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

Abstract

The present invention relates to a method for forming a thin film, and a semiconductor substrate and a semiconductor device manufactured thereby. The present invention has the effect of improving the reaction rate by effectively replacing the ligand of an adsorbed precursor by using a reaction surface pretreatment agent in combination with a ligand replacement agent, and by appropriately lowering the thin film growth rate, even when a thin film is formed on a substrate having a complex structure, significantly improving step coverage and thin film thickness uniformity, and reducing impurities to improve film quality.

Description

[Technical field]

[0001] The present invention relates to a thin film formation method, and a semiconductor substrate and a semiconductor device manufactured thereby. More specifically, the present invention relates to a thin film formation method that can significantly improve step coverage and film thickness uniformity of a thin film even when a thin film is formed on a substrate having a complex structure by sequentially applying a reaction surface pretreatment agent and a ligand replacement agent with a precursor compound, thereby significantly reducing impurities and improving film quality, and a semiconductor substrate and a semiconductor device manufactured thereby. [Background technology]

[0002] In thin films formed by the conventional atomic layer deposition (ALD) process, the ligands of the precursor compounds injected during the deposition process are not fully removed and remain in the growing thin film, which causes contamination by introducing impurities into the thin film.

[0003] That is, when thin films are formed in the horizontal direction due to miniaturization of semiconductor devices, impurities (C, Cl) in the thin films originating from ligands - , F - ) can disrupt the crystal arrangement and reduce the density of the thin film that is formed.

[0004] The low density can cause problems with electrical conductivity, and the miniaturization and stacking of semiconductor devices has led to an increase in the use of substrates that include deep vertical via holes or trenches.

[0005] When filling cylindrical hole patterns or trenches, or forming a thin film along vertical inner walls, it is difficult to achieve 100% step coverage, which is the uniform thickness of the thin film formed on the top of the pattern and the bottom of the trench.

[0006] Therefore, there is a need for a thin film formation method that enables the formation of thin films with complex structures, reduces the amount of residual impurities, and significantly improves step coverage and thin film thickness uniformity, as well as semiconductor substrates and other products manufactured thereby.

[0007]

[0008] [Prior art document]

[0009] [Patent documents]

[0010] (Patent Document 1) Korean Patent Publication No. 2019-0140104 Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been made to solve the problems of the prior art described above, and aims to provide a thin film formation method that effectively shields a substrate and improves film quality by using a reaction surface pretreatment agent in combination with a ligand replacement agent, thereby improving the reaction rate and appropriately reducing the thin film growth rate, and significantly improving step coverage and thin film thickness uniformity and reducing impurities, even when a thin film is formed on a substrate having a complex structure, and a semiconductor substrate manufactured thereby.

[0012] The present invention aims to improve step coverage by using a reaction surface pretreatment agent, and to improve film quality such as electrical properties, dielectric properties, and thin film density by using a ligand displacement agent.

[0013] The above and other objects of the present invention can be achieved by the present invention described below. [Means for solving the problem]

[0014] In order to achieve the above object, the present invention provides

[0015] The present invention provides a method for forming a thin film, comprising the steps of injecting a reaction surface pretreatment agent into a chamber to shield a surface of a loaded substrate, injecting a precursor compound into the chamber to adsorb it onto the shielded surface of the substrate, injecting a ligand replacement agent into the chamber to replace a ligand of the adsorbed precursor compound, and injecting a reaction gas into the chamber to form a thin film.

[0016] The reaction surface pretreatment agent may contain linear or cyclic, saturated or unsaturated hydrocarbons having two or more types of nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) and having 3 to 15 carbon atoms.

[0017] The reaction surface pretreatment agent may include a compound having a structure containing nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S) at both ends of a central carbon atom connected to oxygen by a double bond.

[0018] The reaction surface pretreatment agent may include a compound having a structure containing nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) at one end of a central carbon atom connected to oxygen by a double bond and carbon (C) at the other end.

[0019] The reaction surface pretreatment agent may be at least one selected from the compounds represented by the following Chemical Formula 1 to 4.

[0020] [Chemical formula 1]

[0021] [ka]

[0022] [Chemical formula 2]

[0023] [ka]

[0024] [Chemical formula 3]

[0025] [ka]

[0026] [Chemical formula 4]

[0027] [ka]

[0028] (In the above Chemical Formulas 1 to 4, R 1 and R 2 are each independently H or an alkyl group having 1 to 5 carbon atoms, R3, R4 and R5 are each independently H or -(Me)z-CH3, where Me is a saturated or unsaturated hydrocarbon having 1 to 3 carbon atoms and z is an integer of 0 to 4, and R' and R ” are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkene group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms;

[0029] A is oxygen (O), sulfur (S), phosphorus (P), nitrogen (N), -CH, or -CH2;

[0030] B is -OH, -OCH3, -OCH2CH3, -CH2CH3, -SH, -SCH3, or -SCH2CH3;

[0031] X is fluorine (F), chlorine (Cl), bromine (Br) or iodine (I);

[0032] The Y is carbon (C) or silicon (Si);

[0033] n is an integer from 1 to 4, and m is an integer from 0 to 3.

[0034] The reaction surface pretreatment agent may include one or more compounds selected from the compounds represented by the following Chemical Formulae 1-1 to 1-6, 2-1 to 2-4, 3-1 to 3-4, and 4-1 to 4-4.

[0035] [Chemical formula 1-1~1-6]

[0036] [ka]

[0037] [Chemical formula 2-1~2-4]

[0038] [ka]

[0039] [Chemical formula 3-1~3-4]

[0040] [ka]

[0041] [Chemical formula 4-1~4-4]

[0042] [ka]

[0043] The ligand displacement agent may be at least one selected from hydrogen iodide, hydrogen iodide water, methyl iodide, ethyl iodide, propyl iodide, butyl iodide, isopropyl iodide, and tertiary butyl iodide.

[0044] The ligand replacement agent is a single substance of 3N-15N hydrogen iodide, a gas mixture of 1-99% by weight of 3N-15N hydrogen iodide and the balance of an inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5-70% by weight of 3N-15N hydrogen iodide and the balance of water to make the total amount 100% by weight, where the inert gas can be nitrogen, helium or argon having a purity of 4N-9N.

[0045] The ligand displacement agent may have a refractive index of 1.40 or more, 1.42 to 1.50, 1.43 to 1.48, or 1.44 to 1.48.

[0046] The reaction surface pretreatment agent and the ligand replacement agent can provide a replacement region for an oxide film, a nitride film, a metal film, or a selective thin film thereof.

[0047] The thin film may be a laminate film of one or more elements 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.

[0048] The thin film may be formed on the entire substrate or on a portion of the substrate on which the oxide film, nitride film, metal film, or selective thin film thereof is formed.

[0049] The thin film is formed for the purpose of a diffusion barrier film, an etching stop film, an electrode film, a dielectric film, a gate insulating film, a block oxide film, or a charge trap, and can improve step coverage and various film qualities during the formation.

[0050]

[0051] The precursor compound used in the thin film formation method may be a compound represented by the following Chemical Formula 5.

[0052] [Chemical formula 5]

[0053] [ka]

[0054] (In the above Chemical Formula 5, M is at least one 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; L 1 , L 2 , L 3 and L 4 is -H, -X, -R, -OR, or -NR 2 and may be the same or different, where -X is F, Cl, Br or I, and -R is C1-C 10 Alkyl, C1-C 10 Alkenes, or C1-C 10 and wherein L is an alkane, which may be linear or cyclic. 1 , L 2 , L 3 and L 4 can be formed with n being 2 to 6 in L depending on the oxidation value of the central metal.)

[0055] As an example, when the central metal is divalent, L 1 and L 2 can be attached to the central metal as a ligand, and if the central metal is hexavalent, L 1 , L 2 , L 3 , L 4 , L 5 , L 6 can be attached to the central metal, and L 1 ~L 6 The ligands corresponding to may be the same or different from each other).

