Thin film forming method, semiconductor substrate manufactured by method, and semiconductor device

Abstract

The present invention relates to a thin film forming method, a semiconductor substrate manufactured by the method, and a semiconductor device, which can greatly improve the thickness uniformity of a thin film even when the thin film is formed on a highly integrated substrate or a substrate having a complicated structure by using a predetermined reducing agent, and can improve the reliability of the thin film. And the method has the effect of effectively improving the film quality by reducing impurities and improving the density and resistivity of the film.

Description

Technical Field

[0001] The present invention relates to a thin film forming method, a semiconductor substrate manufactured by the method, and a semiconductor device. More specifically, the present invention relates to a thin film forming method, a semiconductor substrate manufactured by the method, and a semiconductor device. By adopting a prescribed reducing agent, a reducing effect is provided at a relatively low process temperature at which a precursor does not undergo thermal decomposition. Thus, even when a thin film is formed on a highly integrated substrate or a substrate having a complex structure, the thickness uniformity of the thin film can be greatly improved, impurities can be significantly reduced, and the film quality can be improved. Background Art

[0002] With the demand for higher performance and higher integration of semiconductor devices, electrode materials or diffusion barrier materials with lower resistivity are needed.

[0003] This material is provided in the form of a thin film through an atomic layer deposition (ALD) process, and the reduction process used to form this film requires the use of extremely strong reducing agents or high heat energy.

[0004] However, strong reducing agents such as hydrazine (N2H4) are highly toxic and dangerous, and therefore require careful handling. When high heat energy is applied, the precursor compound will undergo thermal decomposition, which may cause a decrease in step coverage or the appearance of voids or seams on highly integrated or complex substrates with high aspect ratios.

[0005] In addition, impurities (C, Cl - 、F - etc.) to cause contamination and also destroy the crystal arrangement, thereby reducing the density of the formed film, so the conductivity suppression problem caused by low density may occur.

[0006] Therefore, there is a need to develop a thin film forming method that can form a uniform thin film having a complex structure, has a low residual amount of impurities, and significantly improves the thickness uniformity of the thin film, as well as a semiconductor substrate manufactured using the method.

[0007] Prior art literature

[0008] Patent document: Korean Patent Publication No. 2019-0141071 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] In order to solve the problems of the prior art as described above, the object of the present invention is to provide a thin film forming method and a semiconductor substrate manufactured using the method, which effectively improves the thin film and deposition characteristics, such as reducing impurities and improving resistivity, by adopting a prescribed reducing agent, so that even when a thin film is formed on a substrate with a complex structure, a high-quality thin film with uniform thickness can be formed.

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

[0012] The above-mentioned and other objects of the present invention can be achieved by the present invention described below.

[0013] Means used to solve problems

[0014] To achieve the above objectives, the present invention provides a thin film forming method, which is characterized by comprising: a step of injecting a precursor compound into a chamber so that it is adsorbed on the surface of a substrate; and a step of injecting a reducing agent into the chamber to form a deposited film.

[0015] The reducing agent is one or more selected from the group consisting of hydrogen iodide, an aqueous hydrogen iodide solution, hydrogen bromide, and an aqueous hydrogen bromide solution.

[0016] The reducing agent may be pure 3N to 15N hydrogen iodide (HI), or a gas mixture of 1 wt% to 99 wt% of 3N to 15N hydrogen iodide (HI) and an inert gas with the remainder being 100 wt%; or an aqueous solution mixture of 0.5 wt% to 70 wt% of 3N to 15N hydrogen iodide (HI) and water with the remainder being 100 wt%, wherein the inert gas is nitrogen, helium, or argon with a purity of 4N to 9N.

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

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

[0019] The precursor compound may be a molecule consisting of one or more selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru and Ti, and the vapor pressure of the compound at 25° C. is greater than 0.01 mTorr and less than or equal to 100 Torr.

[0020] The thin film forming method may include: a step of injecting a precursor compound into a chamber so that it is adsorbed on the surface of a substrate; a step of performing a first purge of the interior of the chamber using a purge gas; a step of injecting the aforementioned reducing agent into the chamber to reduce the adsorbed precursor compound; and a step of performing a second purge of the interior of the chamber using a purge gas.

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

[0022] The chamber may 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 loaded in the chamber may be heated to 100° C. 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 can 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, etc.

[0027] Furthermore, the present invention provides a semiconductor substrate characterized by being manufactured using the above-mentioned thin film forming method.

[0028] The film may be a multilayer structure of two or three layers.

[0029] Furthermore, the present invention provides a semiconductor device, characterized by including the aforementioned semiconductor substrate.

[0030] Effects of the Invention

[0031] According to the present invention, the following effects are achieved: a thin film forming method is provided, which, by adopting a prescribed reducing agent, can simultaneously provide a reducing effect at a process temperature at which the precursor does not undergo thermal decomposition. Therefore, even when a thin film is formed on a highly integrated substrate or a substrate having a complex structure, a uniform thin film is formed, and impurities and film quality are improved, thereby forming a high-quality thin film.

[0032] Furthermore, the present invention more effectively reduces process byproducts that can cause corrosion or property degradation during thin film formation, improves film quality, and enhances film crystallinity, thereby improving thin film electrical properties. Furthermore, the present invention provides a thin film formation method utilizing the present invention and a semiconductor substrate manufactured using the method. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 1 is a graph showing the results of Auger Electron Spectroscopy (AES) analysis at different temperatures according to Example 5 of the present invention.

[0034] Figure 2 It is an X-ray diffraction (XRD) analysis diagram of different process temperatures according to Example 5 of the present invention and Comparative Example 3 belonging to the prior art, or a diagram confirming the impurity contents of carbon, nitrogen, oxygen, etc. in Example 2 and Comparative Example 1 according to the prior art.

[0035] Figure 3 3 is an XRD analysis diagram between Example 6 according to the present invention and Comparative Example 4 according to the prior art. DETAILED DESCRIPTION

[0036] Hereinafter, the thin film forming method of this specification and the semiconductor substrate manufactured by the method will be described in detail.

[0037] In this specification, unless otherwise specifically defined, the term "reducing agent" refers to a substance capable of improving film quality by replacing a ligand of a precursor compound.

[0038] In this specification, unless otherwise specifically defined, the term "modification" means that substances other than precursors and reactive substances actively interact on the reaction surface to improve film quality, such as reducing the resistivity of the deposited film, increasing the density, reducing impurities, etc.

[0039] The inventors have confirmed that using a specified reducing agent that can act as a reducing agent at a relatively low process temperature (a temperature at which the precursor is not thermally decomposed) for the precursor compound adsorbed on the surface of the substrate loaded inside the chamber can prevent and prevent the influx of impurities while improving the film quality such as electrical properties, dielectric properties, and thin film density. The inventors have devoted themselves to related research and ultimately completed the present invention.

[0040] As an example, the thin film can be provided by one or more precursors selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru and Ti, and a nitride film or a metal film can be provided. In this case, the effect to be achieved by the present invention can be fully obtained.

[0041] As a specific example, the thin film may have a film composition of a tungsten film, a ruthenium film, a copper film, a rhodium film, a molybdenum nitride film, a tungsten nitride film, or a titanium nitride film.

[0042] The thin film may include the aforementioned film components alone or in a selective area, but is not limited thereto and may also include SiH and SiOH.

