Reactive species surface adsorption aid, thin film, semiconductor substrate and semiconductor device

Abstract

The present invention relates to a reactive species surface adsorption aid, a thin film, a semiconductor substrate, and a semiconductor device. According to the present invention, when applied to a substrate before the introduction of a metal precursor, the adsorption energy of the reactive species is reduced when the substrate is exposed to the metal precursor, thereby promoting the nucleation of the reactive species. This achieves both an improvement in the initial growth rate and an improvement in resistivity characteristics, resulting in the provision of a high-quality thin film.

Description

[Technical Field]

[0001] The present invention relates to a reactive species surface adsorption aid, a thin film, a semiconductor substrate, and a semiconductor device. Specifically, it relates to a reactive species surface adsorption aid, a thin film, a semiconductor substrate, and a semiconductor device that are applied to a substrate before the introduction of a metal precursor, and reduce the adsorption energy of the reactive species when the substrate is exposed to the metal precursor, thereby promoting nucleation of the reactive species, and thereby achieving both improved initial growth rate and improved resistivity characteristics, and providing a high-quality thin film. [Background technology]

[0002] Conventionally, in thin film formation by atomic layer deposition (ALD), sufficient adsorption of reactive species derived from the introduced metal precursor onto the substrate surface is a crucial factor at the start of the deposition process.

[0003] The factors determining the initial nucleation time are influenced by the extent to which the reactant species is adsorbed onto the surface.

[0004] As semiconductor devices become smaller, when depositing thin films horizontally, the longer the initial nucleation is delayed, the more additional ALD (Advanced Laser Development) process is required to assist nucleation. This is not only disadvantageous from the perspective of UPH (units per hour), i.e., productivity, but also leads to an increase in the surface roughness and deterioration of the crystallinity of the thin film, resulting in a decrease in the density and electrical conductivity of the thin film.

[0005] Therefore, there is a strong desire to develop a film deposition technology that can accelerate initial nucleation growth with each deposition cycle, thereby increasing the film thickness per cycle without requiring a separate ALD process for initial nucleation. This technology can achieve both improved productivity and improved film quality.

[0006] [Prior art documents] [Patent Documents]

[0007]

[0008] Korean Published Patent Publication No. 2021-0077789 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] The object of the present invention is to provide a reactive species surface adsorption aid that can be applied to a substrate before the introduction of a metal precursor and achieve both increased film thickness and improved resistivity.

[0010] Another object of the present invention is to provide a thin film using the aforementioned reactive species surface adsorption aid and a method for producing the same.

[0011] A further object of the present invention is to provide a semiconductor substrate and a semiconductor device including the thin film. [Means for solving the problem]

[0012] The present invention provides a reactant surface adsorption aid for assisting the surface adsorption of reactants onto a metal precursor for thin films, wherein the reactant surface adsorption aid is an iodine-containing compound.

[0013] The aforementioned reactant surface adsorption aid may be an iodine-containing compound that reduces the adsorption energy of reactants and promotes reactant nucleation when the substrate is exposed to a metal precursor.

[0014] The iodine-containing compound may be one or more selected from hydrogen iodide, hydrogen iodide solution, and a halide having an alkyl group with 4 to 15 carbon atoms.

[0015] The hydrogen iodide or hydrogen iodide aqueous solution is 3N to 15N of hydrogen iodide simple substance, a gas mixture containing 1 wt% to 99 wt% of 3N to 15N hydrogen iodide with the balance being inert gas to make the total amount 100 wt%, or an aqueous solution mixture containing 0.5 wt% to 70 wt% of 3N to 15N hydrogen iodide with the balance being water to make the total amount 100 wt%, wherein the inert gas may be nitrogen, helium or argon having a purity of 4N to 9N.

[0016] The alkyl group having 4 to 15 carbon atoms may be an iodine compound having a secondary benzyl, secondary allyl, tertiary benzyl, tertiary allyl, or tertiary alkyl structure.

[0017] The metal precursor may be one or more selected from the group represented by the following chemical formula (1) to chemical formula (6).

[0018]

Chemical Formula

[0019] (In the above chemical formula (1), x is an integer of 1 to 3, M is selectable from the group consisting of Li, Be, C, P, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Te, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Cs, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, At and Tn, y is an integer of 1 to 6, z is an integer of 0 to 6 (preferably 1 to 6), and L and L' are each independently H, C, N, O, F, P, S, Cl, Br or I, or a ligand composed of one or a combination of two or more selected from the group consisting of H, C, N, O, F, P, S, Cl and Br.)

[0020]

[0021]

Chemical Formula

[0022] (In the above chemical formula (2), M1 is Zr, Hf, Si, Ge, or Ti, X1, X2, and X3 are each independently -NR1R2, -OR3, or R4, R1 to R4 are each independently alkyl groups having 1 to 6 carbon atoms, and n is 1 or 2.)

[0023]

[0024] [ka]

[0025] (In the above chemical formula (3), M is Zr, Hf, Si, Ge, or Ti, R1 is independently hydrogen or an alkyl group having 1 to 4 carbon atoms, n is an integer from 0 to 5, X'1, X'2, and X'3 are independently -NR'1R'2, -OR'3, or R'4, and R'1 to R'4 are independently alkyl groups having 1 to 6 carbon atoms.)

[0026] [ka]

[0027] (In the above chemical formula (4), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo; O is oxygen, X is a halogen, L is a ligand, n is an integer from 0 to 2, m is an integer from 2 to 6, and k is an integer from 0 to 3.)

[0028] [ka]

[0029] (In the above chemical formula (5), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo; X is a halogen element; Y is an amine or alkoxy element; a is an integer from 0 to 6; b is an integer from 0 to 6; Z is selected from the group consisting of alkyl cyanides having 1 to 15 carbon atoms, or linear or cyclic saturated hydrocarbons having 3 to 15 carbon atoms and substituted with one or more nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); c is an integer from 0 to 5.)

[0030] [ka]

[0031] (In the above chemical formula (6), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo, and L1, L2, L3, L4, L5, and L6 are each independently H;F;Cl;Br;I;NR) a R b ;OR c ;CO;R d Cp; amidinates; guanidinates; ethylenediamines; propylenediamines; and linear or cyclic saturated or unsaturated hydrocarbons substituted with one or more carbon (C), nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); one selected from the group, wherein Cp is cyclopentadienyl, and R a , R b , R c and R d Each of these is independently hydrogen or an alkyl group having 1 to 12 carbon atoms, and each of the aforementioned h and I is independently 0 or 1, and the oxidation number of the entire compound is an integer between -2 and 6.

