Method for purifying high-purity hydrogen iodide

Abstract

The present invention relates to a method for purifying ultra-high-purity hydrogen iodide. The present invention has the effect of providing a method for purifying ultra-high-purity hydrogen iodide having a purity of 99.999 to 99.999999999%, whereby only water of 10 ppm or less contained in high-purity hydrogen iodide can be removed to 0.1 ppm or less without decomposing or adsorbing the high-purity hydrogen iodide.

Description

Purification method of high-purity hydrogen iodide

[0001] The present invention relates to a method for purifying high-purity hydrogen iodide, and more specifically, to a method for purifying high-purity hydrogen iodide by removing moisture of 10 ppm or less contained in high-purity hydrogen iodide to 0.1 ppm or less using a predetermined adsorbent.

[0002] Hydrogen iodide and its aqueous solution (acid solution) have been prepared in various ways, such as the phosphorus pentoxide method, hydrazine method, hydrogen-iodine method, hydrogen sulfide method, and sulfur dioxide method.

[0003] The above phosphorus pentoxide method is a liquid-phase manufacturing method that reacts 57% HI(aq) with P2O5 and has the advantage of high productivity, but it has the disadvantage that it is difficult to capture the gas of the product hydrogen iodide and impurities such as H2O and O2 are introduced.

[0004] The above-mentioned hydrazine method is a liquid-phase manufacturing process in which iodine molecules react with hydrazine to generate hydrogen iodide and nitrogen gas. While it offers the advantage of high productivity, it has the disadvantages of difficulty in capturing the hydrogen iodide gas product and the introduction of impurities such as H2O and O2.

[0005] The above hydrogen-iodine method is a solid-gas reaction that produces hydrogen iodide alone through a photoreaction in which light is shone on iodine molecules in a hydrogen atmosphere. While it has the advantage of producing it in a high-purity gaseous state, it has the disadvantage of low productivity because the product inside the reactor must be continuously captured and removed to sustain the forward reaction due to the presence of a reverse reaction.

[0006] The above hydrogen sulfide method is a liquid-phase manufacturing method that obtains hydrogen iodide along with sulfur from hydrogen sulfide and iodine molecules. While it has the advantage of high productivity, it has the disadvantages of difficulty in capturing the gaseous hydrogen iodide product and the introduction of impurities such as H2O and O2.

[0007] The aforementioned sulfur dioxide method is a liquid-phase manufacturing process that obtains hydrogen iodide and sulfuric acid by reacting iodine molecules with sulfur dioxide in an aqueous solution. While this method also has the advantage of high productivity, it is difficult to capture the gaseous hydrogen iodide product, and impurities such as H2O and O2 are introduced. Furthermore, when using this method to deposit thin films, there is a problem in that the oxygen (O) impurity content inside the deposited film increases.

[0008] In addition, the hydrogen iodide produced in this way has a purity of 99 to 99.9% with a moisture content of 10 ppm or less even after undergoing a moisture purification process, and when used in harsh and sensitive semiconductor processes or semiconductor devices, it leaves oxygen species in the thin film. For example, when TiN is deposited, there is a fatal problem in that trace amounts of oxygen impurities originating from the moisture remain in the thin film, increasing resistivity by several to tens of percent.

[0009] In addition, adsorbents are used to remove moisture from hydrogen iodide for use in sensitive and harsh semiconductor processes or semiconductor devices, but depending on the type of adsorbent, there is a disadvantage that it decomposes the hydrogen iodide itself rather than just removing the moisture contained in high-purity hydrogen iodide (see Fig. 1 below).

[0010] Figure 1 below shows photographs of the adsorbents before and after purification of Example 1 and Comparative Examples 3 to 5. As shown in Figure 1 below, for example, when CaI2 is used, discoloration of the adsorbent is observed as hydrogen iodide is decomposed or adsorbed.

[0011] Therefore, research is needed on purification technology that can reduce only the contained moisture to 0.1 ppm or less without decomposing or adsorbing high-purity hydrogen iodide.