[0043] The thin film can be used as a generally used diffusion prevention film, electrode film, or the like in semiconductor devices.

[0044] The thin film may be a stacked film of one or more selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru, and Ti.

[0045] In the present invention, the precursor compound for forming a thin film may be a precursor compound used for metal wiring or diffusion prevention purposes, or the like.

[0046] As an example, the precursor compound may have a structure having Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru and Ti as the central metal atom (M) and combined with ligands (L1, L2, L3, L4, L5, L6, etc.).

[0047] As a specific example, the precursor compound is a molecule having Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru and Ti as the central metal atom (M) and having one or more ligands composed of C, N, O, H, X (halogen). When the precursor has a vapor pressure of 0.01mTorr to 100Torr at 25°C, the effect of being used as the reducing agent can be maximized.

[0048] As an example, when the central metal is divalent, L1 and L2 can be bound to the central metal as ligands, and when the central metal is hexavalent, L1, L2, L3, L4, L5, and L6 can be bound to the central metal. The ligands corresponding to L1 to L6 can be the same as or different from each other.

[0049] As an example, L1, L2, L3, L4, L5 and L6 are -H or -R, which can be the same as or different from each other, wherein -R can be a C1-C10 alkyl group, a C1-C10 alkene or a C1-C10 alkane, and can be linear or cyclic, and the number n of L in L1, L2, L3 and L4 can be formed to be 2 to 6 according to the oxidation valence of the central metal.

[0050] As an example, when the central metal is divalent, L1 and L2 can be bound to the central metal as ligands, and when the central metal is hexavalent, L1, L2, L3, L4, L5, and L6 can be bound to the central metal. The ligands corresponding to L1 to L6 can be the same as or different from each other.

[0051] As a specific example, L1, L2, L3, L4, L5 and L6 are -H, -OR or -NR2, which can be the same as or different from each other, wherein -R can be H, C1-C10 alkyl, C1-C10 alkene, C1-C10 alkane, iPr or TBu, and in this case, has reaction energy suitable for replacement by the reducing agent described later.

[0052] As a specific example, L1, L2, L3, L4, L5 and L6 are -H or -X, which can be the same as or different from each other, wherein -X can be F, Cl, Br or I, and in this case, has a reaction energy suitable for replacement by the reducing agent described later.

[0053] As a specific example, L1, L2, L3, L4, L5 and L6 are L1, L2, L3, L4 are -H or -R, which can be the same as or different from each other, wherein -R can be a C1-C10 alkyl, a C1-C10 alkene or a C1-C10 alkane, and can have a linear or cyclic structure. In this case, it has reaction energy suitable for being replaced by the reducing agent described later.

[0054] As specific examples, L1, L2, L3, L4, L5 and L6 are -H, -OR or -NR2, which can be the same as or different from each other, wherein -R can be H, C1-C10 alkyl, C1-C10 alkene, C1-C10 alkane, iPr or tBu, and in this case, has reaction energy suitable for replacement by the reducing agent described later.

[0055] As a specific example, L1, L2, L3, L4, L5 and L6 are -H or -X, which can be the same as or different from each other, wherein -X can be F, Cl, Br or I, and in this case, has a reaction energy suitable for replacement by the reducing agent described later.

[0056] 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 to 2, and may also include trimethylenemethane ligands and derivatives thereof, but is not limited thereto.

[0057] [Chemical Formula 1]

[0058]

[0059] (In the chemical formula 1, R1 to R5 are independently selected from hydrogen, amino, silyl, alkyl having 1 to 8 carbon atoms, and aryl having 6 to 8 carbon atoms, excluding the case where R1 to R5 are all hydrogen.)

[0060] [Chemical Formula 2]

[0061]

[0062] (In Chemical Formula 2, X is H; F; Cl; Br; I; NO; CN; amidino; guanidino; ethylenediamine; propylenediamine; -NR6R7; -OR8; R9Cp, and linear, branched, or cyclic, saturated or unsaturated hydrocarbons substituted with one or more carbon (C), nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); R6, R7, R8, and R9 are 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 from 0 to 2.)

[0063] As an example, the derivative of the trimethylenemethane ligand may include a structure having a trimbenzylidenemethane ligand, a dibenzylidenemethane ligand, and the like.

[0064] As an example, the precursor compound with molybdenum (Mo) as the central metal may be molybdenum hexacarbonyl (Mo(CO)6), bis(ethylbenzene) molybdenum ((Ethylbenzene)2Mo), 2,6-diisopropylaniline tricarbonyl molybdenum ((2,6-diisopropylaniline)Mo(CO)3), (1,4-diisopropyl-1,4-diazabutadiene)Mo(CO)((1,4-diisopropyl-1,4-diazabutadiene)Mo(CO))、(Mo(CO)5PCl2Me、Molybdenum Acetate Dimer、(Ethylbenzene)Mo(allyl)2、MeCpMo(CO)2(allyl))、iprCpMo(CO)2(allyl))、Mo(thd)3、(MeCp)Mo(EMA)3、(tert-butylimido)Mo(MeCp)2、TDMAMo、dihydro Molybdenum disulfide (Cp2MoH2), Molybdenum dithiocarbamate (Mo(Dithiocabate)4), (tert-butylimido)2MoCl(aminothiolate)), (tert-butylimido)2Mo(tert-butylthiol)(aminothiolate)), (tert-butylimido)2Mo(tert-butylthiol)(aminothiolate)), (tert-butylimido)2Mo(aminothiolate) (tert-butylimido)2Mo(aminothiolate)2), ((tert-butylimide)2Mo(tert-butylthiol)2((tert-butylimido)2Mo(tert-butylthiol)2), (tert-butylimido)2Mo(tert-butylthiol)2), (tert-butylimido)2Mo(tert-butylthiol)2) Butylimide)2Mo(tert-butylamine)2((tert-butylimido)2Mo(tert-butylamine)2), (tert-butylimide)2Mo(CpEMA)((tert-butylimido)2Mo(CpEMA ))、MoO2(ipr-amidinate)2)、((tert-butylimido)2Mo(ipr-amidinate)2)、(tert-butylimido)2Mo(tert-butylimido)2Mo(tert-butoxy)2)、(tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine)((tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine)), (tert-butylimide) 2Mo(hydrazido)Cl((tert-butylimido) 2Mo(hydrazido)Cl), MoO2(Dithiocarbamate)2), (1,4-ditert-butyl-1,4-diazabutadiene) Mo(tert-butylimido)2), molybdenum dioxide dichloride (MoO2Cl2), etc.

[0065] Among them, the molybdenum dioxide dichloride (MoO2Cl2), bis(ethylbenzene) molybdenum ((Ethylbenzene)2Mo), 2,6-diisopropylaniline tricarbonyl molybdenum ((2,6-diisopropylaniline)Mo(CO)3), (benzene)Mo(CO)3((benzene)Mo(CO)3), and (1,4-diisopropyl-1,4-diazabutaiene)Mo(CO)3((1,4-diisopropyl-1,4-diazabutaiene)Mo(CO)3) can be compounds represented by the following chemical formulas 3-1 to 3-5, respectively.

[0066] [Chemical Formula 3-1] to [Chemical Formula 3-5]

[0067]

[0068] Among them, the Mo(CO)5PCl2Me, molybdenum acetate (II) dimer (Molybdenum Acetate Dimer), (Ethylbenzene)Mo(allyl)2, MeCpMo(CO)2(allyl), i prCpMo(CO)2(allyl)( i prCpMo(CO)2(allyl)) may be compounds represented by the following Chemical Formulas 3-6 to 3-10, respectively.

