the substrate, the carbon impurity counts were taken into consideration and the carbon impurity value was confirmed from the SIMS graph.

[0267] *Auger electron spectroscopy (AES): A focused electron beam is irradiated onto the surface of a material, and the energy of the emitted Auger electrons is measured to analyze the type and content of elements that make up the surface of the material.

[0268] *Measurement of deposition rate (GPC: Growth Per Cycle, growth amount per cycle): The deposition rate (GPC) was measured by the following method for each of the obtained thin films of Examples 1 to 6 and Comparative Examples 1 to 4. Specifically, an ellipsometer was used to measure the deposition rate of a thin film with a thickness of 3 to 30 nm, and the unit was Å / cycle.

[0269] * Grazing incidence X-ray diffraction method (incident angle (θ) = 3°): To confirm information such as crystal structure and orientation, a diffraction analysis of the surface was performed using Cu-Kα X-rays.

[0270] [Table 1]

[0271] As shown in Table 1 above, it was confirmed that the amount of C impurities generated when using an NH3 reducing agent alone can be rapidly reduced by utilizing the process using the HI reducing agent alone or the process using the HI reducing agent and NH3 together according to the present invention. Furthermore, as is clear from Examples 1 and 2, the AES analysis results confirmed that the C impurities were reduced to 0% during thin film formation, and the SIMS analysis results confirmed that the number of detected C ions was reduced by 91% or more.

[0272] Furthermore, the film density increased from 6.0 to 6.8, indicating that a MoN film of extremely high quality was formed.

[0273] [Table 2]

[0274] As shown in Table 2 above, by utilizing the process of using the HI reducing agent alone or the process of using the HI reducing agent and NH3 in combination according to the present invention, the resistivity of the formed thin film was rapidly reduced compared to when the NH3 reducing agent was used alone. Furthermore, it was shown that the C impurity was most effectively reduced when the HI reducing agent was used alone, in the order of Comparative Example 2 > Example 4 > Example 3.

[0275] [Table 3]

[0276] As shown in Table 3 above, when the HI reducing agent was used according to the present invention, the resistivity of the thin film formed was significantly reduced and the deposition rate was increased by more than three times compared to when only the NH3 reducing agent was used. In particular, XRD analysis was performed at each process temperature, and the results are shown in Figure 2 below. Figure 2 is a graph of XRD analysis at each process temperature for Example 5 of the present invention and Comparative Example 3.

[0277] As is clear from FIG. 2 below, in Example 5, a pure Mo metal thin film was formed.

[0278] Furthermore, the results of AES analysis at each temperature in Example 5 are shown in FIG.

[0279] FIG. 1 is a graph showing the results of AES analysis at each temperature in Example 5 of the present invention. As is clear from FIG. 1 below, the changes in the types and contents of constituent elements at each process temperature were confirmed.

[0280] [Table 4]

[0281] As shown in Table 4 above, when the HI reducing agent was used according to the present invention, the resistivity of the thin film formed was significantly reduced and the deposition rate was more than doubled compared to when only the NH3 reducing agent was used. In particular, XRD analysis was performed, and the results are shown in Figure 3 below. Figure 3 is an XRD analysis graph of Example 6 of the present invention and Comparative Example 4.

[0282] As is clear from FIG. 3 below, in Example 6, a partially pure Mo metal thin film was formed.

[0283]

[0284] In conclusion, by applying a specific reducing agent, it was confirmed that the uniformity of the thin film thickness can be significantly improved, even when forming a thin film on a highly integrated substrate or a substrate with a complex structure, and that the film quality is effectively improved through the reduction of impurities and the improvement of the thin film density and resistivity.

Claims

1. injecting a precursor compound into the chamber and allowing it to adsorb onto the substrate surface; injecting a reducing agent into the chamber to form a deposited film; Including, The thin film forming method, wherein the reducing agent is at least one selected from the group consisting of hydrogen iodide, hydrogen iodide water, hydrogen bromide and hydrogen bromide water.

2. 2. The thin film formation method according to claim 1, wherein the reducing agent is 3N to 15N hydrogen iodide alone, a gas mixture of 1 to 99% by weight of 3N to 15N hydrogen iodide and the balance of an inert gas so that the total amount is 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 3N to 15N hydrogen iodide and the balance of water so that the total amount is 100% by weight, wherein the inert gas is nitrogen, helium, or argon having a purity of 4N to 9N.

3. 2. The thin film forming method according to claim 1, wherein the thin film is a laminated film of one or more elements selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti.

4. 2. The method of claim 1, wherein the thin film is formed on the entire substrate or a part of the substrate, the nitride film, the metal film, or a selective thin film thereof.

5. 2. The thin film formation method according to claim 1, wherein the precursor compound is a molecule composed of one or more elements selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti, and is a compound having a vapor pressure at 25°C of more than 0.01 mTorr and not more than 100 Torr.

6. injecting a precursor compound into the chamber and allowing it to adsorb onto the substrate surface; a step of first purging the interior of the chamber with a purge gas; injecting said reducing agent into said chamber to reduce the adsorbed precursor compound; a step of second purging the interior of the chamber with a purge gas; The thin film forming method according to claim 1 , comprising:

7. 10. The method of claim 1, further comprising the step of injecting a nitriding agent or an additional reducing agent into the chamber to form a nitride film.

8. 10. The method of claim 1, wherein the chamber is an atomic layer deposition (ALD) chamber, a chemical vapor deposition (CVD) chamber, a plasma-enhanced atomic layer deposition (PEALD) chamber, or a plasma-enhanced chemical vapor deposition (PECVD) chamber.

9. 2. The thin film forming method according to claim 1, wherein the substrate carried into the chamber is heated to 100 to 800°C.

10. 2. The thin film forming method according to claim 1, wherein the thin film is an aluminum metal film, a copper metal film, a gold metal film, a molybdenum metal film, a silver metal film, a tungsten metal film, a platinum metal film, a tantalum metal film, a cobalt metal film, a ruthenium metal film, a titanium metal film, an aluminum nitride film, a copper nitride film, a gold nitride film, a molybdenum nitride film, a silver nitride film, a tungsten nitride film, a platinum nitride film, a tantalum nitride film, a cobalt nitride film, a ruthenium nitride film, or a titanium nitride film.

11. A semiconductor substrate manufactured by the thin film forming method according to any one of claims 1 to 10.

12. The semiconductor substrate according to claim 11, wherein the thin film has a multi-layer structure of two or three layers.

13. A semiconductor device comprising the semiconductor substrate of claim 11.

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