[0012] [Prior Art Literature]

[0013] [Patent Literature]

[0014] U.S. Patent No. 2,828,184

[0015] In order to solve the problems of the prior art as described above, the present invention aims to provide a method for purifying ultra-high purity hydrogen iodide with a purity of 99.999 to 99.99999999%, which can remove only moisture of 10 ppm or less contained in high purity hydrogen iodide to 0.1 ppm or less without decomposing or adsorbing high purity hydrogen iodide.

[0016] The above and other objectives of the present invention can all be achieved by the present invention described below.

[0017] To achieve the above objective, the present invention provides a method for purifying ultra-high purity hydrogen iodide, comprising the step of removing moisture of 10 ppm or less contained in high purity hydrogen iodide to 0.1 ppm or less without decomposing or adsorbing the high purity hydrogen iodide by using iodine, an iodide of an alkali metal, or an iodide of an alkaline earth metal as an adsorbent on the high purity hydrogen iodide.

[0018] The above adsorbent may be selected from iodine molecules (I2), lithium iodide (LiI), sodium iodide (NaI), potassium iodide (KI), and magnesium iodide (MgI2).

[0019]

[0020] The flow rate of high-purity hydrogen iodide per 1L of the above adsorbent may be in the range of 1 to 5000 mL / min.

[0021] The above purification step can be performed under temperature conditions of -50 to 110 ℃.

[0022] The above purification step can be performed under pressure conditions of 0.001 to 10 bar.

[0023] After the purification step above, a step of measuring the residual moisture amount using a quadrupole mass spectrometer (QMS) may be further included.

[0024] If the above residual moisture content does not satisfy 0.1 ppm or less, the above purification step may be performed again.

[0025] The above ultra-high purity hydrogen iodide may be within the range of purity 99.999 to 99.99999999%.

[0026] The above ultra-high purity hydrogen iodide can have a yield in the range of 98 to 99.99%.

[0027]

[0028] In addition, the present invention provides a method for manufacturing a thin film comprising the step of depositing a thin film using ultra-high purity hydrogen iodide with a purity of 99.999 to 99.99999999% and a moisture content of 0.1 ppm or less.

[0029] The process may include supplying the gas of the above-mentioned ultra-high purity hydrogen iodide to a chamber loaded with a substrate to substitute the ligands of a metal precursor adsorbed on the substrate; and supplying a reactant to the chamber to deposit a thin film.

[0030] The process of supplying the gas of the ultra-high purity hydrogen iodide to a chamber loaded with a substrate to replace the ligand of a metal precursor adsorbed on the substrate can be performed by a process of supplying a metal precursor to the chamber through a precursor supply unit to generate a precursor on the substrate, and a process of replacing the ligand of the metal precursor adsorbed on the substrate using the gas of the ultra-high purity hydrogen iodide supplied to the chamber.

[0031] The central metal of the above metal precursor may be one or more selected from Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Se, Y, Zr, Nb, Mo, Ru, Ph, In, Sn, Sb, Te, La, Ce, Hf, Ta, W, Re, Os, and Ir.

[0032] The ligand of the above metal precursor may be composed of one or more elements among C, N, O, H, Si, S, P, F, and Cl.

[0033] The above metal precursor may be a molecule having a molecular weight of 30 to 400 g / mol.

[0034]

[0035] The above reactants are oxidizing agents, nitrating agents, and reducing agents, and their specific substances may be oxygen, ozone, nitrogen, nitric oxide, nitrogen dioxide, hydrogen, ammonia, hydrazine or their derivatives, and mixed components such as nitrogen, oxygen, and hydrogen plasma.

[0036] The metal precursor, ultra-high purity hydrogen iodide, or reactant can each be transferred to the chamber by a method independently selected from among a vapor flow control (VFC) method applying a mass flow controller (MFC), a liquid flow control (LMFC) method applying a mass flow controller (MFC), or a liquid delivery system (LDS).

[0037] The carrier gas for moving the metal precursor, ultra-high purity hydrogen iodide, or reactant into the chamber may be one or more mixed gases selected from argon (Ar), nitrogen (N2), and helium (He).

[0038] The above deposition can be performed under temperature conditions of 10 to 1000 degrees.

[0039] The metal precursor, ultra-high purity hydrogen iodide, and reactants supplied into the chamber can each be supplied onto a substrate placed on a heating block through a showerhead.