[0032] The thin film may be a laminated film of one or more elements selected from the group consisting of Li, Be, C, P, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Te, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Cs, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, At, and Tn.

[0033] The aforementioned effect becomes more pronounced when the metal constituting the thin film is a hard acid metal with a small size and high affinity for ionic bonding.

[0034] For example, these could be Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Ti, Zr, Hf, Ti, Zr, Hf, V, Nb, Cr, Al, Ga, Si, Ge, Sn, As, Sb.

[0035] The thin film may be a nitride film, a metal film, an oxide film, or a thin film selected from these, formed on all or part of the substrate.

[0036]

[0037] Furthermore, the present invention provides a thin film characterized by being formed by applying the aforementioned reactive species surface adsorption aid before introducing a metal precursor.

[0038] The thin film may be a dielectric film, wiring, or barrier metal.

[0039] The dielectric film may be SiO2, ZrO2, HfO2, TiO2, or Al2O3.

[0040] The wiring may be formed from one or more metals (M) selected from the group consisting of Al, Cu, Au, Mo, Ag, W, Pt, Ag, Ta, Co, Ru, and Ti.

[0041] The barrier metal may be a metal (M), a metal nitride (MN), a metal sulfide (MS2), or a metal carbide (MC), and may be formed from one of the following: TiN, TiC / TiN, TiAlN, TiSiN, TaSiN, WN, WC, TaN, and MoN.

[0042] The aforementioned thin film exhibits a growth rate of 0.1 Å / cycle to 1.5 Å / cycle during the initial film formation phase, where the initial phase can range from 1 cycle to 70 cycles.

[0043] The aforementioned wiring and barrier metal thin film may have resistivity values ​​of 0.1 μΩ·cm to 1,000 μΩ·cm based on a thin film thickness of 50 nm.

[0044] The aforementioned wiring and barrier metal thin film may have resistivity values ​​of 0.1 μΩ·cm to 500 μΩ·cm based on a thin film thickness of 100 nm.

[0045]

[0046] Furthermore, the present invention is

[0047] The steps include: exposing the substrate to the aforementioned surface adsorption aid for reactive species to form a seed layer;

[0048] The steps include: transporting the substrate into the chamber and exposing the seed layer to a metal precursor to form a surface adsorption layer of reactive species;

[0049] The present invention provides a thin film formation method, which includes the step of exposing the aforementioned reactant surface adsorption layer to a reaction gas to form a reactant adsorption layer.

[0050] The thin film formation method may include the steps of: exposing a substrate to the aforementioned reactive species surface adsorption aid to form a seed layer; introducing a metal precursor into a chamber to form a reactive species surface adsorption layer on the substrate; primary purging of the inside of the chamber with a purge gas; exposing the reactive species surface adsorption layer to a reaction gas to form a reactive species adsorption layer; and secondary purging of the inside of the chamber with a purge gas.

[0051] 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.

[0052] The substrate placed inside the chamber can be heated to a temperature of 100°C to 800°C.

[0053] The reaction gas may be a nitriding agent, a reducing agent, or an oxidizing agent.

[0054] The nitriding agent may be nitrogen, ammonia, or the like.

[0055] The reducing agent may be hydrogen or the like.

[0056] The oxidizing agent may be oxygen, ozone, water, N2O, etc.

[0057] Furthermore, the present invention provides a semiconductor substrate characterized by including the aforementioned thin film.

[0058] The thin film may have a multilayer structure consisting of two or three layers.

[0059] Furthermore, the present invention provides a semiconductor device characterized by including the aforementioned semiconductor substrate. [Effects of the Invention]

[0060] The reactive species surface adsorption aid of the present invention reduces the adsorption energy of reactive species and promotes nucleation of reactive species when the substrate is exposed to a metal precursor. This not only increases the film thickness relative to the number of cycles but also reduces leakage current, resulting in a semiconductor device with excellent resistivity characteristics.

[0061] Furthermore, the reactive species surface adsorption aid of the present invention improves the growth rate and increases productivity, while simultaneously improving the film density and electrical conductivity of the metal or metal nitride (MN) or metal carbide (MC) forming the wiring or barrier metal, thereby providing a semiconductor device with extremely superior performance. [Brief explanation of the drawing]

[0062] [Figure 1] This is a schematic cross-sectional diagram showing the difference in thin film formation methods depending on whether or not a reactive species surface adsorption aid is used. (a) shows a thin film formed using a substrate that was not pretreated with a reactive species surface adsorption aid, using the conventional technique described later. (b) shows a thin film formed using Example 1, using a substrate that was pretreated with a reactive species surface adsorption aid.

[0063] [Figure 2] This graph compares the film thickness per cycle of Example 1 of the present invention with that of Comparative Example 1 using the conventional technique. [Modes for carrying out the invention]

[0064]

[0065] The present invention will be described in detail below.

[0066] In this description, the term "reactive species" refers, unless otherwise specified, to substrate adsorbents that can substitute or detach ligands from a metal precursor to form a film.

[0067] In this description, the terms "surface adsorption" or "adsorption" refer to the suitable action of substances other than the metal precursor and reactants on the reaction surface to improve the film quality, such as reducing the resistivity, increasing density, reducing impurities, and improving step coverage of the formed thin film.

[0068]

[0069] The inventors have found that by using a predetermined halogen compound that can reduce the adsorption energy of reactive species and promote nucleation of reactive species when exposing the surface of a substrate introduced into a chamber to a metal precursor, it is possible to increase the film thickness per cycle while improving film quality such as electrical properties, dielectric properties, and thin film density. Based on this finding, the inventors have further researched this area and have completed the present invention.

[0070] As described above, the present invention is characterized by improving the thickness of the thin film per cycle and enhancing the resistivity characteristics by applying a reactive species surface adsorption aid before the introduction of the metal precursor in order to solve the aforementioned problems.

[0071] These characteristics improve the density of the thin film, increase the capacitance in the case of dielectric films (SiO2, ZrO2, HfO2, TiO2, Al2O3, etc.), reduce leakage current, and have a very excellent effect when manufacturing semiconductor devices.

[0072] Furthermore, it has a very excellent effect in manufacturing semiconductor devices by improving the electrical conductivity of the metal (M), metal nitride (MN), or metal carbide (MC) that form the wiring or barrier metal.

[0073] Here, metals include, for example, Li, Be, C, P, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr. , Y, Zr, Nb, Mo, Te, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Cs, Ba, L It may be one or more selected from a, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, At, and Tn, preferably one or more selected from the group consisting of Al, Si, Ti, V, Co, Ni, Cu, Zn, Ga, Ge, Se, Zr, Nb, Mo, Ru, Rh, In, Sn, Sb, Te, Hf, Ta, W, Re, Os, Ir, La, Ce, and Nd.