[0069] [Chemical Formula 3-6] to [Chemical Formula 3-10]

[0070]

[0071] Among them, the Mo(thd)3, (MeCp)Mo(EMA)3, (tert-butylimido)Mo(MeCp)2((tert-butylimido)Mo(MeCp)2), TDMAMo, and dihydrogenated molybdenumocene (Cp2MoH2) can be compounds represented by the following chemical formulas 3-11 to 3-15, respectively.

[0072] [Chemical Formula 3-11] to [Chemical Formula 3-15]

[0073]

[0074] Among them, the molybdenum dithiocarbamate (Mo(Dithiocabate)4), (tert-butylimido)2MoCl(aminothiolate)), (tert-butylimido)2Mo(tert-butylthiol)(aminothiolate)), (tert-butylimido)2Mo(aminothiolate)), (tert-butylimido)2Mo(aminothiolate)2), and (tert-butylimido)2Mo(tert-butylthiol)2) can be compounds represented by the following Chemical Formulas 3-16 to 3-20, respectively.

[0075] [Chemical Formula 3-16] to [Chemical Formula 3-20]

[0076]

[0077] Among them, the (tert-butylimide)2Mo(tert-butylamine)2((tert-butylimido)2Mo(tert-butylamine)2), (tert-butylimide)2Mo(CpEMA)((tert-butylimido)2Mo(CpEMA)), MoO2(ipr-amidinate)2, and (tert-butylimide)2Mo(ipr-amidinate)2((tert-butylimido)2Mo(ipr-amidinate)2) can be compounds represented by the following chemical formulas 3-20 to 3-24, respectively.

[0078] [Chemical Formula 3-20] to [Chemical Formula 3-24]

[0079]

[0080] Among them, the (tert-butylimido)2Mo(tert-butoxy)2, (tert-butylimido)2Mo(N,N-dimethyldiethylenetriamine) triamine)), (tert-butylimide)2Mo(hydrazido)Cl((tert-butylimido)2Mo(hydrazido)Cl), MoO2(dithiocarbamate)2), (1,4-ditert-butyl-1,4-diazabutadiene)Mo(tert-butylimide)2((1,4-ditert-butyl-1,4-diazabutadiene)Mo(tert-butylimido)2), dichloromolybdenum dioxide (MoO2Cl2), (tert-butylimide)2Mo(dimethylamide)2((tert-butylimido)2Mo(dimethylamide)2), and (toluene)2Mo((Methylbenzene)2Mo) can be compounds represented by the following chemical formulas 3-25 to 3-31, respectively.

[0081] [Chemical Formula 3-25] to [Chemical Formula 3-31]

[0082]

[0083] As an example, the precursor compound may be mixed with a non-polar solvent for use. In this case, there is an advantage that the viscosity or vapor pressure of the precursor compound can be easily adjusted.

[0084] The reducing agent of the present invention can effectively displace the ligand by lowering the activation energy of the precursor compound adsorbed on the substrate.

[0085] As an example, the reducing agent (using the nitriding agent or additional reducing agent described later as needed) can be used to replace the ligand on the entire substrate or a portion of the substrate on which the thin film is formed.

[0086] The reducing agent is characterized in that it is one or more selected from hydrogen iodide, an aqueous solution of hydrogen iodide, hydrogen bromide and an aqueous solution of hydrogen bromide. In this case, it has the following effects: it fully acts as a reducing agent at a relatively low process temperature to suppress side reactions occurring when forming a thin film, and due to the reduction of process by-products in the thin film, corrosion or degradation is reduced, and not only the film quality is improved, such as the crystallinity of the thin film, but also the thickness uniformity of the thin film can be greatly improved when the thin film is formed on a highly integrated substrate or a substrate with a complex structure.

[0087] As a specific example, the reducing agent can be pure 3N to 15N hydrogen iodide, or a gas mixture of 1 wt% to 99 wt% of 3N to 15N hydrogen iodide and an inert gas with the remainder making the total amount reach 100 wt%, or an aqueous solution mixture of 0.5 wt% to 70 wt% of 3N to 15N hydrogen iodide and water with the remainder making the total amount reach 100 wt%. When 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 film density and the electrical properties of the film are better.

[0088] Preferably, the reducing agent may be pure 5N to 6N hydrogen iodide, or a gaseous mixture of 1 wt% to 99 wt% 5N to 6N hydrogen iodide and an inert gas with the remainder making up 100 wt% of the total amount, or an aqueous solution mixture of 0.5 wt% to 70 wt% 5N to 6N hydrogen iodide and water with the remainder making up 100 wt% of the total amount, wherein the inert gas may be nitrogen, helium or argon with a purity of 4N to 9N. In this case, side reactions occurring during thin film formation are suppressed, the film growth rate is adjusted, and corrosion or degradation is reduced due to the reduction of process byproducts in the film. In addition, the film quality is improved, such as improved film crystallinity, and the thickness uniformity of the film can be greatly improved when the film is formed on a highly integrated substrate or a substrate having a complex structure.

[0089] Preferably, the reducing agent may be pure 5N to 6N hydrogen iodide, or a gas mixture of 1 wt% to 99 wt% of 5N to 6N hydrogen iodide and an inert gas with the remainder making up the total amount to 100 wt%, or an aqueous solution mixture of 0.5 wt% to 70 wt% of 5N to 6N hydrogen iodide and water with the remainder making up the total amount to 100 wt%, wherein the inert gas may be nitrogen, helium or argon with a purity of 4N to 9N.

[0090] In this case, at a relatively low process temperature where the precursor does not thermally decompose, a reducing effect is fully provided to the precursor compound adsorbed on the substrate, thereby having the advantages of greatly improving the thickness uniformity of the thin film when forming a thin film on a highly integrated substrate or a substrate having a complex structure, effectively protecting the surface of the substrate by preventing adsorption not only by the thin film precursor but also by preventing adsorption of process by-products, reducing the reaction rate, and effectively removing process by-products.

[0091] Preferably, the reducing agent may be a compound having a purity of 99.9% or more, a compound having a purity of 99.95% or more, or a compound having a purity of 99.99% or more. For reference, when a compound having a purity of less than 99% is used, impurities may remain in the film or may cause side reactions with the precursor or reactant, so substances having a purity of 99% or more are used whenever possible.

[0092] As an example, the film may include 100 ppm or less of halogen compounds. For reference, if the residual halogen content is too high, for example, when using a nitriding agent described later at a temperature of 200°C to 300°C, chlorides such as NH4Cl will be generated, and these chlorides will remain in the film, which is not preferred.

[0093] The thin film may be used as an etching stopper film, an electrode film, or the like, but is not limited thereto.

[0094] In particular, while forming a relatively sparse thin film, the growth rate of the formed thin film is greatly reduced. Therefore, even if it is applied to a substrate with a complex structure, the uniformity of the thin film can be ensured. In particular, it can be deposited with a thin thickness and can provide an effect of not only improving the amount of O, Si, metal, and metal oxides remaining as process by-products, but also improving the amount of carbon residue that has been difficult to reduce in the past.