[0040] The above thin film may be a metal film, an oxide film, or a nitride film.

[0041] The above deposition may be atomic layer deposition (ALD), plasma enhanced atomic layer deposition (PEALD), vapor deposition (CVD), plasma enhanced vapor deposition (PECVD), organometallic chemical vapor deposition (MOCVD), or low-pressure vapor deposition (LPCVD).

[0042] The ligand of the metal precursor adsorbed on the substrate is substituted with iodine derived from ultra-high purity hydrogen iodide, and the iodine may form a thin film through a reduction reaction with the reactant.

[0043] The above thin film manufacturing process may further include a process for separating the gas and liquid of a product containing hydrogen iodide.

[0044] In the case where the supply unit for supplying the above metal precursor is a nickel-plated gas cylinder, a self-assembled protective film in which a Ni-I atomic layer or a Ni-I2 molecular layer is formed on the uppermost part of the plated nickel can be formed to form the inner wall of the supply unit in a passivation state.

[0045] In the case where the supply unit for supplying the above reactant is a nickel-plated gas cylinder, a self-assembled protective film in which a Ni-I atomic layer or a Ni-I2 molecular layer is formed on the uppermost part of the plated nickel can be formed to form the inner wall of the supply unit in a passivation state.

[0046]

[0047] In addition, the present invention provides a semiconductor substrate characterized by including a thin film manufactured by the thin film manufacturing method described above.

[0048] The composition of the above thin film can be confirmed through XPS analysis.

[0049] The above thin film may have 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.

[0050] The above thin film may have a deposition thickness of 500 Å or less as measured by an ellipsometer.

[0051] In the case where the above thin film is a conductive thin film, the resistivity may be 300 μΩ·cm or less.

[0052] The density of the above thin film is 1.5 g / cm³ 3 It could be more than that.

[0053] The above thin film may have more than 50 counts / s of iodine atoms as measured by SIMS.

[0054] The above thin film is an oxide film, a nitride film, a metal film, or a sulfide film, and may be used as 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.

[0055]

[0056] In addition, the present invention provides a semiconductor device comprising the aforementioned semiconductor substrate.

[0057] According to the present invention, a purification method is provided to provide ultra-high purity hydrogen iodide by purifying high-purity hydrogen iodide with a moisture content of 10 ppm or less to a moisture content of 0.1 ppm or less without decomposition or adsorption.

[0058] The above ultra-high purity hydrogen iodide is suitable for use in sensitive or harsh semiconductor processes or semiconductor devices.

[0059] By applying ultra-high purity hydrogen iodide with extremely controlled moisture content to the thin film deposition process, it is possible to prevent corrosion or degradation and improve the crystallinity of the thin film, thereby improving the electrical properties of the thin film.

[0060] In addition, it has the effect of improving thin film productivity by improving the reaction deposition rate and appropriately increasing the thickness uniformity and density of the thin film.

[0061] In addition, it has the effect of improving the thickness uniformity of the thin film even in complex structures, thereby providing a semiconductor substrate of high purity and high reliability and a semiconductor device including the same.

[0062] Figure 1 shows photographs of the adsorbents before and after purification of Example 1 and Comparative Examples 3 to 5.

[0063] FIG. 2 is a flowchart of an apparatus used for purifying ultra-high purity hydrogen iodide, which further includes equipment for verifying a residual moisture content of 0.1 ppm or less in the present invention.

[0064] Figure 3 is a flowchart of a production apparatus used for purifying ultra-high purity hydrogen iodide and bottling and filling the purified ultra-high purity hydrogen iodide in the present invention.

[0065] Figure 4 is a diagram comparing the amount of residual moisture in purified hydrogen iodide according to the adsorbent used, based on the measurement results of a quadrupole mass spectrometer using equipment to confirm the amount of residual moisture of 0.1 ppm or less in Figure 3.

[0066] The light blue data corresponds to the left Y1 axis and represents the curve of changes in water (H2O) concentration; the closer it is to horizontal, the lower the water content.