[0074] The aforementioned thin films may, as specific examples, have a film composition of silicon nitride film, silicon oxide film, titanium nitride film, titanium oxide film, tungsten nitride film, molybdenum metal film, hafnium metal film, zirconium metal film, tungsten metal film, aluminum metal film, molybdenum nitride film, hafnium oxide film, zirconium oxide film, tungsten oxide film, or aluminum oxide film.

[0075] The aforementioned thin film may contain the aforementioned film composition alone or in a selective area, but the present invention is not limited thereto and may also include films having Si-H bonds or Si-OH bonds.

[0076] The thin film can be used not only as a diffusion-blocking film, which is normally used, but also as an etching stop film, electrode film, dielectric film, gate insulating film, block oxide film, or charge trap in semiconductor devices.

[0077]

[0078] The reactive species surface adsorption aid used in the present invention can be an iodine-containing compound, and as an example, it is characterized by using one or more selected from hydrogen iodide, hydrogen iodide solution, and halides having an alkyl group with 4 to 15 carbon atoms. In this case, by using a predetermined halogen compound that can reduce the adsorption energy of reactive species and promote nucleation of reactive species when the substrate surface is exposed to a metal precursor, it is possible to increase the film thickness per cycle while improving film quality such as electrical properties, dielectric properties, and thin film density.

[0079] As a specific example, the surface adsorption aid for the reactive species can be introduced in various forms, such as by itself, as a gas mixture, or as an aqueous solution mixture, before the introduction of the metal precursor.

[0080] As an example of the aforementioned element, 100% by weight of hydrogen iodide (HI) with a strength of 3N to 15N can be used.

[0081] The aforementioned element is an iodine compound having a secondary benzyl, secondary allyl, tertiary benzyl, tertiary allyl, or tertiary alkyl structure with an alkyl group having 4 to 15 carbon atoms, and can be used at 100% by weight.

[0082] The aforementioned gas mixture may, for example, contain 1% to 99% by weight of HI with a purity of 3N to 15N, with the remainder being an inert gas making up 100% by weight of the total. Here, as the inert gas, nitrogen, helium, argon, etc., with a purity of 4N to 9N can be used.

[0083] The aforementioned aqueous solution mixture may, for example, be an aqueous solution mixture containing 0.5% to 70% by weight of HI with a strength of 3N to 15N, with the remainder being H2O, for a total amount of 100% by weight.

[0084]

[0085] In the present invention, a wide variety of substances known in the industry can be used as metal precursors, including substances represented by the following chemical formulas (1) to (6).

[0086] 1) The following chemical formula (1)

[0087]

Chemical Formula

[0088] In the above chemical formula (1), x is an integer of 1 to 3, M can be selected from the group consisting of Li, Be, C, P, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Te, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Cs, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, At and Tn, y is an integer of 1 to 6, z is an integer of 0 to 6 (preferably 1 to 6), and L and L' are each independently H, C, N, O, F, P, S, Cl, Br or I, or a ligand composed of one or a combination of two or more selected from the group consisting of H, C, N, O, F, P, S, Cl and Br.

[0089] For example, the substance represented by the above chemical formula (1) may be SiH₂Cl₂, SiH₂I₂, or the like.

[0090] 2) The following chemical formula (2)

[0091]

Chemical Formula

[0092] In the above chemical formula (2), M₁ is Zr, Hf, Si, Ge or Ti, and X₁, X₂ and X₃ are each independently -NR₁R 2、 -OR 3、 or R₄, R₁ to R₄ are each independently an alkyl group having 1 to 6 carbon atoms, and n is 1 or 2.

[0093] 3) The following chemical formula (3)

[0094] [ka]

[0095] In the above chemical formula (3), M is Zr, Hf, Si, Ge, or Ti, R1 is independently hydrogen, an alkyl group having 1 to 4 carbon atoms, n is an integer from 0 to 5, X'1, X'2, and X'3 are independently -NR'1R'2, -OR'3, or R'4, and R'1 to R'4 are independently alkyl groups having 1 to 6 carbon atoms.

[0096] 4) The following chemical formula (4)

[0097] [ka] In the above chemical formula (4), Mo is molybdenum, O is oxygen, X is a halogen, L is a ligand, n is an integer from 0 to 2, m is an integer from 2 to 6, and k is an integer from 0 to 3.

[0098] 5) The following chemical formula (5)

[0099] [ka]

[0100] (In the above chemical formula (5), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo; X is a halogen element; Y is an amine or alkoxy element; a is an integer from 0 to 6; b is an integer from 0 to 6; Z is selected from the group consisting of alkyl cyanides having 1 to 15 carbon atoms, or linear or cyclic saturated hydrocarbons having 3 to 15 carbon atoms and substituted with one or more nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); c is an integer from 0 to 5.)

[0101] 6) The following chemical formula (6)

[0102] [ka]

[0103] In the above chemical formula (6), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo, and L1, L2, L3, L4, L5, and L6 are each independently H;F;Cl;Br;I;NR a R b ;OR c ;CO;R d Cp; amidinates; guanidinates; ethylenediamines; propylenediamines; and linear or cyclic saturated or unsaturated hydrocarbons substituted with one or more carbon (C), nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); one selected from the group, wherein Cp is cyclopentadienyl, and R a , R b , R c and R d Each of these is independently hydrogen or an alkyl group having 1 to 12 carbon atoms, and each of the aforementioned h and I is independently 0 or 1, and the oxidation number of the entire compound is an integer from -2 to 6.

[0104] To give a specific example, the ligand may be a thin-film metal precursor selected from the group consisting of alkyl cyanides having 1 to 15 C12 alkyl groups, and linear or cyclic saturated hydrocarbons having 3 to 15 C12 and substituted with one or more nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S).

[0105] The reaction gas used in this invention can be selected according to the target thin film to be manufactured, and examples linked to the target thin film are as follows.

[0106] The reaction gas for the oxide film can be selected from one or more of the following: O2, O3, H2O, and N2O.

[0107] Furthermore, one or more reaction gases for metal films can be selected from H2, NH3, and reducing molecules (such as formic acid).

[0108] Furthermore, the reaction gas for the nitride film may be NH3 or an H2 / N2 gas mixture.

[0109] Furthermore, the reaction gas for the metal carbide film is H2, an alkane, or M(CH3)3, where M may be a boron group (group 13 of the periodic table) element.

[0110] Furthermore, the reaction gas for the metal sulfide film may be molecular species in the gaseous or vapor phase containing H2S and S.