[0056] In the above Chemical Formula 5, L 1 , L 2 , L 3 and L 4 is -H or -R, which may be the same or different, and where -R is C1 to C 10 Alkyl, C1-C 10Alkenes, or C1-C 10 and wherein L is an alkane, which may be linear or cyclic. 1 , L 2 , L 3 and L 4 can be formed with n being 2 to 6 in L depending on the oxidation value of the central metal.

[0057] As an example, when the central metal is divalent, L 1 and L 2 can be attached to the central metal as a ligand, and if the central metal is hexavalent, L 1 , L 2 , L 3 , L 4 , L 5 , L 6 can be attached to the central metal, and L 1 ~L 6 The ligands corresponding to may be the same or different from each other).

[0058] In the above Chemical Formula 5, L 1 , L 2 , L 3 and L 4 is -H, -OR, or -NR 2 may be the same or different, where -R is H, C1-C 10 Alkyl, C1-C 10 Alkenes, C1-C 10 alkane, iPr, or TBu.

[0059] In the above Chemical Formula 5, L 1 , L 2 , L 3 and L 4 are -H or -X, which may be the same or different from each other, where -X can be F, Cl, Br or I.

[0060]

[0061] The present invention also relates to

[0062] The present invention provides a method for forming a thin film, comprising the steps of: injecting the reaction surface pretreatment agent into a chamber to shield a surface of a loaded substrate; primarily purging the interior of the chamber with a purge gas; injecting a precursor compound into the chamber to adsorb it onto the shielded surface of the substrate; secondly purging the interior of the chamber with a purge gas; injecting the ligand replacement agent into the chamber to replace the ligand of the adsorbed precursor compound; thirdly purging the interior of the chamber with a purge gas; and injecting a reaction gas into the chamber to form a thin film.

[0063] The precursor compound may be a precursor that is a molecule consisting of one or more species 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, and has a vapor pressure at 25°C of more than 0.01 mTorr and not more than 100 Torr.

[0064] 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.

[0065] After the reaction surface pretreatment agent, ligand replacement agent, or precursor compound is vaporized and injected, a step of plasma post-treatment may be included.

[0066] The amount of purge gas introduced into the chamber in each step may be 10 to 100,000 times the volume of the reaction surface pretreatment agent, precursor compound, or ligand replacement agent introduced.

[0067] The reaction gas is an oxidizing agent, a nitriding agent or a reducing agent, and the reaction gas, the reaction surface pretreatment agent, the ligand replacement agent and the precursor compound can be delivered into the chamber by a VFC method, a DLI method or an LDS method.

[0068] The thin film may be a tungsten film, a molybdenum film, a silicon nitride film, a silicon nitride film, a silicon oxide film, a titanium nitride film, a titanium oxide film, a tungsten nitride film, a molybdenum nitride film, a hafnium oxide film, a zirconium oxide film, a tungsten oxide film, or an aluminum oxide film.

[0069] The substrate loaded into the chamber is heated to 100 to 800° C., and the ratio of the reaction surface pretreatment agent to the precursor compound and the ligand replacement agent introduced into the chamber (mg / cycle) may be 1:1 to 1:20:0.5 to 1.0.

[0070] The present invention also provides a semiconductor substrate produced by the above-mentioned thin film formation method.

[0071] The thin film may be a multi-layer structure of two or three layers.

[0072]

[0073] The present invention also provides a semiconductor device including the semiconductor substrate described above.

[0074] The semiconductor substrate can be low resistive metal gate interconnects, high aspect ratio 3D metal-insulator-metal (MIM) capacitors, DRAM trench capacitors, 3D Gate-All-Around (GAA), or 3D NAND flash memory. Effect of the Invention

[0075] According to the present invention, by sequentially applying a reaction surface pretreatment agent and a ligand replacement agent together with a precursor compound, it is possible to simultaneously provide a gradation adsorption effect of the reaction surface pretreatment agent on the reaction surface and an improvement effect of the film quality by the ligand replacement agent. Even when a thin film is formed on a substrate having a complex structure, it is possible to significantly improve step coverage and film thickness uniformity of the thin film, and it is possible to provide a method for forming a thin film that significantly reduces impurities and improves film quality.

[0076] In addition, the process by-products during the formation of the thin film are more effectively reduced, corrosion and deterioration are prevented, and the film quality is modified to improve the crystallinity of the thin film, thereby improving the electrical characteristics of the thin film.

[0077] In addition, the use of a reaction surface pretreatment agent can improve step coverage, and the use of a ligand replacement agent can improve film qualities such as electrical properties, dielectric properties, and thin film density. Furthermore, it is possible to provide a thin film formation method using the same and a semiconductor substrate manufactured thereby. [Brief description of the drawings]

[0078] [Figure 1] FIG. 2 is a diagram illustrating a deposition process sequence according to the present invention, focusing on one cycle.

[0079] [Diagram 2] 1 is a graph comparing the deposition speed of a thin film in Example 1 according to the present invention and Comparative Examples 1 to 3 which deviate from the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0080]

[0081] The above-described thin film forming method and the semiconductor substrate produced thereby will now be described in detail.

[0082] In this description, the term "reaction surface pretreatment agent", unless otherwise specified, means not only reducing, preventing or blocking the adsorption of precursor compounds for forming a thin film onto a substrate, but also reducing, preventing or blocking the adsorption of process by-products onto a substrate, and refers to a substance that can provide a gradation adsorption effect on a reaction surface.

[0083] In this description, the term "ligand displacing agent", unless otherwise specified, refers to a substance that can displace the ligand of a precursor compound to provide a film quality improving effect.

[0084] In this description, unless otherwise specified, the term "modification" means that a substance other than the precursor and reactant actively interacts with the reaction surface to improve the film quality, such as reducing the resistivity of the deposited thin film, increasing the density, reducing impurities, and improving step coverage.

[0085] The present inventors have found that by combining a reaction surface pretreatment agent capable of blocking the adsorption of a precursor compound supplied to form a thin film on the surface of a substrate loaded inside a chamber with a ligand replacement agent capable of modifying the film quality of the thin film produced, the use of the reaction surface pretreatment agent can improve step coverage, and the use of the ligand replacement agent can improve film quality such as electrical properties, dielectric properties, and thin film density. Based on this finding, the present inventors have incorporated the findings into research on thin film modification compositions and have completed the present invention.

[0086]

[0087] The thin film may be provided as one or more precursors selected from the group consisting of, for example, 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, and may provide an oxide film, a nitride film, or a metal film. In this case, the effects to be achieved in the present invention may be sufficiently obtained.

[0088] Specific examples of the thin film include a silicon nitride film, a silicon oxide film, a titanium nitride film, a titanium oxide film, a tungsten nitride film, a molybdenum nitride film, a hafnium oxide film, a zirconium oxide film, a tungsten oxide film, and an aluminum oxide film.

[0089] The thin film may contain the above-mentioned film compositions alone or as selective areas, but is not limited thereto, and is meant to include SiH and SiOH.

[0090] The thin film can be used in semiconductor devices not only as a commonly used diffusion barrier film, but also as an etching stop film, an electrode film, a dielectric film, a gate insulating film, a block oxide film, or a charge trap.

[0091]

[0092] In the present invention, the precursor compound used to form a thin film is a molecule having 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, or Nd as a central metal atom (M) and one or more ligands consisting of C, N, O, H, or X (halogens), and in the case of a precursor having a vapor pressure of 1 mTorr to 100 Torr at 25° C., the effect of being pretreated with the reaction surface pretreatment agent and the effect of being substituted with the ligand replacement agent can be maximized.