[0067] The orange data corresponds to the right Y2 axis and represents the curve for changes in nitrogen (N2) concentration; the stepwise increase or decrease indicates a change in the injection amount of the injected nitrogen-containing gas. For example, when the injection amount of a 10 wt% HI / N2 mixed gas increases from 100 sccm to 500 sccm, the nitrogen intensity increases stepwise. Furthermore, a similar change in nitrogen intensity can be observed again when the injection amount of pure N2 increases or decreases from 100 sccm to 500 sccm.

[0068] Through this, it can be confirmed that the amount of injected iodine-containing nitrogen gas (HI / N2) changes, and even though the content of HI in the mixed gas has changed, the moisture (sky blue data curve) remains horizontal without increase or decrease, which means that there is no change in detected moisture, and thus the moisture content can be compared relatively.

[0069] The purification method of the ultra-high purity hydrogen iodide described herein is explained in detail below.

[0070] The term “high-purity hydrogen iodide” as used in this description refers to hydrogen iodide with a purity of 99 to 99.9% containing a moisture content of 10 ppm or less when hydrogen iodide is produced, unless otherwise specified.

[0071] The term “ultra-high purity hydrogen iodide” as used in this description refers to hydrogen iodide with a purity of 99.999 to 99.99999999%, obtained by removing moisture from the high purity hydrogen iodide to 0.1 ppm or less, unless otherwise specified.

[0072] Unless otherwise noted in this document, % is based on weight.

[0073]

[0074] While continuing research on purification technology to obtain ultra-high purity hydrogen iodide with controlled moisture content from high-purity hydrogen iodide, the inventors identified an adsorbent that does not decompose or adsorb hydrogen iodide while maintaining a residual moisture content of 0.1 ppm or less. Based on this, they devoted themselves to research on a purification method for ultra-high purity hydrogen iodide and completed the present invention.

[0075]

[0076] Specifically, the method for purifying high-purity hydrogen iodide according to the present invention is characterized by using an iodine molecule, an alkali metal iodide, or an alkaline earth metal iodide as an adsorbent for high-purity hydrogen iodide, and in this case, the moisture contained in the high-purity hydrogen iodide at a concentration of 10 ppm or less is removed to a concentration of 0.1 ppm or less without decomposing or adsorbing the high-purity hydrogen iodide.

[0077] In particular, when iodine is used as an adsorbent, a method is used to effectively remove a small amount (10 ppm or less) of moisture contained in hydrogen iodide without decomposing or adsorbing hydrogen iodide, and to effectively exclude crystal water captured in the above process, wherein the pressure inside the adsorption column is ideally 3 bar or less and the temperature is 1 ℃ or less, so that water is converted into ice particles and has the effect of physically isolating between purification processes by a particle filter.

[0078]

[0079] The above adsorbent may be one or more selected from iodine molecules (I2), lithium iodide (LiI), sodium iodide (NaI), potassium iodide (KI), and magnesium iodide (MgI2). In this case, the effect of removing moisture of 10 ppm or less contained in high-purity hydrogen iodide to 0.1 ppm or less can be maximized without decomposing or adsorbing high-purity hydrogen iodide.

[0080] The flow rate (purification rate) of high-purity hydrogen iodide per 1L of the above adsorbent can be, for example, in the range of 10 to 500,000 mL / min, and preferably in the range of 100 to 50,000 mL / min. In this case, the heat of adsorption and the heat of reaction are effectively cooled to prevent side reactions and maximize the purification effect.

[0081] The above high-purity hydrogen iodide can be provided in a liquefied gas state.

[0082] The above high-purity hydrogen iodide can be provided using an inert gas as a carrier gas.

[0083] The above inert gas may be argon, helium, or nitrogen gas unless otherwise specified.

[0084] The above purification step can be performed, for example, under temperature conditions of -50 to 110 ℃, and preferably, for example, under temperature conditions of -20 to 80 ℃, in which case the purification effect can be maximized.

[0085] The above purification step can be performed, for example, under pressure conditions of 0.001 to 10 bar, and preferably under pressure conditions of 1 to 5 bar, in which case the purification effect can be maximized.