[0095] According to an implementation example of the present invention, a thin film forming method is characterized in that it includes: a step of injecting a precursor compound into a chamber so that it is adsorbed on the surface of a substrate; and a step of injecting a reducing agent into the chamber to form a deposited film, wherein, when one or more selected from the aforementioned hydrogen iodide, hydrogen iodide aqueous solution, hydrogen bromide and hydrogen bromide aqueous solution is used as the reducing agent, the reduction of the precursor adsorbed on the substrate is effectively carried out at a relatively low process temperature to ensure that the precursor does not undergo thermal decomposition, so as to appropriately reduce the film growth rate, thereby greatly improving the film uniformity even when forming a thin film on a highly integrated substrate or a substrate with a complex structure.

[0096] The reducing agent and the precursor compound may be delivered into the chamber via a variable flow control (VFC) method, a direct liquid injection (DLI) method, or a liquid delivery system (LDS) method.

[0097] The ratio of the amount of the precursor compound to the reducing agent fed into the chamber (mg / cycle) may be 1:1 to 1:20.

[0098] In the step of injecting the reducing agent into the substrate surface, the time for supplying the reducing agent to the substrate surface (Feeding Time, seconds (sec)) is preferably 0.01 to 10 seconds per cycle, more preferably 0.02 to 8 seconds, even more preferably 0.04 to 6 seconds, and further preferably 0.05 to 4 seconds. Within this range, the film growth rate is low and the step coverage and economy are excellent.

[0099] In this specification, the feeding time of the reducing agent is based on a flow rate of 0.1 mg / cycle to 8000 mg / cycle when the volume of the chamber is 15 L to 20 L, and more specifically, based on a flow rate of 10 mg / cycle to 5000 mg / cycle when the volume of the chamber is 18 L.

[0100] As a specific example, the thin film forming method may include: a step of injecting a precursor compound into a chamber so that it is adsorbed on the surface of a substrate; a step of performing a first purge of the interior of the chamber using a purge gas; a step of injecting the aforementioned reducing agent into the chamber to reduce the adsorbed precursor compound; and a step of performing a second purge of the interior of the chamber using a purge gas.

[0101] All the above steps can be taken as a unit cycle and the cycle can be repeated until a film of desired thickness is obtained. When the reducing agent is added sequentially after the precursor compound in one cycle to improve the film quality in this way, it has the advantages of effectively removing the process by-products generated to reduce the resistivity of the film, and greatly improving the step coverage, improving the film uniformity, and improving the film quality such as electrical properties, dielectric properties, and film density.

[0102] The chamber may 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.

[0103] The substrate loaded in the chamber may be heated to 100° C. to 800° C.

[0104] The method may include performing a plasma post-treatment after the reducing agent or precursor compound is vaporized and injected, thereby improving the growth rate of the thin film while reducing process byproducts.

[0105] According to another embodiment of the present invention, a thin film forming method is characterized in that it includes: a step of injecting a precursor compound into a chamber so that it is adsorbed on the surface of a substrate; a step of injecting a reducing agent into the chamber to form a deposited film; and a step of injecting a nitriding agent or an additional reducing agent into the chamber to form a nitride film. In this case, by effectively performing the reduction of the precursor adsorbed on the substrate, the film growth rate is appropriately reduced, thereby having the effect of greatly improving the film quality such as electrical properties and film density even when a thin film is formed on a highly integrated substrate or a substrate with a complex structure.

[0106] As a specific example, the thin film forming method may include: a step of injecting a precursor compound into the chamber so that it is adsorbed on the surface of the substrate; a step of purging the interior of the chamber for a first time using a purge gas; a step of injecting the aforementioned reducing agent into the chamber to reduce the adsorbed precursor compound; a step of purging the interior of the chamber for a second time using a purge gas; a step of injecting a nitriding agent or an additional reducing agent into the chamber to form a thin film; and a step of purging the interior of the chamber for a third time using a purge gas.

[0107] All the above steps can be used as a unit cycle and the cycle can be repeated until a film of desired thickness is obtained. When the reducing agent is sequentially added after the precursor compound in one cycle to improve the film quality in this way, it has the following advantages: the process by-products can be significantly reduced and the step coverage can be greatly improved, the resistivity of the film can be reduced by increasing the crystallinity of the film, and even when applied to high aspect ratio semiconductor devices, the thickness uniformity of the film can be greatly improved, thereby not only ensuring the reliability of the semiconductor device, but also improving the film quality such as electrical properties and film density.

[0108] The chamber may 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.

[0109] The substrate loaded in the chamber may be heated to 100° C. to 800° C.

[0110] The nitriding agent may be nitrogen, ammonia, etc.

[0111] The additional reducing agent may be hydrogen or the like.

[0112] In this specification, the feeding time of the nitriding agent or the additional reducing agent is based on a flow rate of 0.1 mg / cycle to 8000 mg / cycle when the volume of the chamber is 15L to 20L. More specifically, in a chamber volume of 18L, the flow rate is based on 10 mg / cycle to 5000 mg / cycle.

[0113] In the step of purging the unadsorbed precursor compounds, the amount of purge gas introduced into the ALD chamber is not particularly limited as long as it is sufficient to remove the unadsorbed precursor compounds. As an example, the amount of purge gas introduced into the ALD chamber can be 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times, based on the volume of the precursor compound introduced into the ALD chamber. Within this range, the unadsorbed precursor compounds can be sufficiently removed to uniformly form a thin film and prevent degradation of film quality. The amounts of purge gas and precursor compound introduced are based on one cycle, and the volume of the precursor compound represents the volume of the vapor of the vaporized precursor compound.

[0114] Furthermore, in the purge step performed immediately after the additional reducing agent supplying step, as an example, the amount of purge gas introduced into the ALD chamber may be 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times, based on the volume of the additional reducing agent introduced into the ALD chamber. Within this range, the desired effect can be fully achieved. The amounts of purge gas and additional reducing agent introduced are each based on one cycle.

[0115] Preferably, the reducing agent, precursor compound, nitriding agent or additional reducing agent can be delivered into the atomic layer deposition (ALD) chamber by vapor flow control (VFC), direct liquid injection (DLI) or liquid delivery system (LDS), more preferably, delivered into the chamber by vapor flow control (VFC).

[0116] As an example, the substrate loaded into the chamber can be heated to 100°C to 800°C, and as a specific example, can be heated to 300°C to 600°C. The reducing agent or precursor compound can be injected onto the substrate in an unheated state or a heated state. Furthermore, the heating conditions can be adjusted during the deposition process after injection in an unheated state based on deposition efficiency. As an example, the reducing agent or precursor compound can be injected onto the substrate at a temperature of 50°C to 400°C for 1 second to 20 seconds.

[0117] The ratio of the amount of the precursor compound to the reducing agent added into the chamber (mg / cycle) can preferably be 1:1 to 1:20, more preferably 1:2 to 1:15, even more preferably 1:2 to 1:12, and further preferably 1:2.5 to 1:10. Within this range, the effect of improving step coverage and reducing process by-products is significant.

[0118] As an example, the thin film forming method can be implemented at a deposition temperature in the range of 100°C to 800°C, preferably in the range of 300°C to 600°C, more preferably in the range of 300°C to 500°C, and even more preferably in the range of 300°C to 400°C. Within this range, it has the effect of growing a thin film with excellent film quality while realizing the process characteristics of atomic layer deposition (ALD).