[0093] As an example of the precursor compound, a compound represented by the following Chemical Formula 5 can be used.

[0094] [Chemical formula 5]

[0095] [ka]

[0096] (In the above Chemical Formula 5, M is at least one selected from 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; L 1 , L 2 , L 3 and L 4 is -H, -X, -R, -OR, or -NR 2 and may be the same or different, where -X is F, Cl, Br or I, and -R is C1-C 10 Alkyl, C1-C 10 Alkenes, or C1-C 10 which may be linear or cyclic, 1 , L 2 , L 3 and L 4 The n number of L may range from 2 to 6 depending on the oxidation value of the central metal.

[0097] As an example, when the central metal is divalent, L 1 and L 2 can be attached to the central metal as a ligand, and if the central metal is hexavalent, L 1 , L 2 , L 3 , L 4 , L 5 , L 6 can be attached to the central metal, and L 1 ~L 6 The ligands corresponding to may be the same or different from each other).

[0098] In the formula 5, M is hafnium (Hf), silicon (Si), zirconium (Zr), titanium (Ti), or aluminum (Al), and preferably hafnium (Hf), titanium (Ti), or silicon (Si). In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the effect of improving the thin film density, and the electrical properties, insulation properties, and dielectric properties of the thin film are further excellent.

[0099] Said L 1 , L 2 , L 3 and L 4 are -H or -R, which may be the same or different, and where -R is C1 to C 10 Alkyl, C1-C 10 Alkenes, or C1-C 10 and may have a linear or cyclic structure, in which case it has the appropriate degree of reactive energy to be displaced by the ligand displacers described below.

[0100] In addition, the above-mentioned L 1 , L 2 , L 3 and L 4 is -H, -OR, or -NR 2 may be the same or different, where -R is H, C1-C 10 Alkyl, C1-C 10 Alkenes, C1-C 10 alkane, iPr, or tBu, which have the appropriate degree of reaction energy to be displaced by the ligand displacer described below.

[0101] In addition, in the above-mentioned Chemical Formula 5, L 1 , L 2 , L 3 and L 4 is -H or -X, which may be the same or different, where -X may be F, Cl, Br or I, and has a suitable degree of reaction energy to be displaced by a ligand displacing agent as described below.

[0102] Specifically, examples of silicon precursor compounds include SiH4, SiHCl3, SiH2Cl2, SiCl4, Si2Cl6, Si3Cl8, and Si4Cl. 10, SiH2[NH(C4H9)]2, Si2(NHC2H5)4, Si3NH4(CH3)3, and one or more selected from SiH3[N(CH3)2], SiH2[N(CH3)2]2, SiH[N(CH3)2]3, and Si[N(CH3)2]4 can be used, in which case they have a suitable degree of reaction energy to be substituted by the ligand substitution agent described below.

[0103] Examples of hafnium precursor compounds that can be used include tris(dimethylamido)cyclopentadienylhafnium, CpHf(NMe2)3, and (methyl-3-cyclopentadienylpropylamino)bis(dimethylamino)hafnium, Cp(CH2)3NM3Hf(NMe2)2, which have a suitable degree of reaction energy to be substituted by the ligand substitution agent described below.

[0104] As the titanium precursor compound, for example, TiCl4, Ti(CpMe5)(OMe)3, etc. can be used, and in this case, it has a suitable degree of reaction energy to be substituted by the ligand substitution agent described later.

[0105] For example, the precursor compound can be used by mixing with a non-polar solvent. In this case, there is an advantage that the viscosity and vapor pressure of the precursor compound can be easily adjusted.

[0106]

[0107] The reaction surface pretreatment agent is characterized by containing linear or cyclic saturated or unsaturated hydrocarbon having 3 to 15 carbon atoms and having two or more types of nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S). In this case, when forming a thin film, a shielding region that does not remain in the thin film is formed to form a relatively sparse thin film, side reactions are suppressed, the thin film growth rate is controlled, and process by-products in the thin film are reduced to reduce corrosion and deterioration, the crystallinity of the thin film is improved, and a stoichiometric oxidation state is reached when a metal oxide film is formed. Even when a thin film is formed on a substrate having a complex structure, there are effects of significantly improving step coverage and uniformity of the thin film thickness.

[0108] As a specific example, the reaction surface pretreatment agent includes a compound having a structure containing nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) at both ends of a central carbon atom connected to oxygen by a double bond, thereby having a large effect of reducing process by-products and excellent step coverage, as well as an effect of improving thin film density and excellent electrical properties of the thin film.

[0109] Here, unless otherwise specified, the structure containing nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) at both ends of the central carbon atom connected to the oxygen by a double bond is [ka] Refers to...

[0110] As a specific example, the reaction surface pretreatment agent has a structure in which one end of a central carbon atom connected to oxygen by a double bond contains nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) and the other end contains carbon (C), thereby exhibiting a large effect of reducing process by-products, excellent step coverage, and further excellent effects of improving thin film density and electrical properties of the thin film.

[0111] Here, unless otherwise specified, the structure containing nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) at one end of the central carbon atom connected to the oxygen by a double bond and carbon (C) at the other end is [ka] Refers to...

[0112] The reaction surface pretreatment agent may be one or more selected from the compounds represented by the following formulas 1 to 4, and in this case, when forming a thin film, a shielding region that does not remain in the thin film is formed, a relatively sparse thin film is formed, side reactions are suppressed, the thin film growth rate is controlled, process by-products in the thin film are reduced, corrosion and deterioration are reduced, and the crystallinity of the thin film is improved. Even when a thin film is formed on a substrate having a complex structure, step coverage and thickness uniformity of the thin film can be significantly improved.

[0113] [Chemical formula 1]

[0114] [ka]

[0115] [Chemical formula 2]

[0116] [ka]

[0117] [Chemical formula 3]

[0118] [ka]

[0119] [Chemical formula 4]

[0120] [ka]

[0121] (In the above Chemical Formulas 1 to 4, R 1 and R 2 are each independently H or an alkyl group having 1 to 5 carbon atoms, R3, R4 and R5 are each independently H or -(Me)z-CH3, where Me is a saturated or unsaturated hydrocarbon having 1 to 3 carbon atoms and z is an integer of 0 to 4, and R' and R ” are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkene group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms;

[0122] A is oxygen (O), sulfur (S), phosphorus (P), nitrogen (N), -CH, or -CH2;

[0123] B is -OH, -OCH3, -OCH2CH3, -CH2CH3, -SH, -SCH3, or -SCH2CH3;

[0124] X is fluorine (F), chlorine (Cl), bromine (Br) or iodine (I);

[0125] The Y is carbon (C) or silicon (Si);

[0126] n is an integer from 1 to 4, and m is an integer from 0 to 3.

[0127] In the above Chemical Formula 1, R 1 and R 2 is an alkyl group having 1 to 5 carbon atoms, and preferably an alkyl group having 2 to 4 carbon atoms. In this case, there are advantages such as a large effect of reducing process by-products and excellent step coverage, as well as an effect of improving the thin film density and further excellent electrical properties, insulating properties, and dielectric properties of the thin film.

[0128] In the above Chemical Formula 1, n is an integer of 2 to 4, preferably an integer of 3 to 4. In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the thin film density is improved, and the electrical properties, insulating properties, and dielectric properties of the thin film are further excellent.

[0129] In the above formula 2, A is oxygen (O) or sulfur (S), and preferably oxygen (O). In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the effect of improving the thin film density, and the electrical properties, insulating properties, and dielectric properties of the thin film are further excellent.

[0130] The R' is an alkyl group having 1 to 3 carbon atoms, and preferably an alkyl group having 1 to 2 carbon atoms. In this case, there are advantages such as a large effect of reducing process by-products and excellent step coverage, as well as an effect of improving thin film density and further excellent electrical properties, insulating properties and dielectric properties of the thin film.