[0086] After the purification step above, a step of measuring the amount of residual moisture using a quadrupole mass spectrometer (QMS) may be further included. In this case, not only is the amount of residual moisture detected more sensitively than a commercial moisture analyzer (laser scattering type), but the measurement limit is also high, making it possible to analyze high concentrations of moisture and ultra-trace amounts of moisture, which has the effect of confirming ultra-high purity purification.

[0087] If the measured residual moisture content does not satisfy 0.1 ppm or less, the purification step may be performed again, and the re-performance step may be repeated as many times as necessary. For example, it may be repeated 2 to 100 times.

[0088] The above ultra-high purity hydrogen iodide may have a purity range of 99.999% to 99.99999999%. In this case, it is desirable because thin film deposition effects, etc., can be effectively performed even in sensitive or harsh semiconductor processes or semiconductor devices.

[0089] The above ultra-high purity hydrogen iodide may have a yield in the range of 98 to 99.99%. In this case, it is desirable because it can effectively perform thin film deposition effects, etc., even in sensitive or harsh semiconductor processes or semiconductor devices.

[0090]

[0091] The above method for manufacturing a thin film using ultra-high purity hydrogen iodide can, for example, deposit a thin film using ultra-high purity hydrogen iodide with a purity of 99.999 to 99.99999999% and a moisture content of 0.1 ppm or less, but is not limited thereto.

[0092] Specifically, the process may include supplying the gas of the ultra-high purity hydrogen iodide to a chamber loaded with a substrate to substitute the ligand of a metal precursor adsorbed on the substrate; and supplying a reactant to the chamber to deposit a thin film.

[0093] The process of supplying the gas of the ultra-high purity hydrogen iodide to a chamber loaded with a substrate to replace the ligand of a metal precursor adsorbed on the substrate can be performed repeatedly using the process of supplying a metal precursor to the chamber through a precursor supply unit to generate a precursor on the substrate, and the process of replacing the ligand of the metal precursor adsorbed on the substrate using the gas of the ultra-high purity hydrogen iodide supplied to the chamber as a unit cycle.

[0094] The above ultra-high purity hydrogen iodide and metal precursor can be transferred to the deposition chamber by a method independently selected from among a vapor flow control (VFC) method applying a mass flow controller (MFC) method, a liquid mass flow controller (LMFC) method applying a mass flow controller (MFC) method, or a liquid delivery system (LDS).

[0095] When the above-mentioned ultra-high purity hydrogen iodide gas is supplied directly from the purification chamber to the deposition chamber without a separate separation process, separate capture or purification processes are omitted, thereby increasing the efficiency of the manufacturing process, i.e., economic feasibility, compared to conventional methods.

[0096] The ultra-high purity hydrogen iodide supplied into the deposition chamber can be supplied onto a substrate placed on a heating block through a showerhead.

[0097] The carrier gas for moving the above ultra-high purity hydrogen iodide into the deposition chamber may be one or more mixed gases selected from argon (Ar), nitrogen (N2) and helium (He).

[0098] The feeding time (sec) of the above ultra-high purity hydrogen iodide is preferably 0.001 to 30 seconds per cycle, more preferably 0.02 to 30 seconds, even more preferably 0.04 to 30 seconds, and even more preferably 0.05 to 30 seconds, and within this range, there are advantages such as high thin film growth rate, excellent step coverage, and economic efficiency.

[0099] In this description, the feeding time of the ultra-high purity hydrogen iodide is based on a flow rate of 1 to 500 sccm with a chamber volume of 15 to 20 L, and more specifically, based on a flow rate of 10 to 200 sccm with a chamber volume of 18 L.

[0100]

[0101] The above deposition chamber may be an atomic layer deposition (ALD) chamber, a plasma enhanced atomic layer deposition (PEALD) chamber, a vapor deposition (CVD) chamber, a plasma enhanced vapor deposition (PECVD) chamber, an organometallic chemical vapor deposition (MOCVD) chamber, or a low-pressure vapor deposition (LPCVD) chamber.

[0102] The above deposition chamber can load a substrate and then perform purging pretreatment.

[0103] In this description, purging corresponds to the purging process described below, 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 thin film growth rate per cycle is appropriately controlled, and deposition is performed as a single atomic monolayer or molecular layer, or close to it, which has an advantageous effect in terms of film quality.