[0111] As a specific example, the TiN nitride film of a semiconductor device fabricated according to the present invention has an initial growth rate (growth rate per cycle (GPC)) up to 70 cycles, for example, 0.1 Å / cycle to 1.5 Å / cycle, preferably 0.5 Å / cycle to 1.5 Å / cycle, and more preferably 0.8 Å / cycle to 1.2 Å / cycle. In this case, improving the initial growth rate exhibits the effect of increasing the film thickness per cycle.

[0112] The TiN nitride film of the semiconductor device fabricated according to the present invention has a resistivity value based on a thin film thickness of 50 nm, for example, 0.1 μΩ·cm to 1,000 μΩ·cm, preferably 15 μΩ·cm to 590 μΩ·cm, and more preferably 15 μΩ·cm to 290 μΩ·cm. Within this range, it exhibits the effect of obtaining excellent thin film properties.

[0113] As an example, the resistivity of the thin film, based on a film thickness of 100 nm, may range from 0.1 μΩ·cm to 500 μΩ·cm, preferably from 15 μΩ·cm to 120 μΩ·cm. Within this range, the effect of obtaining excellent thin film properties is achieved.

[0114]

[0115] On the other hand, the surface adsorption aid for reactive species can form a seed layer on the substrate.

[0116] As an example, the seed layer may be formed on all or part of the substrate on which the thin film is formed.

[0117] The seed layer is characterized by not remaining in the thin film.

[0118] In this context, "no residue" means, unless otherwise specified, the presence of C, Si, N, and halogen elements at concentrations of less than 0.1 atoms (atom%) when performing component analysis by X-ray photoelectron spectroscopy (XPS). More preferably, in a secondary ion mass spectrometry (SIMS) or X-ray photoelectron spectroscopy (XPS) measurement method that performs measurements while drilling into the substrate in the depth direction, it is preferable that the increase or decrease in the signal intensity of each element species does not exceed 5% when considering the increase or decrease in C, N, Si, and halogen impurities before and after the use of the auxiliary agent under the same film formation conditions.

[0119] The thin film may, for example, contain a halogen compound at a concentration of 100 ppm or less.

[0120] The thin film can be used as an etching stop film, electrode film, dielectric film, gate insulating film, block oxide film, or charge trap, and the present invention is not limited thereto.

[0121] The surface adsorption aid for the reactive species is preferably a compound with a purity of 99.9% or higher, a compound with a purity of 99.95% or higher, or a compound with a purity of 99.99% or higher. For reference, if a compound with a purity of less than 99% is used, there is a risk that impurities may remain in the thin film or that side reactions with precursors or reactants may occur, so it is preferable to use a substance with a purity of 99% or higher whenever possible.

[0122]

[0123] The present invention provides a thin film formation method that includes the steps of: exposing a substrate to the aforementioned reactive species surface adsorption aid to form a seed layer; transporting the substrate into a chamber and exposing the seed layer to a metal precursor to form a reactive species surface adsorption layer; and exposing the reactive species surface adsorption layer to a reaction gas to form a reactive species adsorption layer. In this case, by reducing the adsorption energy of the reactive species when the substrate is exposed to the metal precursor and promoting the nucleation of the reactive species, it is possible to achieve both an improvement in the initial growth rate and an improvement in the resistivity characteristics, thereby providing a high-quality thin film.

[0124]

[0125] Furthermore, the present invention is

[0126] i) A step of loading the substrate into the chamber and exposing it to a surface adsorption aid for reactive species to form a seed layer on the surface of the substrate,

[0127] ii) A step of primary purging the inside of the chamber with a purge gas,

[0128] iii) A step of vaporizing the metal precursor and exposing the seed layer to the metal precursor to form a surface adsorption layer of reactive species,

[0129] iv) The step of secondary purging the inside of the chamber with a purge gas,

[0130] v) A step of supplying a reaction gas into the chamber to expose the surface adsorption layer of the reactive species and to form the reactive species adsorption layer,

[0131] vi) A thin film formation method is provided, which includes the step of tertiarily purging the inside of the chamber with a purge gas.

[0132]

[0133] The aforementioned metal precursor is a molecule in which the aforementioned metal is the central metal, and may be a precursor whose vapor pressure at 25°C is greater than 0.01 mTorr and less than or equal to 100 Torr.

[0134] In the thin film formation method of the present invention, as a preferred example, the reactive species surface adsorption aid of the present invention may be introduced and adsorbed onto the substrate before the metal precursor within one cycle. In this case, the energy at which the reactive species of the metal precursor are adsorbed is reduced, promoting the nucleation of the reactive species. This achieves both an improvement in the initial growth rate and an improvement in resistivity, thereby providing a high-quality thin film.

[0135]

[0136] As an example, in the thin film formation method, when pretreatment is performed before film formation of the metal precursor using the surface adsorption aid for the reactive species, the unit cycle can be repeated 1 to 99,999 times as needed, preferably 10 to 10,000 times, more preferably 50 to 5,000 times, and even more preferably 100 to 2,000 times. Within this range, the desired thin film thickness can be obtained while fully achieving the effects to be achieved in the present invention.

[0137] 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.

[0138] The aforementioned metal precursor may undergo a step of plasma post-treatment after being vaporized and introduced.

[0139] The amount of purge gas introduced into the chamber in step vi) can be 10 to 100,000 times the volume of the introduced metal precursor and reaction gas.

[0140] The reaction gas and metal precursor can be introduced into the chamber by a VFC (Vapor Flow Control), DLI (Direct Liquid Injection), or LDS (Liquid Supply System) method.

[0141] The substrate introduced into the chamber is heated to 100°C to 800°C, and the ratio of the amount (mg / cycle) of the surface adsorption aid for the reactive species to the metal precursor introduced into the chamber can be 1:1 to 1:20 or 20:1.

[0142] The metal precursor can preferably be introduced into the ALD chamber by a vapor flow control (VFC), direct liquid injection (DLI), or liquid delivery system (LDS) method, and more preferably by an LDS (liquid delivery system) method.

[0143] The substrate introduced into the chamber may be heated to, for example, 100°C to 800°C, and more specifically, 200°C to 600°C. The metal precursor may be introduced onto the substrate either in an unheated state or in a heated state. Depending on the film deposition efficiency, the metal precursor may be introduced in an unheated state first, and then the heating conditions may be adjusted during the film deposition process. For example, it may be introduced onto the substrate in 1 to 20 seconds under temperature conditions of 200°C to 600°C.

[0144]

[0145] The ratio of the amount (mg / cycle) of the metal precursor to the reactant surface adsorption aid introduced into the chamber is preferably 1:1.5 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, there is a significant improvement in the film thickness and resistivity characteristics of the thin film per cycle.