[0131] The above m is an integer of 1 to 2, and is preferably an integer of 1.

[0132] In Formula 3, B is -OH, -OCH3, -OCH2CH3, -CH2CH3, -SH, -SCH3, or -SCH2CH3. In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the effect of improving the thin film density, and the electrical properties of the thin film are further excellent.

[0133] The R″ is an alkyl group having 1 to 3 carbon atoms, and preferably an alkyl group having 1 to 2 carbon atoms. In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the effect of improving the thin film density, and the electrical properties of the thin film are further excellent.

[0134] In the formula 4, Y is carbon (C) or silicon (Si). In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the effect of improving the thin film density, and the electrical properties of the thin film are further excellent.

[0135] In the formula 4, X is chlorine (Cl), bromine (Br) or iodine (I), preferably bromine (Br) or iodine (I). In this case, there are advantages in that the effect of reducing process by-products is large, the step coverage is excellent, the effect of improving the thin film density and the electrical properties of the thin film are further excellent.

[0136] In the above Chemical Formula 4, R3, R4 and R5 are -(Me)z-CH3, where Me is a saturated or unsaturated hydrocarbon having 1 to 3 carbon atoms, and z is an integer of 0 to 4, preferably z is an integer of 0 to 2. In this case, there are advantages in that the effect of reducing process by-products is large and the step coverage is excellent, as well as the effect of improving the thin film density and the electrical properties, insulating properties and dielectric properties of the thin film are further excellent.

[0137]

[0138] When the reaction surface pretreatment agent is, for example, a compound represented by Chemical Formula 1, it may be a compound having a refractive index in the range of 1.4 to 1.42, or 1.43 to 1.5, specifically 1.41 to 1.417, or 1.43 to 1.47, preferably 1.413 to 1.417, or 1.450 to 1.452.

[0139] When the reaction surface pretreatment agent is, for example, a compound represented by Chemical Formula 2, it may be a compound having a refractive index of 1.39 or less, specifically 1.3 to 1.39, and preferably 1.35 to 1.385.

[0140] The reaction surface pretreatment agent may include at least one compound selected from the group consisting of compounds represented by the following formulas 1-1 to 1-6, 2-1 to 2-4, 3-1 to 3-4, and 4-1 to 4-4. In this case, the reaction surface pretreatment agent has a high effect of providing a thin film shielding region to control a thin film growth rate, a high effect of removing process by-products, and an excellent effect of improving step coverage and film quality.

[0141] [Chemical formula 1-1~1-6]

[0142] [ka]

[0143] [Chemical formula 2-1~2-4]

[0144] [ka]

[0145] [Chemical formula 3-1~3-4]

[0146] [ka]

[0147] [Chemical formula 4-1~4-4]

[0148] [ka]

[0149] The reaction surface pretreatment agent is characterized in that it does not remain on the thin film.

[0150] Here, unless otherwise specified, "not remaining" refers to the presence of less than 0.1 atomic % (atom %) of C element, less than 0.1 atomic % (atom %) of Si element, less than 0.1 atomic % (atom %) of N element, and less than 0.1 atomic % (atom %) of halogen elements in a component analysis by XPS. More preferably, in a measurement method by secondary-ion mass spectrometry (SIMS) in which measurements are made while digging into the substrate in the depth direction, or a measurement method by X-ray photoelectron spectroscopy (XPS), when considering the increase / decrease rates of C, N, Si, and halogen impurities before and after using an activator under the same deposition conditions, it is preferable that the increase / decrease rate of the signal sensitivity (intensity) of each element type does not exceed 5%.

[0151]

[0152] The ligand displacing agent of the present invention can provide sufficient adsorption area on the substrate by lowering the activation energy of the precursor compound adsorbed on the substrate and effectively displacing the ligand in the precursor compound. That is, it is preferable to use a compound that can displace the ligand of the precursor compound adsorbed on the substrate.

[0153] The ligand may be substituted, for example, on the entire substrate or a portion of the substrate on which a thin film is to be formed using the reaction surface pretreatment agent and precursor compound.

[0154] As an example, when the total area of ​​the entire substrate or a portion of the substrate on which the thin film is to be formed (total area of ​​the substrate) is taken as 100%, the region on which the thin film is to be formed (hereinafter referred to as the "shielded region") may occupy, for example, 10 to 95% of the area, specifically 15 to 90%, preferably 20 to 85%, more preferably 30 to 80%, even more preferably 40 to 75%, and still more preferably 40 to 70%, and the unshielded region may occupy the remaining area.

[0155] When the total area of ​​the entire substrate or a portion of the substrate (the entire area of ​​the substrate) is taken as 100%, the first shielded region may occupy 10 to 95% of the area, specifically 15 to 90%, preferably 20 to 85%, more preferably 30 to 80%, even more preferably 40 to 75%, and even more preferably 40 to 70% of the area; the second shielded region may occupy 10 to 95% of the remaining area, specifically 15 to 90%, preferably 20 to 85%, more preferably 30 to 80%, even more preferably 40 to 75%, and even more preferably 40 to 70%, and the unshielded region may occupy the remaining area.

[0156]

[0157] The ligand replacement agent is at least one selected from hydrogen iodide, hydrogen iodide water, methyl iodide, ethyl iodide, propyl iodide, butyl iodide, isopropyl iodide, and tertiary butyl iodide. In this case, not only can side reactions during thin film formation be suppressed, thin film growth rate be controlled, process by-products in the thin film be reduced, corrosion and deterioration be reduced, and the crystallinity of the thin film be improved, but also a stoichiometric oxidation state can be reached during the formation of a metal oxide film, and even when a thin film is formed on a substrate having a complex structure, step coverage and thin film thickness uniformity can be significantly improved.

[0158] As a specific example, the ligand replacement agent is a single substance of 3N to 15N hydrogen iodide, a gas mixture of 1 to 99% by weight of 3N to 15N hydrogen iodide and the remaining amount of inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 3N to 15N hydrogen iodide and the remaining amount of water to make the total amount 100% by weight. Here, when the inert gas is nitrogen, helium or argon having a purity of 4N to 9N, it has a large effect of reducing process by-products and excellent step coverage, as well as an effect of improving thin film density and excellent electrical properties of the thin film.

[0159] Preferably, the ligand replacement agent is a single substance of 5N-6N hydrogen iodide, a gas mixture of 1-99% by weight of 5N-6N hydrogen iodide and the remaining amount of inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5-70% by weight of 5N-6N hydrogen iodide and the remaining amount of water to make the total amount 100% by weight, where the inert gas can be nitrogen, helium or argon having a purity of 4N-9N. In this case, when forming a thin film, side reactions are suppressed, the thin film growth rate is controlled, process by-products in the thin film are reduced, corrosion and deterioration are reduced, and not only is it possible to improve film quality such as improving the crystallinity of the thin film by reducing side reactions and controlling the thin film growth rate, but also it is possible to significantly improve step coverage and thickness uniformity of the thin film even when the thin film is formed on a substrate having a complex structure.

[0160]

[0161] The ligand replacement agent is preferably a single substance of 5N-6N hydrogen iodide, a gas mixture of 1-99% by weight of 5N-6N hydrogen iodide and the remaining amount of inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5-70% by weight of 5N-6N hydrogen iodide and the remaining amount of water to make the total amount 100% by weight, where the inert gas can be nitrogen, helium or argon having a purity of 4N-9N.

[0162] When the ligand displacement agent is, for example, a hydrogen iodide compound, it may be a compound having a refractive index within the range of 1.4 to 1.42, or 1.43 to 1.5, specifically 1.41 to 1.417, or 1.43 to 1.47, preferably 1.413 to 1.417, or 1.450 to 1.452.