[0104] The substrate loaded in the deposition chamber may include a semiconductor substrate such as a silicon substrate or silicon oxide.

[0105] The above substrate may further have a conductive layer or an insulating layer formed on its upper surface.

[0106] The above substrate can be maintained at 50 to 500 ℃, or 80 to 500 ℃.

[0107] The substrate may be heated to, for example, 50 to 500 ℃, specifically to 80 to 500 ℃, 100 to 800 ℃, or 200 to 500 ℃, and the metal precursor as well as ultra-high purity hydrogen iodide may be injected onto the substrate in an unheated or heated state, and depending on the deposition efficiency, it may be injected unheated and then the heating conditions may be adjusted during the deposition process. For example, it may be injected for 1 to 30 seconds onto a substrate heated to 300 to 600 ℃.

[0108]

[0109] Then, a process of substituting the ligand of the metal precursor is performed. This process can be carried out in one step, but can also be carried out in two or more steps to increase reaction efficiency. Specifically, it can be carried out by supplying a metal precursor to a deposition chamber through a precursor supply unit to generate a precursor on a substrate, and by substituting the ligand of the metal precursor adsorbed on the substrate using a gas of ultra-high purity hydrogen iodide in the deposition chamber.

[0110] The above precursor supply unit may be performed using container V1. The container V1 may be made of a material that does not react with the precursor, and may be, for example, a nickel-material high-pressure gas cylinder (steel, carbon steel, manganese steel, etc.), a SUS316L canister, a Hastelloy C22 canister, or a Teflon (PTFE or PFA) lining or coating canister.

[0111] Preferably, ultra-high purity hydrogen iodide can be filled into a nickel-plated gas cylinder, and at this time, a self-assembled protective film in which a Ni-I atomic layer or a Ni-I2 molecular layer is formed on the uppermost part of the plated nickel can be formed to form the inner wall of the container in a passivated state. The Ni-I or Ni-I2 passivation inner surface treatment performed on the nickel-plated high-pressure gas cylinder can be formed by injecting 10 to 1000 mL of ultra-high purity hydrogen iodide into a container before filling with ultra-high purity hydrogen iodide, and repeating vacuum purging to reach 10-5 Torr 1 to 10 times. When ultra-high purity hydrogen iodide is filled into a nickel-plated high-pressure gas cylinder treated with Ni-I or Ni-I2, metal, oxygen, and moisture contamination from the container can be prevented.

[0112] When ultra-high purity hydrogen iodide is filled without a Ni-I or Ni-I2 passivation inner surface treatment process, or when unpurified hydrogen iodide containing oxygen or moisture is filled, the NiO content may increase by more than 10% compared to when passivation treatment is performed.

[0113] Specifically, the process of generating a precursor on the substrate may apply various methods known as deposition techniques using conventional metal precursors, specifically including atomic layer deposition (ALD), plasma-enhanced atomic layer deposition (PEALD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), metal-organochemical chemical vapor deposition (MOCVD), or low-pressure chemical vapor deposition (LPCVD).

[0114] The above metal precursor may have a central metal (M) that is one or more selected from Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Se, Y, Zr, Nb, Mo, Ru, Ph, In, Sn, Sb, Te, La, Ce, Hf, Ta, W, Re, Os, and Ir.

[0115] The above metal precursor may have a ligand composed of one or more elements of C, N, O, H, Si, S, P, F, and Cl, and specifically may be chlorine, a cyclic compound, an alkylamine, or an alkoxy group.

[0116] The above ligands are, for example, L1, L2, L3, L4, L 1' , L 2' , L 3' , L 4' As such, they can be the same or different from each other.

[0117] For example, the above L1 is -guanidiate, -amidinate, -triazenide, -iPr, -tBu, -Cp, -Ph, or -OR, and R is -CH3, -CH2CH3, -iPr, or -tBu, and L2, L3, and L4 can each independently be -H, -CH3, -CH2CH3, -OH, -NRH, or -NR2.

[0118] As another example, L1 and L2 may each independently be -iPr, -tBu, -Cp, -Ph, or -OR, and R may be -H, -CH3, -CH2CH3, -iPr, or -tBu, and L3 and L4 may each independently be -H, -CH3, -CH2CH3, -OH, -NRH, or -NR2.

