Activator, semiconductor substrate manufactured using same, and semiconductor device

Abstract

The present invention relates to an activator, a semiconductor substrate manufactured using the activator, and a semiconductor device, and a method for manufacturing a titanium-containing deposited film according to the present invention has the effect of easily manufacturing a high-purity deposited film through a simple process by using a titanium-based precursor compound and a specific reaction gas.

Description

Technical Field

[0001] The present invention relates to an activator, a semiconductor substrate and a semiconductor device manufactured using the same, and specifically provides an activator, a semiconductor substrate and a semiconductor device manufactured using the same, wherein a compound with a predetermined structure is used as a second ligand, which is replaced with a first ligand of a precursor compound to improve the reactivity with subsequently injected reactants, thereby improving the deposition reaction rate, greatly improving the density and resistivity of the deposited film, and greatly reducing impurities. Background Art

[0002] The ideal atomic layer deposition (ALD) process is based on a self-limiting reaction, and the ligands of the precursor adsorbed on the substrate prevent the deposition of the subsequently injected precursor. However, in the actual process, it may include partial thermal decomposition, that is, the ligands leave the central metal due to the influence of the thermal history of the precursor. This process has a chemical vapor deposition (CVD) property, and the greater the property, the lower the step coverage, the density and thickness uniformity of the deposited film. In addition, if the type of the departing ligand is F, Cl, etc., which is easy to adsorb on the surface or easily form fluoride or chloride, there is a problem that it may remain as an impurity on the deposited film (refer to J.Phys.Chem.B.13491-8, "Surface chemistry in the atomic layerdeposition of TiN films from TiCl4and ammonia" (2006)).

[0003] The density and thickness uniformity of the above-mentioned deposited film are factors that affect the electrical and chemical properties. For example, the conductivity can be reduced, and the deposited film may be contaminated or the crystal arrangement of the deposited film may be disturbed due to the absorption of by-products (HCl, etc.) derived from the leaving groups of the above-mentioned halogen ligands, thereby leading to the problem of further reducing the density.

[0004] Therefore, it is important to reduce the thermal history of the precursor so that the process can be implemented in the atomic layer deposition window (ALD window). But in general, the higher the temperature at which the deposition is performed, the better the film quality can be obtained. For example, when depositing titanium nitride thin films, thin films deposited at higher temperatures exhibit lower resistivity. In order to obtain a thin film with low resistivity even if the deposition temperature is lowered, based on a self-limiting reaction, the first ligand of the precursor adsorbed on the substrate is replaced with a more reactive second ligand, which reacts with the reactant to form a deposited film with a complex structure, and it is necessary to develop a second ligand and a deposited film manufacturing method using the same, a semiconductor substrate and a semiconductor device manufactured thereby, etc., wherein the second ligand not only improves the thickness uniformity and deposition reaction rate of the deposited film, but also reduces the amount of impurities remaining, which can greatly increase the density, thereby improving electrical properties such as resistivity. Summary of the invention

[0005] Problem that the invention aims to solve

[0006] In order to solve the problems of the above-mentioned prior art, the purpose of the present invention is to provide an activator, a semiconductor substrate and a semiconductor device manufactured using the same, which provide a compound with a predetermined structure as a second ligand to replace the first ligand of the precursor compound, thereby greatly improving the deposition reaction rate, the thickness uniformity and density of the deposited film, and further improving the electrical properties.

[0007] The above-mentioned object and other multiple objects of the present invention can all be achieved by the present invention described below.

[0008] Means used to solve problems

[0009] In order to achieve the above object, the present invention provides an activator, which comprises an alkyl-free halide for replacing a ligand of a precursor compound bonded to a Group 4 central metal.

[0010] In addition, the present invention provides an activator, the activator comprising an alkyl free halide, wherein the alkyl free halide is used to fill a ligand leaving site of a precursor compound bonded to a Group 4 central metal.

[0011] When the precursor compound contains a halogen, the halogen is referred to as a first halogen, and the halogen constituting the halide not containing an alkyl group may be a second halogen different from the first halogen.

[0012] The first halogen may be at least one selected from fluorine, chlorine, iodine and bromine.

[0013] The second halogen may be one or more selected from iodine and bromine.

[0014] The alkyl-free halide may form an intermediate for providing a deposited film having a substance derived from the reactant bonded to the Group 4 metal.

[0015] The above-mentioned substances derived from the reactants may be H2O, H2O2, O2, O3, O radical, D2, H2, H radical, NH3, NO2, N2O, N2, N radical, H2S or S.

[0016] The above-mentioned intermediate may refer to a state in which a first ligand of a precursor compound is replaced by providing a compound of a predetermined structure as a second ligand.

[0017] The above-mentioned Group 4 central metal may be titanium.

[0018] The halide not containing an alkyl group may be an iodine donor not containing an alkyl group, hydrogen iodide gas, hydrogen bromide gas, iodine ions or iodine radicals.

[0019] The above deposition can be carried out by atomic layer deposition (ALD), plasma enhanced atomic layer deposition (PEALD), chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), metal organic chemical vapor deposition (MOCVD) or low pressure chemical vapor deposition (LPCVD).

[0020] In addition, the present invention provides a semiconductor substrate, wherein the precursor adsorption state before the ligand is replaced on the substrate is set to -MX n (n = 1 to 3, X = F, Cl), the precursor adsorption state after replacing the ligand is -MY m (m=1~3, Y=Br, I).

[0021] The change in the precursor adsorption state before and after replacing the above-mentioned ligand can occur due to the reaction between the precursor compound and the alkyl free halide on the above-mentioned substrate, wherein the above-mentioned precursor compound is formed by bonding a first halogen to a Group 4 central metal, and the above-mentioned alkyl free halide contains a second halogen for filling the ligand leaving site of the above-mentioned precursor compound.

[0022] The semiconductor substrate may include a deposited film formed by replacing a first halogen atom (F or Cl) on the central metal (M) of the chemical formula 1 with a second halogen atom (Br or I).

[0023] The deposited film may include a structure represented by Chemical Formula 2 below.