[0119] As an example, the thin film forming method can be implemented at a deposition pressure in the range of 0.01 Torr to 20 Torr, preferably in the range of 0.1 Torr to 20 Torr, more preferably in the range of 0.1 Torr to 10 Torr, and most preferably in the range of 0.3 Torr to 7 Torr. Within this range, a thin film with uniform thickness can be obtained.

[0120] In this specification, the deposition temperature and the deposition pressure may be measured by the temperature and pressure formed in the deposition chamber, or by the temperature and pressure applied to the substrate in the deposition chamber.

[0121] Preferably, the thin film forming method may include: a step of raising the temperature in the chamber to a deposition temperature before the precursor compound is introduced into the chamber; and / or a step of injecting an inert gas into the chamber for purging before the precursor compound is introduced into the chamber.

[0122] In the thin film forming method, the film thickness is measured by secondary ion mass spectrometry (SIMS). The residual halogen intensity (c / s) in the benchmark film can be preferably less than 100,000, more preferably less than 70,000, more preferably less than 50,000, and further preferably less than 10,000. As a preferred embodiment, it can be less than 5,000, more preferably 10 to 4,000, and even more preferably 10 to 3,000. Within this range, the effect of preventing corrosion and degradation is excellent.

[0123] In this specification, the purge is preferably 1000 sccm to 50000 sccm (Standard Cubic Centimeter per Minute), more preferably 2000 sccm to 30000 sccm, and even more preferably 2500 sccm to 15000 sccm. Within this range, the film growth rate of each cycle is properly controlled, and deposition is performed in an atomic mono-layer or close thereto, which has advantages in terms of film quality.

[0124] In addition, the present invention, as a thin film manufacturing apparatus capable of implementing the thin film manufacturing method, may include a thin film manufacturing apparatus comprising: an atomic layer deposition (ALD) chamber; a first vaporizer for vaporizing a precursor compound; a first delivery device for delivering the vaporized precursor compound into the atomic layer deposition (ALD) chamber; a second vaporizer for vaporizing a reducing agent; a second delivery device for delivering the vaporized reducing agent into the atomic layer deposition (ALD) chamber; and a third delivery device for delivering a nitriding agent or an additional reducing agent into the atomic layer deposition (ALD) chamber. The vaporizer and delivery device may be any commonly used vaporizer and delivery device in the technical field to which the present invention pertains, and are not particularly limited.

[0125] As a specific example, the thin film forming method is described. First, a substrate on which a thin film is to be formed is placed in a deposition chamber capable of performing atomic layer deposition.

[0126] The substrate may include a semiconductor substrate such as a silicon substrate or silicon oxide.

[0127] The substrate may further have a conductive layer or an insulating layer formed on its upper portion.

[0128] In order to deposit a thin film on the substrate in the deposition chamber, the reducing agent, the precursor compound or a mixture thereof and the non-polar solvent are prepared respectively.

[0129] Subsequently, the prepared precursor compound or its mixture with a non-polar solvent (hereinafter referred to as the "thin film forming composition") is injected into a vaporizer, converted into a vapor phase, and transported to a deposition chamber so that it is adsorbed on the substrate, and the unadsorbed precursor compound or its mixture with a non-polar solvent is purged.

[0130] Preferably, the non-polar solvent may be one or more selected from the group consisting of alkanes and cycloalkanes. In this case, there is an advantage that, although the organic solvent includes organic solvents having low reactivity and solubility and easy moisture management, step coverage is improved when the deposition temperature increases during the film formation process.

[0131] As a more preferred example, the non-polar solvent may include C1 to C10 alkane or C3 to C10 cycloalkane, preferably C3 to C10 cycloalkane, in which case it has the advantages of low reactivity and solubility and easy moisture management.

[0132] In this specification, C1, C3, etc. represent the number of carbon atoms.

[0133] Preferably, the cycloalkane may be a C3 to C10 monocycloalkane. Among the monocycloalkane, cyclopentane is liquid at room temperature and has the highest vapor pressure, and is therefore preferred in the vapor deposition process, but is not limited thereto.

[0134] As an example, the solubility of the non-polar solvent in water (25°C) is less than 200 mg / L, preferably 50 mg / L to 400 mg / L, and more preferably 135 mg / L to 175 mg / L. Within this range, it has the advantages of low reactivity to precursor compounds and easy moisture management.

[0135] In this specification, solubility is not particularly limited as long as it is based on a measurement method or standard commonly used in the technical field to which the present invention belongs. As an example, a saturated solution can be measured according to High Performance Liquid Chromatography (HPLC).

[0136] Preferably, based on the total weight of the precursor compound and the non-polar solvent, the content of the non-polar solvent can be 5 wt % to 95 wt %, more preferably 10 wt % to 90 wt %, even more preferably 40 wt % to 90 wt %, most preferably 70 wt % to 90 wt %.

[0137] When the content of the non-polar solvent input exceeds the upper limit value, impurities will be induced, thereby increasing the resistance and the value of impurities in the film. When the content of the organic solvent input is less than the lower limit value, there are disadvantages that the effect of improving the step coverage due to the addition of the solvent and the effect of reducing impurities such as chloride (Cl) ions are not significant.

[0138] Next, the prepared reducing agent is injected into the vaporizer, converted into a vapor phase, and transported to the deposition chamber to be adsorbed, and the unadsorbed reducing agent is purged.

[0139] In this specification, as an example, the method of delivering the reducing agent and precursor compound (thin film forming composition) to the deposition chamber can use a method of delivering volatile gas (Vapor Flow Control, VFC) using a gas phase flow control (Mass Flow Controller, MFC) method or a method of delivering liquid (Liquid Delivery System, LDS) using a liquid phase flow control (Liquid Mass Flow Controller, LMFC) method, and preferably, the gas phase flow control (Variable Flow Control, VFC) method is used.

[0140] At this time, as a transport gas or dilution gas for transferring the reducing agent and precursor compound to the substrate, one or a mixed gas of two or more selected from the group consisting of argon (Ar), nitrogen (N2), and helium (He) can be used, but is not limited.

[0141] In this specification, as an example, an inert gas may be used as the purge gas, and preferably, the carrier gas or the diluent gas may be used.

[0142] 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 belongs. Preferred nitriding agents include nitrogen (N2), hydrazine gas (N2H4), or a mixture of nitrogen and hydrogen, and additional reducing agents include hydrogen (H2).

[0143] The nitriding agent reacts with the precursor compound adsorbed on the substrate to form a nitride film.

[0144] The additional reducing agent reacts with the precursor compound adsorbed on the substrate to form a metal film.

[0145] Next, the unreacted residual nitriding agent or additional reducing agent is purged with an inert gas, thereby removing not only the excess nitriding agent or additional reducing agent but also the generated by-products.

[0146] As described above, as an example, the thin film forming method can take the following steps as a unit cycle, and repeat the unit cycle to form a thin film of a desired thickness, the steps including: a step of adsorbing a precursor compound / thin film forming composition on a substrate; a step of purging unadsorbed precursor compounds; a step of adsorbing a reducing agent on a substrate; a step of purging unadsorbed reducing agents; a step of supplying a nitriding agent or an additional reducing agent as needed; and a step of purging residual nitriding agent or additional reducing agent as needed.

[0147] As an example, the unit cycle can be repeated 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 film properties are well expressed.

[0148] Furthermore, the present invention provides a semiconductor substrate, characterized in that the semiconductor substrate is manufactured using the thin film forming method of this specification. In this case, the thickness uniformity of the thin film is very excellent and the density and electrical characteristics of the thin film are excellent.