[0119] As another example, L1, L2, and L3 may each independently be -iPr, -tBu, -Cp, -Ph, or -OR, R may be -H, -CH3, -CH2CH3, -iPr, or -tBu, and L4 may be -H, -CH3, -CH2CH3, -OH, -NRH, or -NR2.

[0120] As another example, the above L 1' , L 2' , L 3' , L 4' Each is independently -iPr, -tBu, -Cp, -Ph, or -OR, and R can be -H, -CH3, -CH2CH3, -iPr, or -tBu.

[0121] The above ligands can form symmetric or asymmetric structures.

[0122] Unless otherwise noted in this description, Pr represents a propyl group and Bu represents a butyl group.

[0123] In the case of the above metal precursor having a vapor pressure of 1 mTorr to 100 Torr at 25 ℃, the effect of filling the leaving site of the aforementioned ligand can be maximized.

[0124] In the present invention, the metal precursor can be introduced into a chamber by mixing it with, for example, a non-polar solvent, and in this case, there is an advantage that the viscosity or vapor pressure of the metal precursor can be easily controlled.

[0125] The above non-polar solvent may preferably be one or more selected from the group consisting of alkanes and cycloalkanes, and in this case, there is an advantage of having improved step coverage even when the deposition temperature is increased during thin film formation while containing an organic solvent that has low reactivity and solubility and is easy to manage moisture.

[0126] As a more preferred example, the nonpolar solvent may include C1 to C10 alkanes or C3 to C10 cycloalkanes, preferably C3 to C10 cycloalkanes, in which case there is an advantage of low reactivity and solubility and easy moisture management.

[0127] In this description, C1, C3, etc. refer to the number of carbon atoms.

[0128] The above cycloalkane may preferably be a C3 to C10 monocycloalkane, and among the monocycloalkanes, cyclopentane is preferred in the vapor deposition process as it is liquid at room temperature and has the highest vapor pressure, but is not limited thereto.

[0129] The above non-polar solvent has, for example, a solubility in water (at 25°C) of 200 mg / L or less, preferably 50 to 400 mg / L, more preferably 135 to 175 mg / L, and within this range, has the advantage of low reactivity to metal precursors and easy moisture management.

[0130] In this description, solubility is not particularly limited when measured according to standard measurement methods or criteria commonly used in the technical field to which the present invention belongs, and, for example, a saturated solution can be measured by the HPLC method.

[0131] The above non-polar solvent may preferably comprise 5 to 95 weight% based on the total weight of the metal precursor and the non-polar solvent combined, more preferably 10 to 90 weight%, even more preferably 40 to 90 weight%, and most preferably 70 to 90 weight%.

[0132] If the content of the above non-polar solvent is added in excess of the upper limit, it causes impurities, increasing resistance and impurity levels within the thin film; and if the content of the above organic solvent is added below the lower limit, there is a disadvantage in that the effect of improving step coverage and reducing impurities due to solvent addition is small.

[0133] The above metal precursor may use molecules with a molecular weight in the range of 30 to 400 g / mol, and in this case, it can provide an effective vapor pressure and facilitate mass transfer.

[0134] The above metal precursor may be used as an example of TiCl4, SiCl4, Si2Cl6, MoCl5, MoO2Cl2, NbCl5, CpZr, CpHf, Al(CH3)3, etc.

[0135] According to a process of replacing the ligands of a metal precursor adsorbed on the substrate using ultra-high purity hydrogen iodide gas supplied to the deposition chamber, the ligands of the metal precursor can be replaced with iodine atoms (I) by the ultra-high purity hydrogen iodide. In this case, the leaving group of the precursor adsorbed on the substrate is effectively changed to improve the reaction rate and appropriately lower the thin film growth rate, thereby having the effect of significantly improving step coverage, resistivity, and thickness uniformity of the thin film even when forming a thin film on a substrate having a complex structure.

[0136] The process can be performed under conditions where the molar ratio of ultra-high purity hydrogen iodide to the metal precursor is 10:1 to 1:1, the deposition temperature is 10 to 1000 ℃, and the deposition pressure is 0.1 to 20 Torr.