[0024] [Chemical formula 2]

[0025] M a H d

[0026] (In the above chemical formula 2, M is a Group 4 metal, H is one or more of O, N, and S, a is an integer of 1, and d is 1 to 2.2).

[0027] The composition of the deposited film can be confirmed by XPS analysis.

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

[0029] The deposition thickness of the above-mentioned deposited film measured by ellipsometer can be the following.

[0030] The resistivity of the deposited film may be 300 μΩ·cm or less.

[0031] The density of the deposited film can be 4.5 g / cm 3 above.

[0032] The iodine atom count of the deposited film measured by secondary ion mass spectrometry (SIMS) is 50 counts / second or more.

[0033] The above-mentioned deposited film may be an oxide film, a nitride film, a metal film or a sulfide film, and may be used as an anti-diffusion film, an etching stopper film, an electrode film, a dielectric film, a gate insulating film, a blocking oxide film or a charge trap.

[0034] In addition, the present invention provides a semiconductor device including the above-mentioned semiconductor substrate.

[0035] Effects of the Invention

[0036] According to the present invention, by replacing the leaving group of the precursor adsorbed on the substrate with the second halogen, the deposition reaction rate is improved and the thickness uniformity and density of the deposited film are appropriately increased, thereby having an activation effect to improve the productivity of the deposited film.

[0037] In addition, when forming a deposited film, while improving the density, process byproducts are more effectively reduced to prevent corrosion or degradation and improve the crystallinity of the deposited film, thereby having the effect of improving the electrical characteristics of the deposited film.

[0038] In addition, the thickness uniformity of the deposited film can be improved, thereby having the effect of providing a deposited film manufacturing method using the same, and a semiconductor substrate and a semiconductor device manufactured thereby. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1This is a graph comparing the deposition thickness and resistivity measured for 8 deposited films of Example 1 using an activator according to the present invention and 10 deposited films of Comparative Example 1 not using an activator.

[0040] Figure 2 This is a graph comparing the contents of process byproducts and impurities (Cl, O, Si, H, NH, metals, and metal oxides) measured by SIMS in Comparative Example 1 in which no activator was used.

[0041] Figure 3 This is a graph comparing the contents of process byproducts and impurities (Cl, O, Si, H, NH, metals, and metal oxides) measured by SIMS in Example 1 using an activator according to the present invention. DETAILED DESCRIPTION

[0042] Hereinafter, the activator of the present invention, and the semiconductor substrate and semiconductor device produced using the same will be described in detail.

[0043] The inventors of the present invention have confirmed that by providing a predetermined compound that can replace the ligand that leaves the precursor compound used to form a deposited film on the surface of the substrate loaded in the chamber as an activator, the deposition reaction rate can be improved and the thickness uniformity of the deposited film can be ensured, and the density and resistivity of the deposited film can be greatly improved, and the Cl, O, Si, H, NH, metals, metal oxides, etc. that remain as process byproducts can be reduced. Based on this, the inventors have devoted themselves to the study of activators and completed the present invention.

[0044] Hereinafter, the activator, the semiconductor substrate including the deposited film produced using the activator, and the semiconductor device will be specifically examined.

[0045] Activator

[0046] In the present invention, the activator is a deposition additive compound used to better form a deposited film on the surface of the substrate loaded in the chamber, and may be a predetermined compound capable of replacing the ligand to be removed.

[0047] As an example, the precursor compound may be a compound in which a halogen is bonded to a Group 4 central metal, so that when the precursor compound is injected into a substrate to form a deposited film, a considerable number of ligand leaving sites are formed where the halogen is left.

[0048] When the activator used in the present invention is an alkyl free halide, it can appropriately play a role of filling the above-mentioned ligand leaving site.

[0049] Unless otherwise specifically defined, the above term "alkyl free" excludes not only alkyl groups but also alkenyl groups or alkynyl groups.

[0050] When the halogen constituting the above-mentioned precursor compound is referred to as a first halogen, the halogen constituting the above-mentioned halide not containing an alkyl group may be a second halogen different from the above-mentioned first halogen.

[0051] The first halogen may be at least one selected from fluorine, chlorine, iodine and bromine.

[0052] The second halogen may be one or more selected from iodine and bromine.

[0053] Preferably, the above-mentioned activator can be a compound with a purity of 99.9% or more, a compound with a purity of 99.95% or more, or a compound with a purity of 99.99% or more. For reference, when a compound with a purity of less than 99% is used, impurities may remain in the deposited film or cause side reactions with precursors or reactants. Therefore, it is preferred to use substances with a purity of 99% or more as much as possible.

[0054] Preferably, the density of the activator is 1.0 to 4.0 g / cm 3 or 2.0~3.4g / cm 3 The vapor pressure can be 1 atmosphere at 180-240K. Within this range, it has excellent effects on improving step coverage, thickness uniformity of deposited films, resistivity and film quality.

[0055] The halide not containing an alkyl group may form an intermediate for providing a deposited film having a structure in which a substance derived from a reactant is bonded to the Group 4 metal.

[0056] Among them, the substance derived from the reactant can be H2O, H2O2, O2, O3, O radical, D2, H2, H radical, NH3, NO2, N2O, N2, N radical, H2S or S.

[0057] The above-mentioned alkyl-free halide is selected from one or more of an alkyl-free iodine donor, hydrogen iodide gas, hydrogen bromide gas, iodide ions or iodine free radicals. In this case, side reactions are suppressed and the growth rate of the deposited film is adjusted to reduce process byproducts in the deposited film, thereby reducing corrosion or degradation, and improving the crystallinity of the deposited film. When a metal oxide film is formed, it reaches a stoichiometric oxidation state. Even if a deposited film is formed on a substrate with a complex structure, the step coverage and the thickness uniformity of the deposited film can be greatly improved.

[0058] As a specific example, the above-mentioned activator is pure 3N~15N hydrogen iodide, or a gas mixture of 1~99 weight % of 3N~15N hydrogen iodide and an inert gas with the remainder making the total amount reach 100 weight %, or an aqueous solution mixture of 0.5~70 weight % of 3N~15N hydrogen iodide and water with the remainder making the total amount reach 100 weight %, among which, when the inert gas is nitrogen, helium or argon with a purity of 4N~9N, the effect of reducing process by-products is significant, the step coverage is excellent, and the effect of improving the density of the deposited film and the electrical properties of the deposited film can be better.