[0149] Preferably, the thickness of the film manufactured above is less than 30nm, and based on the film thickness of 10nm, the resistivity value is 5μΩ·cm to 2000μΩ·cm, the halogen content is less than 10000ppm, and the step coverage is more than 90%. Within this range, as an anti-diffusion film, it has excellent performance and reduces the corrosion of metal wiring materials, but is not limited to this.

[0150] As an example, the film thickness may be 0.1 nm to 30 nm, preferably 1 nm to 20 nm, and more preferably 2 nm to 10 nm. Within this range, the film has excellent properties.

[0151] As an example, based on a film thickness of 10 nm, the resistivity value of the film can be 0.1 μΩ·cm to 400 μΩ·cm, preferably 15 μΩ·cm to 300 μΩ·cm, and more preferably 20 μΩ·cm to 290 μΩ·cm. Within this range, the film has excellent properties.

[0152] Preferably, the halogen content of the film may be less than 10000 ppm or 1 ppm to 9000 ppm, more preferably 5 ppm to 8500 ppm, and even more preferably 100 ppm to 1000 ppm. Within this range, the film has excellent properties and reduces the film growth rate. As an example, the residual halogen in the film may be Cl2, Cl or Cl - The lower the residual halogen content in the film, the better the film quality, so it is preferred.

[0153] As an example, the step coverage of the film is above 90%, preferably above 92%, and more preferably above 95%. Within this range, even a film with a complex structure can be easily deposited on the substrate, and therefore has the advantage of being applicable to the next generation of semiconductor devices.

[0154] Preferably, the thickness of the film manufactured above is less than 20nm. Taking the film thickness of 10nm as the benchmark, the content of carbon, nitrogen and halogen is less than 10000ppm, and the step coverage is more than 90%. Within this range, it has excellent performance as a dielectric film or barrier film, but is not limited to this.

[0155] Below, preferred embodiments and drawings are presented to help understand the present invention. Those skilled in the art will appreciate that the following embodiments and drawings are only used to illustrate the present invention, and that various changes and modifications may be made within the scope of the scope of the present invention and the technical concept. Of course, these variations and modifications also fall within the scope of protection of the attached patent claims.

[0156] [Example]

[0157] Example 1

[0158] An atomic layer deposition (ALD) deposition process was performed using 5N HI as a reducing agent and a precursor having the following chemical formula BTBMMo as a precursor compound.

[0159] [Chemical formula]

[0160]

[0161] First, the prepared precursor compounds were placed in separate canisters and supplied at room temperature to a separate vaporizer heated to 150°C using a liquid mass flow controller (LMFC) at a flow rate of 0.1 g / min. The BTBMMo precursor, vaporized in the vaporizer, was introduced into the deposition chamber for 3 seconds, followed by an argon purge at 5000 sccm for 10 seconds. The pressure within the reaction chamber was maintained at 2.5 Torr.

[0162] Next, the prepared reducing agent is placed in a tank and supplied to the chamber at a flow rate of 1000 sccm using a mass flow controller (MFC) at room temperature. The reducing agent, which has been vaporized in the vaporizer, is added to the deposition chamber loaded with the substrate for 2 seconds, and then argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement an argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr. The deposition temperature is maintained at 350°C, and the above process is repeated 200 to 400 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0163] For the manufactured thin film (MoN metal film), the thickness of the film was measured using an ellipsometer (a device that can use the polarization properties of light to measure optical properties such as the thickness or refractive index of a thin film) and divided by the number of cycles to calculate the thickness of the film deposited per cycle to be 10nm. The film composition was analyzed by Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). In addition, the surface resistance was measured using a four-probe measurement method, and the resistivity value was calculated using the measured thickness.

[0164] Example 2

[0165] An atomic layer deposition (ALD) deposition process was performed using 5N HI and NH 3 as reducing agents and a precursor compound having the following chemical formula BTBMMo.

[0166] [Chemical formula]

[0167]

[0168] First, the prepared precursor compounds were placed in separate canisters and supplied at room temperature to a separate vaporizer heated to 150°C using a liquid mass flow controller (LMFC) at a flow rate of 0.1 g / min. The BTBMMo precursor, vaporized in the vaporizer, was introduced into the deposition chamber for 3 seconds, followed by an argon purge at 5000 sccm for 10 seconds. The pressure within the reaction chamber was maintained at 2.5 Torr.

[0169] Next, the prepared reducing agent HI is loaded into a tank 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 into a vapor phase in the vaporizer is added to the deposition chamber loaded with the substrate for 2 seconds, and then argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement argon purge. Furthermore, after the reducing agent NH3 is supplied into the chamber at a flow rate of 1000 sccm, argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr. The deposition temperature is maintained at 350°C, and the process as described above is repeated 200 to 400 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0170] For the manufactured thin film (MoN metal film), the thickness of the film was measured using an ellipsometer (a device that can use the polarization properties of light to measure optical properties such as the thickness or refractive index of a thin film) and divided by the number of cycles to calculate the thickness of the film deposited per cycle to be 10nm. The film composition was analyzed by Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). In addition, the surface resistance was measured using a four-probe measurement method, and the resistivity value was calculated using the measured thickness.

[0171] Example 3

[0172] An atomic layer deposition (ALD) deposition process was performed using 5N HI as a reducing agent and a precursor having the following chemical formula BTBTBMo as a precursor compound.

[0173] [Chemical formula]

[0174]

[0175] First, the prepared precursor compounds were placed in separate canisters and supplied at room temperature to a separate vaporizer heated to 150°C using a liquid mass flow controller (LMFC) at a flow rate of 0.1 g / min. The BTBTBMo precursor, vaporized in the vaporizer, was introduced into the deposition chamber for 3 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to purge the chamber. The pressure within the reaction chamber was maintained at 2.5 Torr.

[0176] Next, the prepared reducing agent is placed in a tank and supplied to the chamber at a flow rate of 1000 sccm using a mass flow controller (MFC) at room temperature. The reducing agent, which has been vaporized in the vaporizer, is added to the deposition chamber loaded with the substrate for 2 seconds, and then argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement an argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr. The deposition temperature is maintained at 350°C, and the above process is repeated 200 to 400 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0177] For the manufactured thin film (MoN metal film), the thickness of the film was measured using an ellipsometer (a device that can use the polarization properties of light to measure optical properties such as the thickness or refractive index of a thin film) and divided by the number of cycles to calculate the thickness of the film deposited per cycle to be 10nm. The film composition was analyzed by Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). In addition, the surface resistance was measured using a four-probe measurement method, and the resistivity value was calculated using the measured thickness.

[0178] Example 4

[0179] An atomic layer deposition (ALD) deposition process was performed using 5N HI and NH 3 as reducing agents and a precursor having the following chemical formula BTBTBMo as a precursor compound.

[0180] [Chemical formula]

[0181]

[0182] First, the prepared precursor compounds were placed in separate canisters and supplied at room temperature to a separate vaporizer heated to 150°C using a liquid mass flow controller (LMFC) at a flow rate of 0.1 g / min. The BTBTBMo precursor, vaporized in the vaporizer, was introduced into the deposition chamber for 3 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to purge the chamber. The pressure within the reaction chamber was maintained at 2.5 Torr.