[0146] In this description, the purging period may preferably be 1,000 sccm to 50,000 sccm (Standard Cubic Centimeters per Minute), more preferably 2,000 sccm to 30,000 sccm, and even more preferably 2,500 sccm to 15,000 sccm. Within this range, the thin film growth rate per cycle is appropriately controlled, and the film is deposited as a single atomic layer (atomic mono-layer) or approximately thereto, which is advantageous in terms of film quality.

[0147]

[0148] The aforementioned ALD (atomic layer deposition) process is highly advantageous for the fabrication of integrated circuits (ICs) that require a high aspect ratio. In particular, its self-limiting thin-film growth mechanism offers advantages such as excellent conformality, uniformity, and high-precision thickness control.

[0149] The thin film formation method described above can, for example, be carried out under film formation temperature conditions in the range of 50°C to 800°C, preferably in the range of 200°C to 600°C, more preferably in the range of 350°C to 600°C, even more preferably in the range of 400°C to 600°C, and even more preferably in the range of 450°C to 600°C. Within this range, the effect of growing a thin film with excellent film quality while achieving the ALD process characteristics can be realized.

[0150] The aforementioned thin film formation method can, for example, be carried out under deposition pressure conditions 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 1 Torr to 7 Torr. Within this range, the effect of obtaining a thin film with a uniform thickness can be achieved.

[0151] In this description, the deposition temperature and deposition pressure may be measured under the temperature and pressure conditions formed within the deposition chamber, or under the temperature and pressure conditions applied to the substrate within the deposition chamber.

[0152] The thin film formation method may preferably include the steps of raising the temperature inside the chamber to the film formation temperature before introducing the metal precursor into the chamber and / or purging the chamber by introducing an inert gas before introducing the metal precursor into the chamber.

[0153] Furthermore, the present invention may include a thin film manufacturing apparatus capable of realizing the thin film manufacturing method, comprising: an ALD chamber; a first vaporizer for vaporizing a metal precursor; and a first conveying means for conveying the vaporized metal precursor into the ALD chamber. Here, the vaporizer and the conveying means are not particularly limited, as long as they are vaporizers and conveying means commonly used in the art to which the present invention belongs.

[0154]

[0155] As a specific example, the thin film formation method described above involves first positioning a substrate on which a thin film is to be formed in a film formation chamber capable of depositing atomic layers.

[0156] The substrate may include semiconductor substrates such as silicon substrates and silicon oxide substrates.

[0157] The aforementioned substrate may also have a conductive layer or an insulating layer further formed on its upper surface.

[0158] In particular, the substrate is pre-treated with the aforementioned reactive species surface adsorption aid to form a seed layer.

[0159] In this description, the step of forming a seed layer on the substrate with a reactive species surface adsorption aid can be carried out by supplying the reactive species surface adsorption aid.

[0160] To deposit a surface adsorption layer of reactive species on a substrate positioned in a film deposition chamber, the above-mentioned metal precursor, or a mixture thereof with a nonpolar solvent, is prepared.

[0161] After injecting the prepared metal precursor or a mixture thereof with a nonpolar solvent (thin film formation composition) into the vaporizer, it is converted into a vapor phase and transferred to the film formation chamber where it is adsorbed onto the substrate, and any unadsorbed metal precursor is purged.

[0162] In this description, as a method for transferring metal precursors and the like to the film deposition chamber, one example that can be used is a method that transports volatile gas using a gas phase mass flow controller (MFC) method (Vapor Flow Control; VFC) or a method that transports liquid using a liquid phase mass flow controller (LMFC) method (Liquid Delivery System; LDS). Preferably, the LDS (Liquid Delivery System) method is used.

[0163] In this case, one or more mixed gases selected from the group consisting of argon (Ar), nitrogen (N2), and helium (He) can be used as a carrier gas or diluent gas for moving metal precursors onto the substrate, but the present invention is not limited thereto.

[0164] In this description, as an example of a purge gas, an inert gas can be used, and preferably, the carrier gas or diluent gas can be used.

[0165]

[0166] Next, a reaction gas is supplied. The reaction gas is not particularly limited, and may preferably include a nitride agent, an oxidizing agent, a reducing agent, etc., as long as it is a reaction gas commonly used in the art to which the present invention belongs.

[0167] As an example, a nitride film is formed when a nitride agent reacts with a metal precursor adsorbed on the substrate. The nitride agent used in this process may be nitrogen gas (N2), hydrazine gas (N2H4), or a mixture of nitrogen gas and hydrogen gas.

[0168] Next, an inert gas is used to purge the unreacted residual reaction gas. This removes not only the excess reaction gas but also the by-products that have been generated.

[0169] As described above, the thin film formation method, as an example, can be performed as a unit cycle comprising the steps of: forming a seed layer by pre-treating the substrate with a reaction species surface adsorption aid; transporting the substrate into a chamber and adsorbing a metal precursor onto the substrate; purging the unadsorbed metal precursor; supplying a reaction gas; and purging the residual reaction gas, and the unit cycle can be repeated to form a thin film of a desired thickness.

[0170] As another example, the thin film formation method may consist of the steps of: pre-treating a substrate with a reaction species surface adsorption aid to form a seed layer; transporting the substrate into a chamber and purging the inside of the chamber; adsorbing a metal precursor onto the substrate; purging any unadsorbed metal precursors; supplying a reaction gas; and purging any residual reaction gases, with each unit cycle being repeated to form a thin film of a desired thickness.

[0171] The aforementioned 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 achieved.

[0172]

[0173] Furthermore, the present invention provides a semiconductor substrate, characterized in that the semiconductor substrate is manufactured by the thin film formation method described herein, and in such a case, the effect is obtained of excellent thin film thickness per cycle, in particular, the initial growth rate of the thin film, the density of the thin film, and the electrical properties.

[0174] Preferably, the manufactured thin film has a thickness of 100 nm or less, a resistivity value of 0.1 μΩ·cm to 1,000 μΩ·cm based on a 50 nm film thickness, a resistivity value of 0.1 μΩ·cm to 500 μΩ·cm based on a 100 nm film thickness, a halogen content of 10,000 ppm or less, and a step coverage ratio of 90% or more. Within this range, it exhibits excellent performance as a diffusion-blocking film and reduces corrosion of metal wiring materials, but the present invention is not limited in any way thereto.

[0175] The thin film may have a thickness of, for example, 0.1 nm to 100 nm, preferably 0.5 nm to 50 nm, more preferably 1.5 nm to 10 nm, and even more preferably 2 nm to 5 nm. Within this range, it exhibits the effect of obtaining excellent thin film properties.