[0059] Preferably, the activator is a pure 3N-7N hydrogen iodide, or a gas mixture of 1-99 wt% of 5N-6N hydrogen iodide and an inert gas with a total amount of 100 wt% or an aqueous solution mixture of 0.5-70 wt% of 5N-6N hydrogen iodide and water with a total amount of 100 wt%, wherein the inert gas may be nitrogen, helium or argon with a purity of 4N-9N. In this case, when a deposited film is formed, a substitution region that does not remain in the deposited film is formed, and while a relatively sparse deposited film is formed, side reactions are suppressed and the growth rate of the deposited film is adjusted to reduce process byproducts in the deposited film, thereby reducing corrosion or degradation and improving the crystallinity of the deposited film. Even when a deposited film is formed on a substrate with a complex structure, the step coverage and the thickness uniformity of the deposited film can be greatly improved.

[0060] The present invention may include a step of performing plasma post-treatment after gasifying and injecting the above activator or precursor compound. In this case, the growth rate of the deposited film can be improved while reducing process byproducts.

[0061] The above deposition can be carried out by atomic layer deposition (ALD), plasma enhanced atomic layer deposition (PEALD), chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), metal organic chemical vapor deposition (MOCVD) or low pressure chemical vapor deposition (LPCVD).

[0062] Precursor compounds

[0063] In the present invention, the precursor compound used to form the deposited film is a molecule having a Group 4 metal as the central metal atom (M) and having one or more ligands composed of C, N, O, H, and X (halogen). The precursor having a vapor pressure of 1 mTorr to 100 Torr at 25°C can maximize the effect of filling the leaving site using the activator described later.

[0064] As an example, the precursor compound may be a compound represented by the following Chemical Formula 1.

[0065] [Chemical formula 1]

[0066]

[0067] (In the above chemical formula 1, M is a Group 4 metal, L1, L2, L3 and L4 are -H, -X, -R, -OR or -NR2, which may be the same as or different from each other, and may contain at least one -X, wherein -X is F, Cl or Br, and -R is a C1-C10 alkyl, a C1-C10 alkenyl or a C1-C10 alkynyl, which may be linear or cyclic.)

[0068] In the chemical formula 1, M is titanium (Ti). In this case, the effect of reducing process by-products is significant, the step coverage is excellent, and the deposited film density is improved, and the electrical properties and insulation properties of the deposited film are more excellent.

[0069] In the above Chemical Formula 1, L1, L2, L3 and L4 may be -H or -X, may be the same as or different from each other, and may include at least one -X, wherein -X may be F, Cl or Br.

[0070] In addition, for example, the titanium precursor compound may have a structure represented by the following Chemical Formula 1-1 or a structure represented by the following Chemical Formula 1-2.

[0071] [Chemical formula 1-1]

[0072]

[0073] The above-mentioned L1 can be H, F, Cl, Br, Me, Et, iPr, OMe, OEt, NMe2, NEt2 or NMeEt.

[0074] The above-mentioned L2 can be H, F, Cl, Br, Me, Et, iPr, OMe, OEt, NMe2, NEt2 or NMeEt.

[0075] The above-mentioned L3 can be H, F, Cl, Br, Me, Et, iPr, OMe, OEt, NMe2, NEt2 or NMeEt.

[0076] The above-mentioned L4 can be H, F, Cl, Br, Me, Et, iPr, OMe, OEt, NMe2, NEt2 or NMeEt.

[0077] The above L1 to L4 may be the same as or different from each other.

[0078] Unless otherwise specified, in the present invention, Me represents a methyl group and Et represents an ethyl group.

[0079] As an example, the structure represented by the above chemical formula 1-1 can be TiCl4, TiBr4, Ti(OMe)4, or Ti(NMe2)4.

[0080] [Chemical formula 1-2]

[0081]

[0082] The above L', L" and L'" may be independently OMe, OEt, NMe2, NEt2 or NMeEt.

[0083] The above R may be Me or Et.

[0084] n can be an integer from 0 to 5.

[0085] As an example, the compound represented by the above chemical formula 1-2 may be CpMeTi(OMe)3, CpMe2Ti(OMe)3, CpMe3Ti(OMe)3, CpMe4Ti(OMe)3, CpMe5Ti(OMe)3, CpMeTi(OEt)3, CpMe2Ti(OEt)3, CpMe3Ti(OEt)3, CpMe4Ti(OEt)3, CpMe5Ti(OEt)3, CpMeTi(NMe2)3, CpMe2Ti(NMe2)3, CpMe 3Ti(NMe2)3, CpMe4Ti(NMe2)3, CpMe5Ti(NMe2)3, CpMeTi(NEt2)3, CpMe2Ti(NEt2)3, CpMe3Ti(NEt2)3, CpMe4Ti(NEt2 )3, CpMe5Ti(NEt2)3, CpMeTi(NMeEt)3, CpMe2Ti(NMeEt)3, CpMe3Ti(NMeEt)3, CpMe4Ti(NMeEt)3 or CpMe5Ti(NMeEt)3.

[0086] As an example, in the present invention, the precursor compound may be mixed with a non-polar solvent and introduced into the chamber. In this case, the viscosity or vapor pressure of the precursor compound may be easily adjusted.

[0087] Preferably, the non-polar solvent may be one or more selected from alkanes and cycloalkanes. In this case, it may contain an organic solvent with low reactivity and solubility and easy moisture management, and may also have the advantage of improving step coverage when forming a deposited film even when the deposition temperature is increased.

[0088] As a more preferred example, the non-polar solvent may include C1-C10 alkane or C3-C10 cycloalkane, preferably C3-C10 cycloalkane. In this case, it has the advantages of low reactivity and solubility and easy water management.

[0089] In the present invention, C1, C3, etc. represent the number of carbon atoms.