[0163] In such a case, the adsorption of the precursor compound to the substrate is appropriately shielded by reducing the activation energy required for the ligand substitution reaction of the activator having the above-mentioned structure on the substrate, thereby improving the reaction rate, significantly improving the step coverage and the film thickness uniformity of the thin film even when the thin film is formed on a substrate having a complex structure, and effectively protecting the surface of the substrate by preventing the adsorption of not only the thin film precursor but also the process by-products, and effectively removing the process by-products.

[0164]

[0165] The reaction surface pretreatment agent or ligand replacement agent may preferably 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 thin film or cause a side reaction with the precursor or reactant, so it is preferable to use a substance having a purity of 99% or more.

[0166] The reaction surface pretreatment agent and the ligand replacement agent are preferably used in an atomic layer deposition (ALD) process, and in this case, have the advantages of effectively protecting the substrate surface without interfering with the adsorption of the precursor compound, and effectively removing process by-products.

[0167] The reaction surface pretreatment agent and the ligand replacement agent preferably have a density of 0.8 to 3.0 g / cm 3 , 0.8~2.9g / cm 3 , 1.8~2.9g / cm 3 or 0.8~1.8g / cm 3 Within this range, a replacement region can be effectively formed, and there is an effect that the step coverage, the film thickness uniformity of the thin film, and the improvement of the film quality are excellent.

[0168]

[0169] The thin film may contain, for example, 100 ppm or less of halogen compounds. For reference, if an excessive amount of halogen remains, when a nitriding agent is used under the temperature condition of 200 to 300° C., which is the experimental condition described later, chlorides such as NH4Cl are generated and remain in the thin film, which is not preferable.

[0170] The thin film can be used as an etching stop film, an electrode film, a dielectric film, a gate insulating film, a block oxide film, or a charge trap, but is not limited to these.

[0171] In particular, since a relatively sparse thin film is formed and the growth rate of the formed thin film is significantly reduced, even when applied to a substrate having a complex structure, the uniformity of the thin film is ensured and the step coverage is significantly improved. In particular, the method can provide effects such as being able to deposit a thin film and improving the amount of O, Si, metal, metal oxide, and even carbon remaining as process by-products, which was previously difficult to reduce.

[0172]

[0173] A method for forming a thin film according to an embodiment of the present invention includes a step of injecting the above-mentioned reaction surface pretreatment agent into a chamber to block a part of a reaction site where a precursor compound adsorbed on a surface of a loaded substrate is adsorbed. In this case, the precursor adsorbed on the substrate is effectively replaced to improve the reaction rate and appropriately reduce the thin film growth rate, thereby improving step coverage and significantly improving the uniformity of the thin film even when a thin film is formed on a substrate having a complex structure.

[0174] In the step of shielding the surface of the substrate with the reactive surface pretreatment agent, the feeding time (seconds (sec)) of the reactive surface pretreatment agent to the surface of the substrate is preferably 0.01 to 10 seconds, more preferably 0.02 to 8 seconds, even more preferably 0.04 to 6 seconds, and even more preferably 0.05 to 4 seconds per cycle. Within this range, there are advantages such as a low thin film growth rate, excellent step coverage, and excellent cost-effectiveness.

[0175] In this description, the feeding time of the reaction surface pretreatment agent is based on a flow rate of 0.1 to 50 mg / cycle in a chamber volume of 15 to 20 L, and more specifically, based on a flow rate of 0.8 to 20 mg / cycle in a chamber volume of 18 L.

[0176]

[0177] A method for forming a thin film according to another embodiment of the present invention includes a step of injecting the ligand replacing agent into a chamber to replace the ligand of a precursor compound adsorbed on a surface of a loaded substrate. In this case, the ligand of the precursor adsorbed on the substrate is effectively replaced to improve the reaction rate and appropriately reduce the thin film growth rate, thereby significantly improving the film quality such as electrical properties, dielectric properties, thin film density, etc., even when a thin film is formed on a substrate having a complex structure.

[0178] In this description, the feeding time of the ligand displacement agent is based on a flow rate of 0.1 to 8,000 mg / cycle with a chamber volume of 15 to 20 L, and more specifically, based on a flow rate of 10 to 5,000 mg / cycle with a chamber volume of 18 L.

[0179]

[0180] As a preferred embodiment, the thin film formation method may include the steps of: i) vaporizing the reaction surface pretreatment agent to shield the surface of the substrate loaded into the chamber; ii) performing a primary purge of the interior of the chamber with a purge gas; iii) vaporizing a precursor compound and adsorbing it to an area outside the shielded area; iv) performing a secondary purge of the interior of the chamber with a purge gas; v) vaporizing the ligand replacement agent to activate the adsorbed area; vi) performing a tertiary purge of the interior of the chamber with a purge gas; vii) supplying a reaction gas into the interior of the chamber; and viii) performing a quaternary purge of the interior of the chamber with a purge gas. In this case, steps i) to viii) are regarded as a unit cycle, and the cycle can be repeated until a thin film having a desired thickness is obtained (see FIG. 1 below). In this manner, when the reaction surface pretreatment agent is added prior to the precursor compound in one cycle to be adsorbed on the substrate, and the ligand replacement agent is added after the precursor compound to improve the film quality, even if deposition is performed at a high temperature, the thin film growth rate can be appropriately reduced, the process by-products generated are effectively removed, the resistivity of the thin film is reduced, step coverage is significantly improved, and the uniformity of the thin film is improved, and the film quality such as electrical properties, dielectric properties, and thin film density is improved.

[0181] As a preferred example of the thin film formation method of the present invention, in one cycle, the reaction surface pretreatment agent of the present invention can be added prior to a precursor compound to be adsorbed onto a substrate, and the ligand replacement agent can be added after the precursor compound to replace the ligand of the precursor. In this case, even if the thin film is deposited at a high temperature, the thin film growth rate can be appropriately reduced, so that process by-products can be significantly reduced, step coverage can be significantly improved, and the crystallinity of the thin film can be increased to reduce the resistivity of the thin film. Even if the thin film is applied to a semiconductor device having a large aspect ratio, the uniformity of the thin film thickness can be significantly improved, ensuring the reliability of the semiconductor device, and improving film quality such as electrical properties, dielectric properties, and thin film density.

[0182] In the thin film formation method, for example, when the reaction surface pretreatment agent is deposited before or after deposition of a precursor compound, a unit cycle can be repeated 1 to 99,999 times as necessary, and preferably the unit cycle can be repeated 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 effect to be achieved in the present invention can be sufficiently obtained while obtaining the desired thin film thickness.

[0183] The chamber may be, by way of example, an ALD chamber, a CVD chamber, a PEALD chamber, or a PECVD chamber.

[0184] After the reaction surface pretreatment agent, ligand replacement agent, or precursor compound is vaporized and injected, a step of plasma post-treatment may be included, in which case the growth rate of the thin film can be improved and process by-products can be reduced.

[0185]

[0186] When the reaction surface pretreatment agent and the ligand replacement agent are sequentially injected onto the substrate and the precursor compound is adsorbed thereon, the amount of purge gas introduced into the chamber in the step of purging the unadsorbed reaction surface pretreatment agent and the unadsorbed ligand replacement agent is not particularly limited as long as it is an amount sufficient to remove the unadsorbed reaction surface pretreatment agent and the unadsorbed ligand replacement agent, but may be 10 to 100,000 times, preferably 50 to 50,000 times, more preferably 100 to 10,000 times, and within this range, the unadsorbed reaction surface pretreatment agent and the unadsorbed ligand replacement agent are sufficiently removed to uniformly form a thin film and prevent deterioration of the film quality. Here, the amounts of the purge gas, the reaction surface pretreatment agent, and the ligand replacement agent introduced are based on one cycle, and the amounts of the reaction surface pretreatment agent and the ligand replacement agent refer to the volumes of the vaporized reaction surface pretreatment agent vapor and the ligand replacement agent vapor.