[0176] As an example, the aforementioned thin film may have a resistivity of 0.1 μΩ·cm to 1,000 μΩ·cm based on a film thickness of 50 nm, preferably 0.1 μΩ·cm to 560 μΩ·cm, and more preferably 0.1 μΩ·cm to 260 μΩ·cm. Within this range, it exhibits the effect of obtaining excellent thin film properties.

[0177] As an example, the aforementioned thin film may have a resistivity of 0.1 μΩ·cm to 500 μΩ·cm based on a film thickness of 100 nm, preferably 0.1 μΩ·cm to 320 μΩ·cm, and more preferably 0.1 μΩ·cm to 120 μΩ·cm. Within this range, it exhibits the effect of obtaining excellent thin film properties.

[0178] The thin film may preferably have a halogen content of 10,000 ppm or less or 1 to 9,000 ppm, more preferably 5 ppm to 8,500 ppm, and even more preferably 100 ppm to 1,000 ppm. Within this range, excellent thin film properties can be obtained while reducing the growth rate of the thin film. Here, the halogen remaining in the thin film may, for example, be Cl2, Cl, or Cl - This is possible, and the lower the residual amount of halogen in the thin film, the better the film quality, which is therefore preferable.

[0179] The thin film may, for example, have a step coverage ratio of 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, offering the advantage of being usable in next-generation semiconductor devices.

[0180]

[0181] The thin film may, as an example, have a two- or three-layer multilayer structure as needed. The two-layer multilayer film may, as a specific example, have a lower layer-middle layer structure, and the three-layer multilayer film may, as a specific example, have a lower layer-middle layer-top layer structure.

[0182] The aforementioned underlayer film may, for example, consist of one or more elements selected from the group consisting of Si, SiO2, MgO, Al2O3, CaO, ZrSiO4, ZrO2, HfSiO4, Y2O3, HfO2, LaLuO2, Si3N4, SrO, La2O3, Ta2O5, BaO, and TiO2.

[0183] The aforementioned intermediate layer is, as an example, Ti x N y Preferably, it may include TN.

[0184] The aforementioned upper layer may, for example, consist of one or more elements selected from the group consisting of W and Mo.

[0185]

[0186] Furthermore, the present invention provides a semiconductor substrate characterized by being manufactured by the thin-film formation method described above.

[0187] The thin film may have a multilayer structure consisting of two or three layers.

[0188]

[0189] Furthermore, the present invention provides a semiconductor device including the aforementioned semiconductor substrate.

[0190] The semiconductor substrate may be a low-resistive metal gate interconnect, a high-aspect-ratio 3D metal-insulator-metaL capacitor, a dynamic random-access memory (DRAM) trench capacitor, a 3D gate-all-around (GAA) capacitor, or a 3D NAND flash memory.

[0191]

[0192] The following examples and drawings are provided to further the understanding of the present invention. However, these examples and drawings are merely illustrative of the present invention, and it will be obvious to those skilled in the art that a wide variety of changes and modifications can be made within the scope of the present invention and the technical concept. It goes without saying that such modifications and changes also fall within the scope of the attached claims.

[0193] Examples

[0194] Example 1

[0195] A substrate with a 100 nm thick SiO2 film was prepared. 5N HI was prepared as the surface adsorption aid for reactive species, and TiCl4 was prepared as the precursor compound. The ALD process was carried out using the substrate, the surface adsorption aid for reactive species, and the precursor compound.

[0196] Specifically, after the substrate was brought into the film deposition chamber, the prepared reactive species surface adsorption aid was supplied onto the substrate at a flow rate of 100 sccm for 5 seconds.

[0197] Next, the prepared precursor compound was placed in a separate canister and supplied at room temperature to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC). After introducing the vaporized TiCl4 into the deposition chamber for 2 seconds, argon gas was supplied at a flow rate of 5000 sccm for 6 seconds to perform argon purging. At this time, the pressure inside the chamber was controlled to 2.5 Torr.

[0198] During the film deposition reaction, the temperature inside the chamber was maintained at 500°C.

[0199] This process was repeated up to 250 times to form a thin film created by self-limiting atomic layer growth.

[0200] A schematic representation of the manufactured thin film (Ti nitride film) is shown in Figure 1.

[0201] Figure 1 below is a schematic cross-sectional diagram showing the difference in thin film formation methods depending on whether or not a reactive species surface adsorption aid is used. (a) shows a thin film formed using a substrate that was not pretreated with a reactive species surface adsorption aid, using the conventional technique described later. (b) shows a thin film formed using Example 1, using a substrate that was pretreated with a reactive species surface adsorption aid.

[0202] As shown in Figure 1 below, it was found that there is a difference in the promotion of nucleation of reactive species depending on whether or not a reactive species surface adsorption aid is used, and this difference was confirmed by the following test example.

[0203]

[0204] Example 2

[0205] For the substrate, we prepared a substrate with a TiN (20nm) / SiO2 (100nm) film deposited on it.

[0206] 5N HI was prepared as a surface adsorption aid for reactive species.

[0207] Tris(dimethylamide)cyclopentadienylhafnium (CpHf) and tris(dimethylamide)cyclopentadienylzirconium (CpZr) were prepared as precursor compounds.

[0208] Using the aforementioned substrate, a surface adsorption aid for reactive species, and a precursor compound, an ALD process was performed on HfO2 and ZrO2. Then, an Al electrode with a film thickness of 300 nm was formed as the upper electrode by electron beam evaporation, and a MIM (metal-insulator-metal) device was fabricated.

[0209] Specifically, after the substrate was brought into the film deposition chamber, the prepared reactive species surface adsorption aid was supplied onto the substrate at a flow rate of 100 sccm for 5 seconds.

[0210] Next, the prepared precursor compound CpHf was placed in a separate canister and supplied at room temperature to a separate vaporizer heated to 170°C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC). After introducing the vaporized CpHf into the deposition chamber for 3 seconds, argon gas was supplied at a flow rate of 2000 sccm for 6 seconds to perform argon purging. At this time, the pressure inside the chamber was controlled to 1.5 Torr.

[0211] During the film deposition reaction, the temperature inside the chamber was maintained at 300°C.

[0212] This ALD process was carried out until a film thickness of 5 nm was formed.

[0213] Next, the prepared precursor compound CpZr was placed in a separate canister and supplied at room temperature to a separate vaporizer heated to 170°C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC). After introducing the vaporized CpZr into the film deposition chamber for 3 seconds, argon gas was supplied at a flow rate of 2000 sccm for 6 seconds to perform argon purging. At this time, the pressure inside the chamber was controlled to 1.5 Torr.