[0090] Preferably, the cycloalkane may be a C3-C10 monocycloalkane. Among the monocycloalkane, cyclopentane is liquid at room temperature and has the highest vapor pressure, and is therefore preferred in the vapor deposition process, but is not limited thereto.

[0091] As an example, the solubility of the non-polar solvent in water (25° C.) is less than 200 mg / L, 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 to precursor compounds and easy water management.

[0092] In the present invention, there is no particular limitation on the solubility as long as it is based on a measurement method commonly used in the technical field to which the present invention belongs. As an example, a saturated solution can be measured by HPLC.

[0093] Based on the total weight of the precursor compound and the non-polar solvent, the content of the non-polar solvent may preferably be 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.

[0094] If, when the content of the above-mentioned non-polar solvent is greater than the above-mentioned upper limit value, impurities will be induced, thereby increasing the resistance and the impurity value in the deposited film. When the content of the above-mentioned organic solvent is less than the above-mentioned lower limit value, the improvement effect of step coverage and the reduction effect of impurities such as chloride (Cl) ions caused by adding the solvent are not obvious.

[0095] Deposition film

[0096] The present invention comprises a deposited film obtained by using the above activator.

[0097] The deposited film may be a multi-layer structure of two or more layers.

[0098] As an example, the deposited film may include a structure in which a substance derived from a reactant and a second halogen are bonded to a Group 4 metal.

[0099] The deposition thickness of the above deposited film measured by SIMS can be Below or

[0100] The resistivity of the deposited film may be 300 μΩ·cm or less, or 150 to 300 μΩ·cm. Within the above range, the conductivity can be improved.

[0101] The deposition rate of the above deposited film can be above, or

[0102] The density of the deposited film can be 4.8 g / cm 3 Above, or 4.8~5.3g / cm 3 .

[0103] The deposition rate increase rate of the above-mentioned deposited film represented by the following mathematical formula 1 can be greater than 10%. As a specific example, it can be greater than 12.5%, and preferably greater than 15%. In this case, while the deposited film is formed by the activator having the above-mentioned structure, the growth rate of the formed deposited film is greatly reduced, so that even if applied to a substrate with a complex structure, the uniformity of the deposited film can be ensured, thereby greatly improving the step coverage. In particular, deposition can be performed in a thin thickness, and the effect of improving the amount of O, Si, metals, metal oxides remaining as process by-products and residual carbon that is difficult to reduce in the prior art can be provided.

[0104] [Mathematical formula 1]

[0105] Deposition rate (DR) increase rate = [(DR f ) / (DR i )]×100

[0106] (In the above mathematical formula, DR (Deposition rate, / cycle) is the deposition rate of the deposited film. In the deposition of the deposited film formed by the precursor and the reactant, DR i (initial deposition rate) is the deposition rate of the deposited film formed without the addition of an activator. f The final deposition rate is the deposition rate of the deposited film formed by adding the activator during the above process. The deposition rate (DR) is the value of the deposited film with a thickness of 1 to 30 nm measured by an ellipsometer under normal temperature and pressure conditions. The unit is )

[0107] In the above mathematical formula 1, the deposition film growth rate per cycle when using an activator and when not using an activator refers to the deposition film deposition thickness of each cycle. That is, the deposition rate, as an example, refers to the average deposition rate calculated by measuring the final thickness of a deposited film with a thickness of 1 to 30 nm under normal temperature and pressure conditions using an ellipsometer and dividing it by the total number of cycles.

[0108] In the above mathematical formula 1, "when no activator is used" refers to a situation where only a precursor compound is adsorbed on a substrate to produce a deposited film in a deposited film deposition process. As a specific example, it refers to a situation where a deposited film is formed by omitting the step of adsorbing an activator and the step of purging the non-adsorbed activator in the above-mentioned deposited film formation method.

[0109] The deposited film may be a metal film, an oxidant, a nitride film, a sulfide film or a chalcogenide. In this case, the desired effect of the present invention can be fully achieved.

[0110] The deposited film may include the above-mentioned film components alone or in a selective area, but is not limited thereto, and means that it may also include SiH and SiOH.

[0111] The above-mentioned deposited film can be used not only as a commonly used anti-diffusion film, but also as an etching stopper film, an electrode film, a dielectric film, a gate insulating film, a blocking oxide film or a charge trap in a semiconductor device.

[0112] As an example, the content of the halogen compound in the deposited film measured using SIMS may be 10,500 counts / second or less.

[0113] Method for manufacturing deposited film

[0114] The deposited film can be produced by various methods, and can be produced by the following method as one example.

[0115] As a first step, a precursor compound including a Group 4 metal and a first halogen may be injected onto a substrate loaded into a chamber.

[0116] As an example, the first halogen may be one or more selected from fluorine, chlorine, iodine, and bromine, and preferably includes chlorine having excellent reactivity.

[0117] As an example, in the present invention, the method for transferring the precursor compound to the deposition chamber can adopt a method of transferring volatile gas (Vapor Flow Control; VFC) using a gas phase flow control (Mass Flow Controller; MFC) method, a liquid phase flow control (Liquid Mass Flow Controller; LMFC) method, and a method of transferring liquid (Liquid Delivery System; LDS).

[0118] At this time, as a carrier gas or dilution gas for transferring the precursor compound to the substrate, one or a mixed gas of two or more selected from argon (Ar), nitrogen (N2), and helium (He) can be used, but it is not limited thereto.

[0119] As an example, in the present invention, the purge gas may be an inert gas, preferably, the above-mentioned carrier gas or diluent gas.

[0120] The above-mentioned chamber can be an atomic layer deposition (ALD) chamber, a plasma assisted atomic layer deposition (PEALD) chamber, a chemical vapor deposition (CVD) chamber, a plasma enhanced chemical vapor deposition (PECVD) chamber, an organic metal chemical vapor deposition (MOCVD) chamber or a low pressure chemical vapor deposition (LPCVD) chamber.

[0121] The substrate loaded in the chamber may include a semiconductor substrate such as a silicon substrate or silicon oxide.

[0122] The substrate may further have a conductive layer or an insulating layer formed on an upper portion thereof.