[0183] Next, the prepared reducing agent HI is loaded into a tank 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 into a vapor phase in the vaporizer is added to the deposition chamber loaded with the substrate for 2 seconds, and then argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement argon purge. Furthermore, after the reducing agent NH3 is supplied into the chamber at a flow rate of 1000 sccm, argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr. The deposition temperature is maintained at 350°C, and the process as described above is repeated 200 to 400 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0184] For the manufactured thin film (MoN metal film), the thickness of the film was measured using an ellipsometer (a device that can measure optical properties such as the thickness or refractive index of a film using the polarization properties of light). The thickness of the film deposited per cycle was calculated to be 10nm. The film composition was analyzed by Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). In addition, the surface resistance was measured using the four-probe measurement method, and the resistivity value was calculated using the measured thickness.

[0185] Example 5

[0186] An atomic layer deposition (ALD) deposition process was performed using 5N HI as a reducing agent and a precursor of the following chemical formula Mo(CO)6 as a precursor compound.

[0187] [Chemical formula]

[0188]

[0189] First, the prepared precursor compounds were placed in a separate tank and heated to 50°C. Argon was used as a carrier gas and the Mo(CO)6 precursor was introduced into the deposition chamber at a flow rate of 50 sccm for 3 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr.

[0190] Next, the prepared reducing agent is placed in a tank and supplied to the chamber at a flow rate of 1000 sccm using a mass flow controller (MFC) at room temperature. The reducing agent, which is vaporized in the vaporizer into a vapor phase, is added to the deposition chamber loaded with the substrate for 2 seconds, and then argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement an argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr. The deposition temperature is maintained at 375°C, and the above process is repeated 50 to 200 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0191] The thickness of the produced thin film (Mo metal film) was measured using an ellipsometer (a device that uses the polarization properties of light to measure optical properties such as film thickness or refractive index). The thickness of the film deposited per cycle was divided by the number of cycles to calculate a thickness of 10 nm. The surface resistance was measured using a four-probe measurement method, and the resistivity value was calculated using the measured thickness. The crystallinity of the Mo film was confirmed by X-ray diffraction (XRD) analysis.

[0192] Example 6

[0193] An atomic layer deposition (ALD) deposition process was performed using 5N HI as a reducing agent and a precursor having the following chemical formula Mo(tol)2 as a precursor compound.

[0194] [Chemical formula]

[0195]

[0196] First, the prepared precursor compounds were placed in a separate tank and heated to 130°C. The Mo(tol)2 precursor was then introduced into the deposition chamber using argon as a carrier gas at a flow rate of 50 sccm for 10 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was maintained at 2.5 Torr.

[0197] Next, the prepared reducing agent is placed in a tank and supplied to the chamber at a flow rate of 1000 sccm using a mass flow controller (MFC) at room temperature. The reducing agent, which is vaporized in the vaporizer into a vapor phase, is added to the deposition chamber loaded with the substrate for 2 seconds, and then argon is supplied at a flow rate of 5000 sccm for 10 seconds to implement an argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr. The deposition temperature is maintained at 250°C, and the above process is repeated 30 to 300 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0198] The thickness of the fabricated thin film (Mo metal film) was measured using an ellipsometer (a device that uses the polarization properties of light to measure optical properties such as film thickness or refractive index). Dividing the thickness by the number of cycles, the thickness of the film deposited per cycle was calculated to be 10 nm. The surface resistance was measured using a four-probe method, and the resistivity value was calculated using the measured thickness.

[0199] [Comparative Example]

[0200] Comparative Example 1

[0201] An atomic layer deposition (ALD) deposition process was performed using NH 3 as a reducing agent and a precursor having the following chemical formula BTBMMo as a precursor compound.

[0202] [Chemical formula]

[0203]

[0204] First, the prepared precursor compounds were placed in separate canisters and supplied at room temperature to a separate vaporizer heated to 150°C using a liquid mass flow controller (LMFC) at a flow rate of 0.1 g / min. The BTBMMo precursor, vaporized in the vaporizer, was introduced into the deposition chamber for 3 seconds, followed by an argon purge at 5000 sccm for 10 seconds. The pressure within the reaction chamber was maintained at 2.5 Torr.

[0205] Next, the prepared reducing agent, NH3, was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vaporizer, was introduced into the deposition chamber loaded with the substrate for 2 seconds. Argon gas was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure within the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and the above process was repeated 200 to 400 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0206] For the manufactured thin film (MoN metal film), the thickness of the film was measured using an ellipsometer (a device that can measure optical properties such as the thickness or refractive index of a film using the polarization properties of light). The thickness of the film deposited per cycle was calculated to be 10nm. The film composition was analyzed by Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). In addition, the surface resistance was measured using the four-probe measurement method, and the resistivity value was calculated using the measured thickness.

[0207] Comparative Example 2

[0208] An atomic layer deposition (ALD) deposition process was performed using NH 3 as a reducing agent and a precursor having the following chemical formula BTBTBMo as a precursor compound.

[0209] [Chemical formula]

[0210]

[0211] First, the prepared precursor compounds were placed in separate canisters and supplied at room temperature to a separate vaporizer heated to 150°C using a liquid mass flow controller (LMFC) at a flow rate of 0.1 g / min. The BTBTBMo precursor, vaporized in the vaporizer, was introduced into the deposition chamber for 3 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to purge the chamber. The pressure within the reaction chamber was maintained at 2.5 Torr.

[0212] Next, the prepared reducing agent, NH3, was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vaporizer, was introduced into the deposition chamber loaded with the substrate for 2 seconds. Argon gas was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure within the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 350°C, and the above process was repeated 200 to 400 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0213] For the manufactured thin film (MoN metal film), the thickness of the film was measured using an ellipsometer (a device that can measure optical properties such as the thickness or refractive index of a film using the polarization properties of light). The thickness of the film deposited per cycle was calculated to be 10nm. The film composition was analyzed by Auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS). In addition, the surface resistance was measured using the four-probe measurement method, and the resistivity value was calculated using the measured thickness.

[0214] Comparative Example 3

[0215] An atomic layer deposition (ALD) deposition process was performed using NH 3 as a reducing agent and a precursor of the following chemical formula Mo(CO) 6 as a precursor compound.

[0216] [Chemical formula]

[0217]

[0218] First, the prepared precursor compounds were placed in a separate tank and heated to 50°C. Argon was used as a carrier gas and the Mo(CO)6 precursor was introduced into the deposition chamber at a flow rate of 50 sccm for 3 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was controlled at 2.5 Torr.

[0219] Next, the prepared reducing agent, NH3, was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vaporizer, was introduced into the deposition chamber loaded with the substrate for 2 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure within the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 375°C, and the above process was repeated 50 to 200 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0220] The thickness of the produced thin film (Mo metal film) was measured using an ellipsometer (a device that uses the polarization properties of light to measure optical properties such as film thickness or refractive index). The thickness of the film deposited per cycle was divided by the number of cycles to calculate a thickness of 10 nm. The surface resistance was measured using a four-probe measurement method, and the resistivity value was calculated using the measured thickness. The crystallinity of the Mo film was confirmed by X-ray diffraction (XRD) analysis.

[0221] Comparative Example 4

[0222] An atomic layer deposition (ALD) deposition process was performed using NH 3 as a reducing agent and a precursor of the following chemical formula Mo(tol) 2 as a precursor compound.