[0214] A pattern was formed using a photolithography process, and the underlying Si was exposed by a dry etching process. Dry etching was performed under the following conditions. • Source / Bias Power: 350 / 100W • CF4 / Ar gas flow rate: 80 / 20 sccm • Process pressure: 5 mTorr Etching time: 45 seconds Furthermore, Figure 3 shows the MIM element manufactured after forming the upper electrode at 300 nm using electron beam evaporation (electrode area: 200 μm × 200 μm).

[0215] The differences in electrical characteristics depending on whether or not a reactive species surface adsorption aid was used were confirmed by measuring current-voltage characteristics (IV) and capacitance-voltage characteristics (CV).

[0216] *IV measurement of MIM element: Leakage current and breakdown voltage values ​​were compared by measuring the voltage within the range of 0V to 15V.

[0217] *CV measurement of MIM elements: Measurements were performed under the conditions of frequency: 1MHz, voltage amplitude: 100mm, and voltage range: -2V to 2V, and the values ​​of charge capacitance and dielectric constant were compared.

[0218] Based on the CV measurement results, the charge capacitance (electrostatic capacitance) and dielectric constant were derived using the following equation 1.

[0219]

number

[0220]

[0221] (In the above formula, ε r is the relative permittivity, C ox (where ε0 is the capacitance, ε0 is the dielectric constant in vacuum, A is the area of ​​the plates, d is the distance between the plates, and F is the force acting on the conducting plate.)

[0222]

[0223] Example 3

[0224] The ALD process was carried out using 5N HI as the surface adsorption aid for the reactive species, NH3 as the reducing agent, and the BTBMMo precursor compound with the following chemical formula as the precursor compound.

[0225] [Chemical formula]

[0226] [ka]

[0227] First, the substrate was placed into the film deposition chamber, and then the prepared reactive species surface adsorption aid was supplied onto the substrate at a flow rate of 100 sccm for 5 seconds.

[0228] Next, the prepared precursor compound was placed in a separate canister and supplied at room temperature to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC). After the BTBMMo precursor vaporized into a vapor phase in the vaporizer was introduced into the film deposition chamber for 3 seconds, argon gas was supplied at a flow rate of 3000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the chamber was controlled to 2.5 Torr.

[0229] Next, NH3 as a reducing agent was supplied to the chamber at a flow rate of 1000 sccm, followed by argon purging by supplying argon gas at a flow rate of 3000 sccm for 10 seconds. During this time, the pressure inside the chamber was controlled to 2.5 Torr. The deposition temperature was maintained at 350°C, and this process was repeated 200 to 400 times to form a thin film with a thickness of 10 nm, which was created by self-limiting atomic layer growth.

[0230] An ellipsometer, a device capable of measuring optical properties such as film thickness and refractive index of a fabricated thin film (MoN metal film) using the polarization characteristics of light, was used to measure the film thickness. The film thickness per cycle was calculated by dividing the measured thickness by the number of cycles, and the result was 10 nm. The thin film was analyzed for its components using Auger electron spectroscopy (AES) and SIMS analysis. Then, the surface resistance was measured using a four-probe method, and the resistivity was calculated using the measured film thickness.

[0231]

[0232] Comparative Example 1

[0233] The same process as in Example 1 was repeated, except that in Example 1, a step was not performed in which pretreatment with a reactant surface adsorption aid was not applied.

[0234]

[0235] Comparative Example 2

[0236] A thin film was prepared using the same procedure as in Example 2, except that the step of not pre-treating with a reactant surface adsorption aid was not used in Example 2.

[0237]

[0238] Comparative Example 3

[0239] The same procedure as in Example 3 was repeated, except that in Example 3, a step was not performed in which pretreatment with a reactant surface adsorption aid was not applied.

[0240]

[0241] <Test Example 1: Comparison of Thin Film Thickness per Cycle>

[0242] For each of the thin films obtained in Example 1 and Comparative Example 1, the film thickness was calculated using the ellipsometer method, which is an optical thickness measurement method.

[0243] Specifically, the film thickness of a thin film measured using an ellipsometer, a device capable of measuring optical properties such as film thickness and refractive index using the polarization characteristics of light, is divided by the number of cycles to calculate the film thickness deposited per cycle, and the resulting values ​​are shown in Figure 2 below.

[0244] Figure 2 below is a graph comparing the film thickness per cycle of Example 1 of the present invention and Comparative Example 1 using the conventional technique.

[0245] As shown in Figure 2 below, in Example 1, which used a step of pretreatment with a reactive species surface adsorption aid, it was confirmed that thin film growth was promoted in the early stages of film formation at 70 cycles. In contrast, in Comparative Example 1, which used a step of not pretreatment with a reactive species surface adsorption aid, the thickness of the thin film was hardly observed until almost 50 cycles.

[0246] These results confirm that using a pretreatment step with a surface adsorption aid for reactive species has the effect of increasing the film thickness per cycle.

[0247]

[0248] <Test Example 2: Comparison of Resistivity>

[0249] For each of the thin films obtained in Example 1 and Comparative Example 1, the resistance was evaluated by converting the results obtained by the 4-probe measurement method to resistivity using the film thickness value, and the results are shown in Table 1 below.

[0250] [Table 1]

[0251] As shown in Table 1 above, compared to Comparative Example 1, which used a process without pretreatment with a reactive species surface adsorption aid, Example 1, which used a process with pretreatment with a reactive species surface adsorption aid, showed improved resistivity values ​​for each film thickness.

[0252] <Test Example 3: Comparison of Breakdown Voltage and Dielectric Constant>

[0253] The results obtained for each thin film of Example 2 and Comparative Example 2 using the IV (current-voltage) and CV (capacitance-voltage) measurement methods are shown in Table 2 below.

[0254] [Table 2]

[0255] As shown in Table 2 above, compared with Comparative Example 2 using the step without pretreatment with the reactive species surface adsorption auxiliary agent, it was confirmed that in Example 2 using the step of performing pretreatment with the reactive species surface adsorption auxiliary agent, the dielectric constant was improved by 20% or more, and the breakdown voltage was also improved by about 0.46 MV / cm. As a result, it was confirmed that Example 2 using the step of performing pretreatment with the reactive species surface adsorption auxiliary agent according to the present invention had improved density of the thin film and improved crystallinity, and electrical characteristics such as the dielectric constant were significantly enhanced, as compared with Comparative Example 2.

[0256]

[0257] <Test Example 4: Impurity Reduction Characteristics>

[0258] Impurities in the thin film were analyzed using Auger electron spectroscopy (AES).