[0123] The substrate may be maintained at 50 to 500°C, or 80 to 500°C.

[0124] As an example, the substrate may be heated to 50-500°C, specifically 80-500°C, 100-800°C or 200-500°C, and the activator or precursor compound may be injected into the substrate in an unheated state or a heated state. After the injection in an unheated state according to the deposition efficiency, the heating conditions may be adjusted during the next deposition process. As an example, the injection may be performed for 1-20 seconds onto a substrate heated to 300-600°C.

[0125] As an example, the ratio of the amount of the activator used in the second step described later to the amount of the precursor compound input into the chamber (mg / cycle) is 1:1 to 1:20, preferably 1:1 to 1:15, and more preferably 1:1 to 1:10. Within this range, the effect of improving step coverage and reducing process by-products is significant.

[0126] The first step may include one or more steps of purging with an inert gas. The inert gas may be a carrier gas or a diluent gas.

[0127] In the step of purging the non-adsorbed precursor compound, the amount of the purge gas introduced into the chamber is not particularly limited as long as it is sufficient to remove the non-adsorbed precursor compound. For example, the amount of the purge gas introduced into the chamber may be 10 to 100,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times, based on the volume of the precursor compound introduced into the chamber. Within this range, the non-adsorbed precursor compound is sufficiently removed, thereby forming a deposited film uniformly and preventing the degradation of the film quality. The amounts of the purge gas and precursor compound introduced are based on one cycle, respectively, and the volume of the precursor compound refers to the volume of the vaporized precursor compound vapor.

[0128] In the present invention, the purge is preferably 1,000 to 50,000 sccm (Standard Cubic Centimeter per Minute), more preferably 2,000 to 30,000 sccm, and even more preferably 2,500 to 15,000 sccm. Within this range, the growth rate of the deposited film per cycle is properly controlled, and deposition is performed in an atomic mono-layer or a manner close thereto, which is advantageous in terms of film quality.

[0129] As a second step, a halide containing no alkyl group and containing a second halogen different from the first halogen is injected into the substrate to replace the leaving site of the first halogen with the second halogen. In this case, the leaving group of the precursor adsorbed on the substrate is effectively replaced to improve the reaction rate and appropriately reduce the growth rate of the deposited film, thereby greatly improving the step coverage, resistivity and thickness uniformity of the deposited film even when the deposited film is formed on a substrate with a complex structure.

[0130] As an example, the second halogen may be one or more selected from iodine and bromine, and iodine is preferably used.

[0131] The feeding time (Feeding Time) of the activator to the above-mentioned substrate surface in each cycle is preferably 0.001 to 10 seconds, more preferably 0.02 to 3 seconds, more preferably 0.04 to 2 seconds, and further preferably 0.05 to 1 second. Within this range, the deposited film growth rate is high and the step coverage and economy are excellent.

[0132] In the present invention, the activator feeding time is based on a flow rate of 1 to 500 sccm when the chamber volume is 15 to 20 L, and more specifically, based on a flow rate of 10 to 200 sccm when the chamber volume is 18 L.

[0133] As an example, in the present invention, the activator may be transferred to the deposition chamber by transferring a volatile gas (Vapor Flow Control; VFC) using a Mass Flow Controller (MFC) method.

[0134] The second step may include one or more steps of purging with an inert gas. As an example, in the present invention, the purge gas may be the carrier gas or the diluent gas.

[0135] In the present invention, the purge is preferably 1,000 to 50,000 sccm (Standard Cubic Centimeter per Minute), more preferably 2,000 to 30,000 sccm, and even more preferably 2,500 to 15,000 sccm. Within this range, the growth rate of the deposited film in each cycle is properly controlled, and deposition is performed in an atomic mono-layer or in a manner close thereto, which is advantageous in terms of film quality.

[0136] In the step of purging the non-adsorbed activator, the amount of the purge gas introduced into the chamber is not particularly limited as long as it is sufficient to remove the non-adsorbed activator. For example, it can be 10 to 100,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times. Within this range, the non-adsorbed activator can be fully removed, so that the deposited film can be uniformly formed and the film quality can be prevented from being deteriorated. The amounts of the purge gas and the activator introduced are based on one cycle, respectively, and the volume of the activator refers to the volume of the vaporized activator vapor.

[0137] As a specific example, when the activator is injected at a flow rate of 100 sccm and an injection time of 0.5 sec (per cycle), and in the step of purging the unadsorbed activator, the purge gas is injected at a flow rate of 3000 sccm and an injection time of 5 sec (per cycle), the injection amount of the purge gas is 300 times the injection amount of the activator.

[0138] Thereafter, as a third step, a reactant may be injected into the substrate to form a deposited film derived from a Group 4 metal.

[0139] As an example, the above-mentioned reactants can be a gas including H2O, H2O2, O2, O3, O radical, D2, H2, H radical, NH3, NO2, N2O, N2, N radical, H2S or S.

[0140] The deposited film may include a structure in which a substance derived from a reactant and a second halogen are bonded to a Group 4 metal.

[0141] As an example, the above-mentioned deposited film forming method can be implemented at a deposition temperature in the range of 50 to 800°C, preferably, in the range of 100 to 700°C, more preferably, in the range of 200 to 650°C, and even more preferably, in the range of 220 to 500°C. Within this range, it has the effect of growing a deposited film with excellent film quality while achieving process characteristics.

[0142] As an example, the above-mentioned deposition film forming method can be implemented 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, the effect of obtaining a deposited film with uniform thickness can be achieved.

[0143] In the present invention, the deposition temperature and the deposition pressure may be measured by the temperature and pressure formed in the deposition chamber or by the temperature and pressure applied to the substrate in the deposition chamber.

[0144] Preferably, the second step may further include: a step of increasing the temperature in the chamber to the deposition temperature before adding the activator into the chamber; and / or a step of injecting an inactive gas for purging before adding the activator into the chamber.

[0145] The third step may include a step of purging with an inert gas.

[0146] In the purge step performed immediately after the reaction gas supply step, as an example, the amount of the purge gas introduced into the chamber may be 10 to 100,000 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. Within this range, the desired effect can be fully obtained. The amounts of the purge gas and the reaction gas introduced are based on one cycle, respectively.