[0187] As a specific example, in the step of injecting the reaction surface pretreatment agent and the ligand replacement agent at a flow rate of 100 mL / cycle (injection time 1 second), and purging the unadsorbed reaction surface pretreatment agent and the unadsorbed ligand replacement agent, respectively, when a purge gas is injected at a flow rate of 3000 mL / min (injection time 10 seconds), the injection amount of the purge gas is 300 times the injection amount of the reaction surface pretreatment agent and the ligand replacement agent.

[0188]

[0189] In addition, the amount of purge gas introduced into the chamber in the step of purging the unadsorbed precursor compound is not particularly limited as long as it is an amount sufficient to remove the unadsorbed precursor compound, but as an example, it may be 10 to 10,000 times, preferably 50 to 50,000 times, more preferably 100 to 10,000 times based on the volume of the precursor compound introduced into the chamber, and within this range, the unadsorbed precursor compound can be sufficiently removed to form a thin film uniformly and prevent deterioration of the film quality. Here, the amounts of the purge gas and the precursor compound introduced are each based on one cycle, and the volume of the precursor compound means the volume of the vaporized precursor compound vapor.

[0190]

[0191] In the purge step performed immediately after the reaction gas supply step, the amount of purge gas introduced into the chamber may be, for example, 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times the volume of the reaction gas introduced into the chamber, and the desired effect can be sufficiently obtained within this range. Here, the amounts of the purge gas and reaction gas introduced are each based on one cycle.

[0192]

[0193] The reaction surface pretreatment agent, the ligand replacement agent and the precursor compound can be preferably delivered into the chamber by the VFC method, the DLI method or the LDS method, and more preferably delivered into the chamber by the LDS method.

[0194] The substrate loaded in the chamber may be heated to, for example, 50 to 400° C., specifically, 50 to 400° C., and the reaction surface pretreatment agent, ligand replacement agent, or precursor compound may be injected onto the substrate in an unheated or heated state, and the heating conditions may be adjusted during the deposition process after being injected in an unheated state depending on deposition efficiency. For example, the reaction surface pretreatment agent, ligand replacement agent, or precursor compound may be injected onto the substrate at 50 to 400° C. for 1 to 20 seconds.

[0195]

[0196] The ratio of the amounts (mg / cycle) of the reaction surface pretreatment agent and the precursor compound fed into the chamber may be preferably 1:1.5 to 1:20, more preferably 1:2 to 1:15, even more preferably 1:2 to 1:12, and still more preferably 1:2.5 to 1:10. Within this range, the effect of improving step coverage and the effect of reducing process by-products are large.

[0197]

[0198] The thin film formation method can be carried out at a deposition temperature in the range of, for example, 50 to 800°C, preferably at a deposition temperature in the range of 100 to 700°C, more preferably at a deposition temperature in the range of 200 to 650°C, even more preferably at a deposition temperature in the range of 220 to 400°C, and even more preferably at a deposition temperature in the range of 220 to 300°C. Within this range, there is an effect of growing a thin film with excellent film quality while realizing the ALD process characteristics.

[0199] The thin film formation method can be carried out, for example, at a deposition pressure in the range of 0.01 to 20 Torr, preferably at a deposition pressure in the range of 0.1 to 20 Torr, more preferably at a deposition pressure in the range of 0.1 to 10 Torr, and most preferably at a deposition pressure in the range of 0.3 to 7 Torr. Within this range, there is an effect that a thin film with a uniform thickness can be obtained.

[0200] In this description, deposition temperature and deposition pressure may be measured as the temperature and pressure established within a deposition chamber, or may be measured as the temperature and pressure applied to a substrate within the deposition chamber.

[0201] The thin film formation method may preferably include a step of raising the temperature in the chamber to a deposition temperature before introducing the reaction surface pretreatment agent into the chamber, and / or a step of injecting an inert gas into the chamber to purge the chamber before introducing the reaction surface pretreatment agent into the chamber.

[0202]

[0203] In the thin film formation method, the strength (c / s) of residual halogen in the thin film, based on a thin film thickness of 100 Å, measured based on SIMS, can be preferably 100,000 or less, more preferably 70,000 or less, even more preferably 50,000 or less, and even more preferably 10,000 or less. In a preferred embodiment, it can be 5,000 or less, more preferably 1,000 to 4,000, and even more preferably 1,000 to 3,800. Within this range, the effect of preventing corrosion and deterioration is outstanding.

[0204] In this description, the purge rate is preferably 1,000 to 50,000 sccm (Standard Cubic Centimeters per Minute), more preferably 2,000 to 30,000 sccm, and even more preferably 2,500 to 15,000 sccm. Within this range, the thin film growth rate per cycle is appropriately controlled, and deposition is performed as or approximately as an atomic mono-layer, which is advantageous in terms of film quality.

[0205]

[0206] The present invention may also include, as a thin film manufacturing apparatus capable of realizing the thin film manufacturing method, a thin film manufacturing apparatus including an ALD chamber, a first vaporizer for vaporizing a reaction surface pretreatment agent, a first transport means for transporting the vaporized reaction surface pretreatment agent into the ALD chamber, a second vaporizer for vaporizing a precursor compound, a second transport means for transporting the vaporized precursor compound into the ALD chamber, a third vaporizer for vaporizing a ligand replacement agent, and a third transport means for transporting the vaporized ligand replacement agent into the ALD chamber. Here, the vaporizer and the transport means are not particularly limited as long as they are vaporizers and transport means commonly used in the technical field to which the present invention pertains.

[0207] The first vaporizer for vaporizing the reaction surface pretreatment agent may be divided into at least two types, such as a vaporizer for vaporizing the reaction surface pretreatment agent and a vaporizer for vaporizing the ligand replacement agent, as necessary.

[0208] As a specific example, the method of forming the thin film will be described. First, a substrate on which a thin film is to be formed is placed in a deposition chamber capable of depositing atomic layers.

[0209] The substrate may be a semiconductor substrate such as a silicon substrate or a silicon oxide substrate.

[0210] The substrate may further have a conductive or insulating layer formed thereon.

[0211] In order to deposit a thin film on a substrate placed in the deposition chamber, the above-mentioned reaction surface pretreatment agent and a precursor compound or a mixture thereof with a non-polar solvent are prepared.

[0212] Then, the prepared reaction surface pretreatment agent is injected into a vaporizer, converted into a vapor phase, and transferred to a deposition chamber to be adsorbed on a substrate, and then purged to remove unadsorbed reaction surface pretreatment agent.

[0213] Next, the prepared precursor compound or a mixture of the precursor compound and a non-polar solvent (hereinafter referred to as "thin film forming composition") is injected into a vaporizer, converted into a vapor phase, and transferred to a deposition chamber to be adsorbed onto a substrate. The reaction surface is shielded by a pre-injected reaction surface pre-treatment agent, and unadsorbed precursor compound or a mixture of the precursor compound and a non-polar solvent is purged.

[0214] The non-polar solvent may be at least one selected from the group consisting of alkanes and cycloalkanes. In this case, the non-polar solvent has the advantage of improving step coverage even when the deposition temperature is increased during the formation of a thin film, while containing an organic solvent having low reactivity and solubility and easy moisture management.

[0215] In a more preferred example, the non-polar solvent is a C1 to C 10 Alkanes of C3 to C 10 and preferably C3 to C 10 In this case, the reactivity and solubility are low, and water management is easy.

[0216] In this description, C1, C3, etc. refer to the carbon numbers.

[0217] The cycloalkane is preferably a C 10 Among the monocycloalkanes, cyclopentane is liquid at room temperature and has the highest vapor pressure, and therefore is suitable for the vapor deposition process, but is not limited thereto.