[0259] Specifically, a focused electron beam was incident on the surface of the material, the energy of Auger electrons emitted was measured, and the types and contents of elements constituting the surface of the material were analyzed.

[0260] [Table 3]

[0261] As shown in Table 3 above, in Example 3 according to the present invention, it was confirmed from the AES analysis results that C impurities were reduced to 0% during thin film formation, and according to the SIMS results, it was confirmed that the number of C ions detected decreased by 91% or more. Furthermore, since the density of the thin film increased from 6.0 to 6.8, it can be seen that a very high-quality MoN thin film was formed.

[0262]

[0263] In conclusion, Example 1, which used a step of pretreatment with the reactive species surface adsorption aid according to the present invention, showed a significant improvement in the initial growth rate and increased film thickness per cycle compared to Comparative Example 1, which did not undergo such pretreatment. It was also confirmed that an excellent improvement in resistivity characteristics was obtained. Therefore, it was confirmed that by adopting a predetermined reactive species surface adsorption aid as a pretreatment agent in the ALD process cycle according to the present invention, it is possible to increase the film thickness and improve the film quality, thereby providing a thin film required for semiconductor devices that require improved resistivity.

Claims

1. A reactant surface adsorption aid that assists the surface adsorption of reactants to a metal precursor for thin films, The aforementioned surface adsorption aid for reactive species is characterized by being an iodine-containing compound.

2. The reactant surface adsorption aid according to claim 1, characterized in that the reactant surface adsorption aid is an iodine-containing compound that reduces the adsorption energy of reactants and promotes reactant nucleation when the substrate is exposed to a metal precursor.

3. The surface adsorption aid for reactive species according to claim 1, characterized in that the iodine-containing compound is one or more selected from hydrogen iodide, hydrogen iodide solution, and a halide having an alkyl group with 4 to 15 carbon atoms.

4. The surface adsorption aid for reactive species according to claim 3, characterized in that the C4-C15 alkyl group is an iodine compound having a secondary benzyl, secondary allyl, tertiary benzyl, tertiary allyl, or tertiary alkyl structure.

5. The surface adsorption aid for reactive species according to claim 1, characterized in that the metal precursor is one or more selected from the group represented by the following chemical formulas (1) to (6): 【Chemistry 1】 (In the above chemical formula (1), x is an integer from 1 to 3, and M is Li, Be, C, P, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Te, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Cs, Ba, La, H) The group consisting of f, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, Pt, At, and Tn can be selected, y is an integer from 1 to 6, z is an integer from 0 to 6 (preferably from 1 to 6), and L and L' are each independently H, C, N, O, F, P, S, Cl, Br, or I, or ligands consisting of one or more selected from the group consisting of H, C, N, O, F, P, S, Cl, and Br. 【Chemistry 2】 (In the above chemical formula (2), the aforementioned M １ is Zr, Hf, Si, Ge or Ti, and the aforementioned X １ , X ２ , X ３ are each independently, -NR １ R ２、 -OR ３ or R ４ , and the aforementioned R １ to R ４ are each independently an alkyl group having 1 to 6 carbon atoms, and the aforementioned n is 1 or 2.) 【Transformation 3】 (In the above chemical formula (3), M is Zr, Hf, Si, Ge, or Ti, and R １ Each of these is independently a hydrogen atom and an alkyl group having 1 to 4 carbon atoms, and the n is an integer from 0 to 5, and X' １ , X' ２ and X' ３ These are, independently, -NR' １ R' ２ , -OR' ３ , or R' ４ R' １ ~R' ４ Each of these is an alkyl group having 1 to 6 carbon atoms. 【Chemistry 4】 (In the above chemical formula (4), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo; O is oxygen, X is a halogen, L is a ligand, n is an integer from 0 to 2, m is an integer from 2 to 6, and k is an integer from 0 to 3.) 【Transformation 5】 (In the above chemical formula (5), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu, and Mo; X is a halogen element; Y is an amine or alkoxy element; a is an integer from 1 to 6; Z is selected from the group consisting of alkyl cyanides having 1 to 15 carbon atoms, or linear or cyclic saturated hydrocarbons having 3 to 15 carbon atoms and substituted with one or more nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); b is an integer from 0 to 5.) 【Transformation 6】 (In the above chemical formula (6), M is one or more selected from the group consisting of Co, Ni, Ru, Ti, Ta, Nb, W, Cu and Mo, and L １ , L ２ , L ３ , L ４ , L ５ and L ６ These are H; F; Cl; Br; I; NR, each independently. ａ R ｂ OR ｃ ;CO;R ｄ Cp; amidinate; guanidinate; ethylenediamine; propylenediamine; and linear or cyclic saturated or unsaturated hydrocarbons substituted with one or more carbon (C), nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S); is selected from the group, wherein Cp is cyclopentadienyl, and R ａ , R ｂ , R ｃ and R ｄ Each of these is independently hydrogen or an alkyl group having 1 to 12 carbon atoms, and each of h and I is independently 0 or 1, and the oxidation number of the entire compound is an integer from -2 to 6.

6. The surface adsorption aid for reactive species according to claim 1, characterized in that the thin film is a laminated film of one or more types selected from the group consisting of Li, Be, C, P, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Te, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Cs, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, At, and Tn.

7. The surface adsorption aid for reactive species according to claim 1, characterized in that the thin film is a nitride film, a metal film, an oxide film, or a thin film selected therefrom, formed on all or part of the substrate.

8. A thin film characterized by being formed by applying the reactant surface adsorption aid described in claim 1 before introducing a metal precursor.

9. The thin film according to claim 8, characterized in that the thin film is a dielectric film, wiring, or barrier metal.

10. The thin film according to claim 8, characterized in that the thin film exhibits an initial growth rate of 0.1 Å / cycle to 1.5 Å / cycle, where the initial growth rate is 1 cycle to 70 cycles.

11. The thin film according to claim 8, characterized in that the thin film has a resistivity of 0.1 μΩ·cm to 1,000 μΩ·cm based on a film thickness of 50 nm, and a resistivity of 0.1 μΩ·cm to 500 μΩ·cm based on a film thickness of 100 nm.

12. The steps include: exposing the substrate to the reactive species surface adsorption aid described in claim 3 to form a seed layer; The steps include: transporting the substrate into the chamber and exposing the seed layer to a metal precursor to form a surface adsorption layer of reactive species; The steps include: exposing the surface adsorption layer of the reactants to a reaction gas to form a reactants adsorption layer; A method for forming a thin film, characterized by including the following:

13. A semiconductor substrate characterized by comprising the thin film described in claim 8.

14. A semiconductor device characterized by including the semiconductor substrate described in claim 13.

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