[0147] In the present invention, the purge is preferably 1,000 to 50,000 sccm (Standard Cubic Centimeter per Minute), more preferably 2,000 to 30,000 sccm, and even more preferably 2,500 to 15,000 sccm. Within this range, the growth rate of the deposited film per cycle is properly controlled, and deposition is performed in an atomic mono-layer or in a manner close thereto, which is advantageous in terms of film quality.

[0148] In the above-mentioned deposited film forming method, as needed, the number of repetitions of the implemented unit cycle can be 1 to 99,999 times, 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 required thickness of the deposited film can be obtained and the effect to be achieved by the present invention can be fully achieved.

[0149] As a specific example, in the above-mentioned method for producing a deposited film, in order to deposit a deposited film on the substrate placed in the above-mentioned chamber, the above-mentioned activator and precursor compound or a mixture thereof with a non-polar solvent are prepared separately.

[0150] Thereafter, after the prepared precursor compound or a mixture thereof with a non-polar solvent is injected into the vaporizer, it is changed into a vapor phase so as to be transported to the deposition chamber and adsorbed on the substrate, the ligand of the above-mentioned precursor compound is replaced by the previously injected activator, and the non-adsorbed precursor compound is purged.

[0151] Next, after the prepared activator is injected into the vaporizer, it is changed into a vapor phase so as to be transported to the deposition chamber and adsorbed on the substrate, and purging is performed to remove the non-adsorbed activator.

[0152] In the present invention, as an example, the method of transferring the activator and precursor compounds to the deposition chamber can adopt a method of transferring volatile gas (VaporFlow Control; VFC) using a gas phase flow control (Mass Flow Controller; MFC) method or a method of transferring liquid (Liquid Delivery System; LDS) using a liquid phase flow control (Liquid Mass Flow Controller; LMFC) method.

[0153] At this time, as a carrier gas or dilution gas for transferring the activator and precursor compounds to the substrate, one or a mixed gas selected from argon (Ar), nitrogen (N2), and helium (He) can be used, but it is not limited to this.

[0154] As an example, in the present invention, the purge gas may be an inert gas, and preferably the above-mentioned carrier gas or diluent gas.

[0155] Next, a reactant is supplied. The reactant is not particularly limited as long as it is a reaction gas commonly used in the technical field to which the present invention belongs, and preferably, it may include a nitriding agent. The nitriding agent reacts with the precursor compound adsorbed on the substrate to form a nitride film.

[0156] Preferably, the nitriding agent may be nitrogen (N2), hydrazine (N2H4) or a mixture of nitrogen and hydrogen.

[0157] Next, the unreacted residual reaction gas is purged with an inert gas, thereby removing not only the excess reaction gas but also the generated by-products.

[0158] As described above, as an example, the above-mentioned deposited film forming method can take the steps of adsorbing the precursor compound on the substrate; the step of purging the unadsorbed precursor compound; the step of supplying the activator to the substrate; the step of purging the unadsorbed activator; the step of supplying the reaction gas; and the step of purging the residual reaction gas as a unit cycle, and repeat the above unit cycles to form a deposited film of a desired thickness.

[0159] As an example, the above-mentioned unit cycle may be repeated 1 to 99,999 times, preferably 10 to 1,000 times, more preferably 50 to 5,000 times, and even more preferably 100 to 2,000 times. Within this range, the desired deposited film effect can be fully exerted.

[0160] When the injection time and purge time of the precursor compound in the first step are set to a and b respectively, the injection time and purge time of the non-alkyl-containing halide in the second step are set to c and d respectively, and the injection time and purge time of the reactant in the third step are set to e and f respectively, 0.1≤a≤10, 2a≤b≤4a, 0.1<c≤10, 2c≤d≤8c, 2<e≤10, 2e≤b≤8e can be satisfied at the same time.

[0161] When the injection and purge of the precursor compound and the alkyl-free halide, and the injection and purge of the reactant are set as one cycle, the following four conditions can be satisfied at the same time: 1) The deposition thickness of the deposited film measured by the ellipsometer is 2) the resistivity of the deposited film is below 300 μΩ·cm; 3) the deposition rate is Above; 4) the density of the deposited film is 4.5g / cm 3 above.

[0162] The thickness of the deposited film measured by ellipsometer can be Below, or More preferably

[0163] The resistivity of the deposited film may be 300 μΩ·cm or less, or 10 to 300 μΩ·cm, and more preferably 30 to 200 μΩ·cm.

[0164] The density of the deposited film can be 4.5 g / cm 3 Above, or 4.5~5.5g / cm 3 .

[0165] The iodine atom count of the above-described deposited film measured by SIMS may be 50 counts / second or more.

[0166] When the injection and purge of the precursor compound and the alkyl-free halide, and the injection and purge of the reactant are set as one cycle, the following four conditions can be satisfied at the same time: 1) The deposition thickness of the deposited film measured by the ellipsometer is 2) The resistivity of the deposited film is 150-300 μΩ·cm; 3) The deposition rate is 4) The density of the deposited film is 4.8-5.5 g / cm 3 above.

[0167] As an example, the above-mentioned method for manufacturing a deposited film can be implemented by using a deposited film manufacturing device, which includes: an ALD chamber; a first vaporizer for vaporizing an activator; a first transfer unit for transferring the vaporized activator into the ALD chamber; a second vaporizer for vaporizing a deposited film precursor; and a second transfer unit for transferring the vaporized deposited film precursor into the ALD chamber. The vaporizer and the transfer unit are not particularly limited, as long as they are commonly used vaporizers and transfer units in the technical field to which the present invention belongs.

[0168] Semiconductor substrate

[0169] The present invention also provides a semiconductor substrate, which is manufactured by the deposited film forming method of the present invention or includes the deposited film. In this case, the step coverage and thickness uniformity of the deposited film are greatly improved, and the density and electrical properties of the deposited film are excellent.

[0170] As a specific example, the semiconductor substrate of the present invention can be provided as follows: the precursor adsorption state before the ligand is replaced on the substrate is set to -MX n (n = 1 to 3, X = F, Cl), the precursor adsorption state after replacing the ligand is called -MY m (m=1~3, Y=Br, I).