[0223] [Chemical formula]

[0224]

[0225] First, the prepared precursor compounds were placed in a separate tank and heated to 130°C. The Mo(tol)2 precursor was then introduced into the deposition chamber using argon as a carrier gas at a flow rate of 50 sccm for 10 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure in the reaction chamber was maintained at 2.5 Torr.

[0226] Next, the prepared reducing agent, NH3, was supplied to the chamber at a flow rate of 1000 sccm. The reducing agent, vaporized in the vaporizer, was introduced into the deposition chamber loaded with the substrate for 2 seconds. Argon was then supplied at a flow rate of 5000 sccm for 10 seconds to perform an argon purge. The pressure within the reaction chamber was controlled at 2.5 Torr. The deposition temperature was maintained at 250°C and 300°C, and the above process was repeated 30 to 300 times to form a self-limiting atomic layer film with a thickness of 10 nm.

[0227] The thickness of the fabricated thin film (Mo metal film) was measured using an ellipsometer (a device that uses the polarization properties of light to measure optical properties such as film thickness or refractive index). Dividing the thickness by the number of cycles, the thickness of the film deposited per cycle was calculated to be 10 nm. The surface resistance was measured using a four-probe method, and the resistivity value was calculated using the measured thickness.

[0228] [Test Example]

[0229] The obtained thin films of Examples 1 to 6 and Comparative Examples 1 to 4 were examined for impurity content, type and content analysis of elements constituting the material surface, deposition rate measurement, crystal structure, orientation, etc., by the following methods.

[0230] *Secondary ion mass spectrometry (SIMS) carbon impurities: Using ion sputtering, the carbon impurity counts were determined for a sputtering time of 50 seconds, which is less contamination in the substrate surface layer. The carbon impurity value was confirmed in the SIMS graph.

[0231] *Auger Electron Spectroscopy (AES): This technique measures the energy of Auger electrons emitted when a focused electron beam is incident on a material surface to analyze the types and contents of elements on the material surface.

[0232] *Deposition rate (GPC) measurement: For each of the films obtained in Examples 1 to 6 and Comparative Examples 1 to 4, the deposition rate (GPC) was measured as follows. Specifically, the deposition rate of films with a thickness of 3 nm to 30 nm was measured using an ellipsometer, using the unit:

[0233] *Grazing-incidence angle (incident angle, θ = 3°) X-ray diffraction: Surface diffraction analysis using Cu-Kα X-rays (Cu-Kα X-rays) confirms information such as crystal structure and orientation.

[0234]

Table 1

[0235]

[0236]

[0237] As shown in Table 1, it was confirmed that when using the reducing agent HI alone or in combination with NH3 according to the present invention, the amount of carbon impurities generated was significantly reduced compared to when using NH3 alone. Furthermore, as shown in Examples 1 and 2, AES analysis confirmed that carbon impurities were reduced to 0% during thin film formation, and SIMS results confirmed a reduction of over 91% in the number of detected carbon ions.

[0238] In addition, the increase in film density from 6.0 to 6.8 indicates that a very high-quality MoN film has been formed.

[0239]

Table 2

[0240]

[0241] As shown in Table 2 above, it can be confirmed that when the process using the reducing agent HI alone or the process using the reducing agent HI and NH3 in combination according to the present invention is adopted, the resistivity of the formed film is sharply reduced compared with the case where the reducing agent NH3 is used alone. In addition, the reduction of C impurities is also in the order of Comparative Example 2 > Example 4 > Example 3, and the effect is most significant when only the reducing agent HI is used.

[0242]

Table 3

[0243]

[0244] As shown in Table 3 above, when the reducing agent HI according to the present invention is used, the resistivity of the formed film is drastically reduced and the deposition rate is increased by more than 3 times compared to the case where only the reducing agent NH3 is used. In particular, XRD analysis was conducted at different process temperatures, and the results are shown below. Figure 2 middle. Figure 2 3 are XRD analysis diagrams of different process temperatures according to Example 5 of the present invention and Comparative Example 3.

[0245] as follows Figure 2 As shown, it can be seen that a pure Mo metal thin film is formed in Example 5.

[0246] In addition, the AES analysis results of Example 5 at different temperatures are shown below. Figure 1 middle.

[0247] Figure 1 : is a graph of the AES analysis results at different temperatures according to Example 5 of the present invention. Figure 1 As shown in FIG, it is confirmed that the types and contents of the elements formed vary according to the process temperature.

[0248]

Table 4

[0249]

[0250] As shown in Table 4 above, when the reducing agent HI according to the present invention is used, the resistivity of the formed film is drastically reduced and the deposition rate is increased by more than 2 times compared to the case where only the reducing agent NH3 is used. In particular, XRD analysis was performed and the results are shown below. Figure 3 middle. Figure 3 1 and 2 are XRD analysis diagrams of Example 6 and Comparative Example 4 according to the present invention.

[0251] as follows Figure 3 As shown, it can be seen that a pure Mo metal film is partially formed in Example 6.

[0252] The results confirmed the following effects: by using a specified reducing agent, the thickness uniformity of the thin film can be greatly improved even when forming a thin film on a highly integrated or complex substrate, and the film quality can be effectively improved by reducing impurities and improving the film density, resistivity, etc.

Claims

1. A thin film forming method, characterized in that: include: injecting a precursor compound into the chamber to allow it to adsorb on the surface of the substrate, and injecting a reducing agent into the chamber to form a deposited film; The reducing agent is one or more selected from the group consisting of hydrogen iodide, an aqueous hydrogen iodide solution, hydrogen bromide, and an aqueous hydrogen bromide solution.

2. The thin film forming method according to claim 1, wherein The reducing agent is pure 3N to 15N hydrogen iodide, or a gas mixture of 1% to 99% by weight of 3N to 15N hydrogen iodide and an inert gas with the remainder making up 100% by weight, or an aqueous solution mixture of 0.5% to 70% by weight of 3N to 15N hydrogen iodide and water with the remainder making up 100% by weight, wherein the inert gas is nitrogen, helium or argon with a purity of 4N to 9N.

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

4. The thin film forming method according to claim 1, wherein The thin film is made by forming the nitride film, the metal film or a selective thin film thereof on the entire substrate or a part of the substrate.

5. The thin film forming method according to claim 1, wherein The precursor compound is a molecule consisting of one or more molecules selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ta, Co, Ru and Ti, and the vapor pressure of the compound at 25° C. is greater than 0.01 mTorr and less than or equal to 100 Torr.

6. The thin film forming method according to claim 1, wherein include: The step of injecting the precursor compound into the chamber so that it is adsorbed on the surface of the substrate, a step of performing a first purge of the interior of the chamber using a purge gas, injecting the reducing agent into the chamber to reduce the adsorbed precursor compound, and The chamber is purged for the second time using a purge gas.

7. The thin film forming method according to claim 1 or 6, wherein: The thin film forming method further comprises: The step of injecting a nitriding agent or an additional reducing agent into the chamber to form a nitride film.

8. The thin film forming method according to claim 1, wherein The chamber is an atomic layer deposition chamber, a chemical vapor deposition chamber, a plasma enhanced atomic layer deposition chamber or a plasma enhanced chemical vapor deposition chamber.

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

10. 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, characterized in that: The thin film is produced 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 film is a multi-layer structure of two or three layers.

13. A semiconductor device, characterized in that: The semiconductor substrate according to claim 11 is included.

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