[0218] The non-polar solvent has, for example, a solubility in water (25° C.) of 200 mg / L or less, preferably 50 to 400 mg / L, and more preferably 135 to 175 mg / L. Within this range, the non-polar solvent has the advantages of low reactivity with the precursor compound and easy moisture control.

[0219] In this description, the solubility is not particularly limited to the measurement methods and standards commonly used in the technical field to which the present invention pertains, and as an example, a saturated solution can be measured by high performance liquid chromatography (HPLC).

[0220] The non-polar solvent may preferably comprise 5 to 95% by weight, more preferably 10 to 90% by weight, even more preferably 40 to 90% by weight, and most preferably 70 to 90% by weight, based on the total weight of the precursor compound and the non-polar solvent.

[0221] If the content of the non-polar solvent exceeds the upper limit, impurities are induced, and the resistance and the number of impurities in the thin film are increased. If the content of the organic solvent is less than the lower limit, the effect of improving step coverage and the effect of reducing impurities such as chlorine (Cl) ions by adding the solvent are not obtained.

[0222]

[0223] Then, the prepared ligand replacement agent is injected into a vaporizer, converted into a vapor phase, and delivered to a deposition chamber for adsorption, and the unadsorbed ligand replacement agent is purged.

[0224] In this description, examples of a method for delivering a reaction surface pretreatment agent, a ligand replacement agent, a precursor compound (a composition for forming a thin film), and the like to a deposition chamber include a method for delivering a volatilized gas using a mass flow controller (MFC) (Vapor Flow Control: VFC), or a method for delivering a liquid using a liquid mass flow controller (LMFC) (Liquid Delivery System: LDS), and preferably an LDS method is used.

[0225] In this case, the carrier gas or dilution gas for transporting the reaction surface pretreatment agent, the ligand replacement agent, the precursor compound, etc. onto the substrate may be one or a mixture of two or more gases selected from the group consisting of argon (Ar), nitrogen (N2), and helium (He), but is not limited thereto.

[0226] In this description, the purge gas may be, for example, an inert gas, and preferably the above-mentioned carrier gas or dilution gas.

[0227]

[0228] Then, a reaction gas is supplied. The reaction gas is not particularly limited as long as it is a reaction gas commonly used in the technical field to which the present invention pertains, and may preferably include a nitriding agent. The nitriding agent reacts with a precursor compound adsorbed on the substrate to form a nitride film.

[0229] Preferably, the nitriding agent can be nitrogen gas (N2), hydrazine gas (N2H4), or a mixture of nitrogen gas and hydrogen gas.

[0230] The remaining unreacted reactant gas is then purged with an inert gas, which removes not only the excess reactant gas but also any by-products that are produced.

[0231] As described above, the thin film formation method, for example, includes a unit cycle including the steps of supplying a reaction surface pretreatment agent onto a substrate, purging unadsorbed reaction surface pretreatment agent, adsorbing a precursor compound / thin film formation composition onto a substrate, purging unadsorbed precursor compound, adsorbing a ligand replacement agent onto a substrate, purging unadsorbed ligand replacement agent, supplying a reaction gas, and purging residual reaction gas, and the unit cycle can be repeated to form a thin film of a desired thickness.

[0232] The unit cycle can be repeated, for example, 1 to 99,999 times, preferably 10 to 1,000 times, more preferably 50 to 5,000 times, and further preferably 100 to 2,000 times. Within this range, the desired thin film properties can be effectively exhibited.

[0233]

[0234] The present invention also provides a semiconductor substrate, characterized in that the semiconductor substrate is manufactured by the thin film formation method described above. In such a case, the thin film has excellent step coverage and thickness uniformity, and has excellent density and electrical properties.

[0235]

[0236] The thin film thus produced preferably has a thickness of 20 nm or less, a resistivity of 50 to 400 μΩ·cm based on a thin film thickness of 10 nm, a halogen content of 10,000 ppm or less, and a step coverage rate of 90% or more. Within these ranges, the thin film has excellent performance as a diffusion barrier film and has the effect of reducing corrosion of metal wiring materials, but is not limited thereto.

[0237] The thin film may have a thickness of, for example, 0.1 to 20 nm, preferably 1 to 20 nm, more preferably 3 to 25 nm, and even more preferably 5 to 20 nm. Within this range, the thin film has excellent thin film properties.

[0238] The thin film may have a resistivity of, for example, 0.1 to 400 μΩ·cm, preferably 15 to 300 μΩ·cm, more preferably 20 to 290 μΩ·cm, and even more preferably 25 to 280 μΩ·cm, based on a thin film thickness of 10 nm. Within this range, the thin film has the effect of having excellent thin film characteristics.

[0239] The thin film may have a halogen content of preferably 10,000 ppm or less, or 1 to 9,000 ppm, more preferably 5 to 8,500 ppm, and even more preferably 100 to 1,000 ppm. Within this range, the thin film has excellent thin film properties while reducing the thin film growth rate. Here, the halogen remaining in the thin film may be, for example, Cl2, Cl, or Cl. - The lower the amount of residual halogen in the thin film, the better the film quality, which is preferable.

[0240] As an example, the thin film has a step coverage of 90% or more, preferably 92% or more, and more preferably 95% or more. Within this range, even if the thin film has a complex structure, it can be easily deposited on a substrate, and has the advantage of being applicable to next-generation semiconductor devices.

[0241] The thin film thus produced preferably has a thickness of 20 nm or less, a carbon, nitrogen, and halogen content of 10,000 ppm or less based on a thickness of 10 nm, and a step coverage rate of 90% or more. Within these ranges, the thin film has the effect of exhibiting excellent performance as a dielectric film or a blocking film, but is not limited thereto.

[0242]

[0243] The thin film may have a multilayer structure of two or three layers as required, for example. The multilayer film having a two-layer structure may have a structure of a lower layer film-middle layer film as a specific example, and the multilayer film having a three-layer structure may have a structure of a lower layer film-middle layer film-upper layer film as a specific example.

[0244] The underlayer film may, for example, comprise one or more selected from the group consisting of Si, SiO2, MgO, Al2O3, CaO, ZrSiO4, ZrO2, HfSiO4, Y2O3, HfO2, LaLuO2, Si3N4, SrO, La2O3, Ta2O5, BaO, and TiO2.

[0245] The intermediate layer is, for example, Ti x Ny , preferably TN.

[0246] The upper layer film may contain, for example, one or more selected from the group consisting of W and Mo.

[0247]

[0248] Below, preferred embodiments and drawings are presented to aid in understanding the present invention. However, the following embodiments and drawings are merely illustrative of the present invention, and it will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the present invention and the technical spirit thereof. It goes without saying that such changes and modifications are also included within the scope of the appended claims.

[0249]

[0250] [Example]

[0251] Example 1, Comparative Examples 1 to 3

[0252] An ALD deposition process was carried out according to FIG. 1 below using the components shown in Table 1 below.

[0253] FIG. 1 is a schematic diagram illustrating a deposition process sequence according to the present invention, focusing on one cycle.

[0254] Specifically, a compound represented by the following chemical formula 3-1 was prepared as the reaction surface pretreatment agent, and a 5N compound represented by the following chemical formula 7 was prepared as the ligand replacement agent. TiCl4 was also prepared as the precursor.

[0255] [Chemical formula 3-1]

[0256] [ka]

[0257] [Chemical formula 7]

[0258] [ka]

[0259] As shown in Figure 1 below, the prepared reaction surface pretreatment agent was placed in a canister and supplied to a vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. The reaction surface pretreatment agent vaporized in the vapor phase in the vaporizer was introduced into a deposition chamber loaded with a substrate for 2 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the reaction chamber was controlled to 2.5 Torr.