[0171] The change in the precursor adsorption state before and after replacing the above-mentioned ligand can occur due to the reaction between the precursor compound and the alkyl free halide on the above-mentioned substrate, wherein the above-mentioned precursor compound is formed by bonding a first halogen to a Group 4 central metal, and the above-mentioned alkyl free halide contains a second halogen for filling the ligand leaving site of the above-mentioned precursor compound.

[0172] As an example, the semiconductor substrate may include a deposited film formed by replacing a first halogen atom (F or Cl) on the central metal (M) of the chemical formula 1 with a second halogen atom (Br or I).

[0173] As an example, the film may be a multilayer structure of more than two layers, a multilayer structure of more than three layers, or a multilayer structure of two or three layers, as required. As a specific example, the multilayer film of the two-layer structure may be a structure of a lower film-middle film, and as a specific example, the multilayer film of the three-layer structure may be a structure of a lower film-middle film-upper film.

[0174] As a specific example, the deposited film may be an intermediate layer film (TiN electrode for DRAM or barrier film for NAND).

[0175] As an example, the above-mentioned lower layer film may include one or more selected from Si, SiO2, MgO, Al2O3, CaO, ZrSiO4, ZrO2, HfSiO4, Y2O3, HfO2, LaLuO2, Si3N4, SrO, La2O3, Ta2O5, BaO, and TiO2.

[0176] As an example, the upper layer film may include one or more selected from W and Mo.

[0177] Semiconductor Devices

[0178] According to the present invention, there is provided a semiconductor device including the above-mentioned semiconductor substrate.

[0179] As an example, the semiconductor device may be a low resistive metal gate interconnect, a high aspect ratio 3D metal-insulator-metal (MIM) capacitor, a DRAM trench capacitor, a 3D all-around gate (GAA), or a 3D NAND flash memory.

[0180] Below, preferred embodiments and drawings are proposed to help understand the present invention. Those skilled in the art will understand that the following embodiments and drawings are only used to illustrate the present invention, and various changes and modifications can be made within the scope of the scope of the present invention and technical ideas, and these deformations and modifications fall within the appended claims.

[0181] Example

[0182] TiCl4 was prepared separately as a precursor compound.

[0183] Separately, 5N HI was prepared as an activating agent.

[0184] The ALD deposition process is performed using the above-mentioned precursor compounds and activating agent and in accordance with the deposition process sequence of the present invention as one cycle.

[0185] The specific experimental methods of Example 1 and Comparative Example are as follows.

[0186] Example 1 (Example 1-1 to Example 1-8)

[0187] The precursor compound TiCl4 was placed in a tank and supplied to a separate vaporizer heated to 150°C at a flow rate of 0.05 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After TiCl4 vaporized in the vaporizer into a vapor phase was introduced into the deposition chamber using a Vapor Flow Controller (VFC) for 1 second, argon was supplied at 3000 sccm for 5 seconds to perform argon purge. At this time, the pressure in the reaction chamber was controlled to 2.5 Torr.

[0188] Then, 5N HI as an activator was placed in a tank and supplied to a vaporizer heated to 150°C at a flow rate of 0.05 g / min using a mass flow controller (MFC) at room temperature. After the activator vaporized in the vaporizer into a vapor phase was introduced into the deposition chamber loaded with the substrate for 2 seconds, argon gas was supplied at 3000 sccm for 8 seconds to perform argon purge. At this time, the pressure in the reaction chamber was controlled to 2.5 Torr.

[0189] Next, ammonia gas was introduced into the reaction chamber as a reactive gas at 1000 sccm for 3 seconds, and then argon gas was purged for 9 seconds. At this time, the substrate on which the deposited film was to be formed was heated to 460°C.

[0190] This process is repeated 200 to 400 times to form a Figure 1 8 self-limiting atomic layer deposition layers with the deposition thickness shown.

[0191] like Figure 1 As shown, the deposition thickness of the above deposited films is

[0192] The deposition thickness is the thickness of the deposited film measured by an ellipsometer, which is a device capable of measuring optical properties such as the thickness or refractive index of the deposited film by using the polarization properties of light.

[0193] In addition, the deposition rate increase rate (D / R (dep.rate) increase rate) was calculated for the above 8 deposited films. Specifically, the thickness of the deposited film is divided by the number of cycles to calculate the thickness of the deposited film deposited in each cycle, thereby calculating the deposited film growth rate reduction rate. Specifically, the calculation is performed using the above mathematical formula 1.

[0194] The average of the eight calculated sedimentation rate increases is

[0195] In addition, the resistivity of the above 8 deposited films was measured and the results are shown together in Figure 1 middle.

[0196] The above-mentioned resistivity is measured in consideration of the surface resistance measured using a surface resistance measuring instrument and the thickness measured using an ellipsometer.

[0197] Additionally, the deposition thickness is There are three kinds of resistivity values, namely 176 Ω·cm, 239 Ω·cm and 302 Ω·cm, and the calculated average value is 239 Ω·cm.

[0198] In addition, the density of the above 8 deposited films was measured using an X-ray reflectometry (XRR) device. The average value of the measured density of the 8 deposited films was 4.68 g / cm 3 .

[0199] In addition, the impurity contents of the above-mentioned 8 deposited films were measured.

[0200] Among them, SIMS (Secondary-ion mass spectrometry) was used to analyze H, C, NH, 18 O, Cl, Ti, etc. are measured.

[0201] Specifically, ion sputtering was used to dig into the deposited film in the axial direction, and the corresponding impurity counts at a sputtering time of 50 seconds, where there was less contamination in the surface layer of the substrate, were considered, and the impurity values ​​were confirmed in the SIMS graph.

[0202] The confirmed SIMS result value is Figure 2 Specifically, the Cl content in the 8 deposited films was calculated. - The average impurity level was 10.406 counts / second.

[0203] Available through Figure 1 Confirmed, except Cl - In addition, it is also possible to reduce O, Si, H, NH, metals, metal oxides, etc. remaining as process by-products.

[0204] Comparative Example 1

[0205] The same procedure as in Example 1 was repeated except that 5N HCl was used instead of 5N HI used as the activating agent in Example 1.

[0206] As a result, Cl impurities increase or very thin etching occurs.

[0207] For reference, when HCl or Cl2 is used on a TiN substrate and a plasma environment is formed or a high temperature condition corresponding thereto is proposed, there is a problem of dry etching TiN.

[0208] Comparative Example 2

[0209] The same procedure as in Example 1 was repeated except that 5N H1 as an activator was not used and a total of 10 deposited films were produced. The measurement results are collectively shown in FIG. Figure 1 as well as Figure 2 .

[0210] like Figure 1 As shown, the deposition thickness of the above deposited films is

[0211]

[0212] In addition, the increase rate of the deposition rate (D / R (dep. rate)) was calculated for the above 10 types of deposited films.

[0213] The average value of the above 10 sedimentation rate increases is calculated as

[0214] As a result, it was found that the performance was inferior to that of Example 1 by about 30%.

[0215] In addition, the resistivity of the above-mentioned 10 kinds of deposited films was measured.

[0216] like Figure 1 As shown, the resistivity of the above-mentioned deposited films are 515μΩ·cm, 517μΩ·cm, 592μΩ·cm, 650μΩ·cm, 800μΩ·cm, 802μΩ·cm, 890μΩ·cm, 900μΩ·cm, 970μΩ·cm and 11100μΩ·cm respectively, and the average value is calculated to be 715μΩ·cm, which is about 50% worse than that of Example 1.

[0217] Additionally, the deposition thickness is There are three kinds of resistivity values, namely 515 μΩ·cm, 517 μΩ·cm and 592 μΩ·cm, and the average value thereof is calculated to be 541 μΩ·cm.

[0218] In addition, the density of the above 10 deposited films was measured using an X-ray reflectometry (XRR) device. The average density of the 10 deposited films measured was calculated to be 5.03 g / cm 3 , it can be seen that it is about 9% worse than Example 1.

[0219] Additionally, the impurity contents of the above 10 deposited films were measured, and the confirmed SIMS result values ​​are shown together in a graph. Figure 2 Specifically, the average impurity content of Cl- in the 10 deposited films was calculated to be 31,638 counts / second, which is less than 50% of Example 1.

[0220] From the above results, it can be confirmed that compared with Comparative Example 1 which used an activator with the same ligand type as the precursor ligand and Comparative Example 2 which did not use an activator at all, the deposition thickness, deposition rate increase rate and resistivity of Examples 1 to 2 of the present invention which used an activator with a ligand type different from the precursor ligand were significantly improved, and the impurity reduction characteristics were also excellent.

[0221] In particular, compared with Comparative Example 2 which does not use the activator of the present invention, Example 1 which uses the activator of the present invention can confirm that the increase rate of the deposition rate of the deposited film per cycle and the density of the deposited film are respectively more than 10% higher, and the resistivity reduction rate is more than 50%, and the impurity reduction rate is more than 60%.

[0222] Therefore, when a compound whose ligand type is different from that of the precursor compound is used as the activator of the present invention, the thickness, deposition rate increase rate, density, and resistivity of the deposited film can be improved through the ligand replacement mechanism, and the impurity reduction characteristics are excellent, so that the deposited film can be effectively formed even on a substrate with a complex pattern.

Claims

1. An activator, wherein The activator comprises a halide not containing an alkyl group, and the halide not containing an alkyl group is used to replace a ligand of a precursor compound bonded to a Group 4 central metal.

2. The activator according to claim 1, wherein When the precursor compound contains a halogen, the halogen is referred to as a first halogen, and the halogen constituting the halide not containing an alkyl group is a second halogen different from the first halogen.

3. The activator according to claim 2, wherein The first halogen is a precursor having one or more ligands selected from fluorine, chlorine and bromine.

4. The activator according to claim 2, wherein The second halogen is at least one selected from iodine and bromine.

5. The activator according to claim 1, wherein The above-mentioned Group 4 central metal is titanium.

6. The activator according to claim 1, wherein The halide not containing an alkyl group is an iodine donor not containing an alkyl group, hydrogen iodide gas, hydrogen bromide gas, iodine ion or iodine radical.

7. The activator according to claim 1, wherein The above deposition adopts atomic layer deposition, plasma enhanced atomic layer deposition, chemical vapor deposition, plasma enhanced chemical vapor deposition, organometallic chemical vapor deposition or low pressure chemical vapor deposition.

8. A semiconductor substrate, wherein: The invention comprises a structure in which a ligand of a precursor compound is replaced by an activator on a substrate, wherein the activator comprises a halide not containing an alkyl group according to any one of claims 1 to 7.

9. The semiconductor substrate according to claim 8, wherein: The structure represented by the above chemical formula 1 is formed by reacting a precursor compound and a halide not containing an alkyl group on a substrate, wherein the precursor compound is formed by bonding a first halogen to a Group 4 central metal, and the halide not containing an alkyl group contains a second halogen for filling a ligand leaving position of the precursor compound.

10. The semiconductor substrate according to claim 8, wherein The semiconductor substrate includes a deposited film, and the deposited film includes a structure in which a substance derived from a reactant and a second halogen are bonded to a Group 4 central metal of Chemical Formula 1.

11. The semiconductor substrate according to claim 10, wherein The above-mentioned substances derived from reactants are H2O, H2O2, O2, O3, O free radical, D2, H2, H free radical, NH3, NO2, N2O, N2, N free radical, H2S or S.

12. The semiconductor substrate according to claim 10, wherein: The deposited film is a multi-layer structure of more than two layers.

13. The semiconductor substrate according to claim 10, wherein: The deposition thickness of the above deposited film is The resistivity of the deposited film is below 300 μΩ·cm, and the deposition rate is / cycle, the density of the deposited film is 4.0g / cm 3 As described above, the iodine atom count measured by secondary ion mass spectrometry was 50 counts / second or more.

14. A semiconductor device, wherein: Comprising the semiconductor substrate according to claim 8.

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