[0260] The prepared precursor compound was then placed in a separate canister and fed to a separate vaporizer heated to 150°C at a flow rate of 0.1 g / min using a liquid mass flow controller (LMFC) at room temperature. TiCl4 vaporized in the vapor phase in the vaporizer was fed into the deposition chamber for 2 seconds, and argon gas was then fed at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure inside the reaction chamber was controlled to 2.5 Torr.

[0261] The prepared ligand replacement agent was then placed in a canister and fed to the chamber at room temperature using a mass flow controller (MFC) at a flow rate of 100 mL / min. The ligand replacement agent vaporized in the vapor phase in the vaporizer was fed into the deposition chamber with the substrate loaded for 2 seconds, and then argon gas was supplied at 5000 sccm for 10 seconds to perform argon purging. At this time, the pressure in the reaction chamber was controlled to 2.5 Torr.

[0262] Next, 1000 sccm of ammonia as a reactive gas was introduced into the reaction chamber for 2 seconds, and then argon purging was carried out for 10 seconds. At this time, the substrate on which the metal thin film was to be formed was heated to 100°C.

[0263] This process was repeated 200 to 400 times to form a self-limiting atomic layer thin film with a thickness of 10 nm.

[0264] For each of the obtained thin films of Example 1 and Comparative Examples 1 to 3, the deposition rate (D / R) and secondary ion mass spectrometry (SIMS) C impurities were measured by the following method, and the results are shown in Table 1 and FIG.

[0265] Specifically, the film thickness of the thin film was measured using an ellipsometer, a device that can measure optical properties such as the film thickness and refractive index of a thin film using the polarization characteristics of light, and divided by the number of cycles to calculate the film thickness deposited per cycle.

[0266] The deposition rates (D / R) shown in Table 1 below are values ​​measured using an ellipsometer on a thin film having a thickness of 3 to 30 nm under conditions of room temperature and pressure, and are expressed in units of Å / cycle.

[0267] * SIMS (Secondary-ion mass spectrometry) C impurity: The C impurity value in the SIMS graph was confirmed by taking into consideration the C impurity content (counts) when the thin film was axially excavated by ion sputtering and the sputtering time was 50 seconds, which is the least contaminated part of the surface layer of the substrate.

[0268] [Table 1]

[0269] As shown in Table 1 and Figure 2 below, Example 1, which used the reaction surface pretreatment agent and ligand replacement agent according to the present invention, was confirmed to have a significantly improved deposition rate and excellent impurity reduction characteristics compared to Comparative Example 1, which did not use either. However, Example 1, which used the reaction surface pretreatment agent and ligand replacement agent according to the present invention, did not show an improvement in deposition rate compared to Comparative Example 2, which did not use the ligand replacement agent, but it was confirmed that Example 1, which used the reaction surface pretreatment agent and ligand replacement agent according to the present invention, not only showed a significantly improved deposition rate but also had excellent impurity reduction characteristics compared to Comparative Example 3, which did not use the reaction surface pretreatment agent.

[0270] Therefore, it has been confirmed that by sequentially applying the reaction surface pretreatment agent and the ligand replacement agent according to the present invention to a precursor compound, it is possible to significantly improve the film thickness uniformity of the thin film, significantly reduce impurities, and improve film quality, even when the thin film is formed on a substrate having a complex structure, thereby providing a thin film required for semiconductor devices that require step coverage and improved film quality.

Claims

1. 1. A method for forming a thin film, comprising: injecting a reaction surface pretreatment agent into a chamber to shield a surface of a loaded substrate; injecting a precursor compound into the chamber to adsorb the precursor compound onto the shielded surface of the substrate; injecting a ligand replacement agent into the chamber to replace a ligand of the adsorbed precursor compound; and injecting a reaction gas into the chamber to form a thin film.

2. 2. The thin film formation method according to claim 1, wherein the reaction surface pretreatment agent contains a linear or cyclic, saturated or unsaturated hydrocarbon having two or more types of nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) and having 3 to 15 carbon atoms.

3. 2. The method of claim 1, wherein the reaction surface pretreatment agent includes a compound having a structure containing nitrogen (N), oxygen (O), phosphorus (P), or sulfur (S) at both ends of a central carbon atom connected to oxygen by a double bond.

4. 2. The method of claim 1, wherein the reaction surface pretreatment agent comprises a compound having a structure containing nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) at one end of a central carbon atom connected to oxygen by a double bond and carbon (C) at the other end.

5. The method of forming a thin film according to claim 1, wherein the reaction surface pretreatment agent is one or more compounds selected from the compounds represented by the following chemical formulas 1 to 4: [Chemical formula 1] 【Chemistry 1】 [Chemical formula 2] 【Chemistry 2】 [Chemical formula 3] 【Chemistry 3】 [Chemical formula 4] 【Chemistry 4】 (In the above Chemical Formulas 1 to 4, R １ and R ２ are each independently H or an alkyl group having 1 to 5 carbon atoms, R ３ , R ４ and R ５ are each independently H or -(Me)z-CH ３ where Me is a saturated or unsaturated hydrocarbon having 1 to 3 carbon atoms, z is an integer of 0 to 4, and R′ and R ” are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkene group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms; The A is oxygen (O), sulfur (S), phosphorus (P), nitrogen (N), -CH, or -CH ２ and The B is —OH, —OCH ３ , -OCH ２ CH ３ , -CH ２ CH ３ , -SH, -SCH ３ , or -SCH ２ CH ３ and X is fluorine (F), chlorine (Cl), bromine (Br) or iodine (I); The Y is carbon (C) or silicon (Si); n is an integer from 1 to 4, and m is an integer from 0 to 3.

6. The reaction surface pretreatment agent includes at least one compound selected from the group consisting of compounds represented by the following formulas 1-1 to 1-6, 2-1 to 2-4, 3-1 to 3-4, and 4-1 to 4-4. [Chemical formulas 1-1 to 1-6] 【Chemistry 5】 [Chemical formulas 2-1 to 2-4] 【Chemistry 6】 [Chemical formulas 3-1 to 3-4] 【Chemistry 7】 [Chemical formulas 4-1 to 4-4] 【Chemistry 8】

7. 2. The method of claim 1, wherein the ligand replacement agent is at least one selected from the group consisting of hydrogen iodide, hydrogen iodide water, methyl iodide, ethyl iodide, propyl iodide, butyl iodide, isopropyl iodide, and tertiary butyl iodide.

8. The method of claim 1, wherein the ligand replacement agent is a single substance of 3N to 15N hydrogen iodide, a gas mixture of 1 to 99% by weight of 3N to 15N hydrogen iodide and the balance of an inert gas to make the total amount 100% by weight, or an aqueous solution mixture of 0.5 to 70% by weight of 3N to 15N hydrogen iodide and the balance of water to make the total amount 100% by weight, wherein the inert gas is nitrogen, helium or argon having a purity of 4N to 9N.

9. 2. The thin film forming method according to claim 1, wherein the thin film is a laminated film of one or more elements selected from the group consisting of Al, 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.

10. 2. The method of claim 1, wherein the thin film is formed on the entire substrate or a portion of the substrate on which the oxide film, nitride film, metal film, or selective thin film thereof is to be formed.

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

12. 2. The method of claim 1, wherein the reaction surface pretreatment agent, precursor compound, or ligand replacement agent is delivered into the chamber by a vapor flow control (VFC) method, a direct liquid introduction (DLI) method, or a liquid delivery system (LDS) method, and the thin film is a silicon nitride film, a silicon oxide film, a titanium nitride film, a titanium oxide film, a tungsten nitride film, a molybdenum nitride film, a hafnium oxide film, a zirconium oxide film, a tungsten oxide film, or an aluminum oxide film.

13. A semiconductor substrate manufactured by the thin film forming method according to claim 1.

14. The semiconductor substrate according to claim 13, wherein the thin film has a multi-layer structure of two or three layers.

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

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