[0137] The amount of the metal precursor introduced into the deposition chamber (mg / cycle) is such that the ratio of the hydrogen iodide to the amount of the metal precursor introduced into the deposition chamber (mg / cycle) is, for example, 1:1 to 1:20, preferably 1:1 to 1:15, more preferably 1:1 to 1:10, and within this range, the effect of improving step coverage and the effect of reducing process by-products are significant.

[0138] The metal precursor can be transferred from the precursor supply unit to the deposition chamber via a stream, and the stream may apply a method independently selected from among a vapor flow control (VFC) method applying a mass flow controller (MFC), a flow control method applying a liquid mass flow controller (LMFC), or a liquid delivery system (LDS).

[0139] In addition, in the case of gaseous transfer, it can be transferred to the chamber after passing through the vaporizer.

[0140] The carrier gas for moving the metal precursor into the deposition chamber may be one or more mixed gases selected from argon (Ar), nitrogen (N2) and helium (He).

[0141] The metal precursor supplied into the deposition chamber can be supplied onto a substrate placed on a heating block through a showerhead.

[0142]

[0143] Then, a process for depositing a thin film can be performed, and the process may consist of supplying a reactant from a reactant supply unit to the chamber to deposit a thin film.

[0144] The above reactants may be, for example, oxygen, ozone, nitrogen, nitric oxide, nitrogen dioxide, hydrogen, ammonia, hydrazine, or derivatives thereof.

[0145] The above reactant supply unit may be performed using vessel V6. Vessel V6 may be made of a material that does not react with the precursor, and may be, for example, a nickel-based high-pressure gas cylinder (steel, carbon steel, manganese steel, etc.), a SUS316L canister, a Hastelloy C22 canister, or a Teflon (PTFE or PFA) lining or coating canister.

[0146] Preferably, ultra-high purity hydrogen iodide can be filled into a nickel-plated gas cylinder, and at this time, a self-assembled protective film in which a Ni-I atomic layer or a Ni-I2 molecular layer is formed on the uppermost part of the plated nickel can be formed to form the inner wall of the container in a passivation state.

[0147] The above reactants can be transferred to the deposition chamber via a stream from the reactant supply unit, and the stream can be transferred to the deposition chamber by a method independently selected from a vapor flow control (VFC) method applying a gas phase flow control (Mass Flow Controller; MFC), a liquid phase flow control (Mass Flow Controller; LMFC) method applying a liquid flow control (License Mass Flow Controller; LMFC), or a liquid delivery system (Liquid Delivery System; LDS).

[0148] In the case of transferring via the gas phase here, it can be transferred to the deposition chamber after passing through the vaporizer.

[0149] The carrier gas for moving the above reactants into the deposition chamber may be one or more mixed gases selected from argon (Ar), nitrogen (N2) and helium (He).

[0150] The reactants supplied into the deposition chamber can be supplied onto a substrate placed on a heating block through a showerhead.

[0151]

[0152] The iodine bound to the precursor by the above ligand exchange forms a thin film through a reduction reaction with the above reactant.

[0153] The above thin film can be referred to as a thin film, and specific examples may include a metal film, an oxide film, or a nitride film.

[0154] The deposition thickness of the above thin film measured by SIMS may be 170 Å or less, or 100 to 170 Å.

[0155] The resistivity of the thin film may be 300 μΩ·cm or less, or 150 to 300 μΩ·cm, and electrical conductivity may be improved within the above range.

[0156] The deposition rate of the above thin film may be 0.34 Å / cycle or higher, or 0.34 to 0.535 Å / cycle.

[0157] The density of the above thin film may be 4.8 g / cm³ or higher, or 4.8 to 5.3 g / cm³.

[0158] The above thin film may have a deposition rate increase rate represented by the following mathematical formula 1 of 10% or more, specifically 12.5% ​​or more, and preferably 15% or more. In this case, the growth rate of the thin film is significantly reduced, so even when applied to a substrate with a complex structure, the uniformity of the thin film is ensured, and the step coverage is greatly improved. In particular, it is possible to deposit it at a thin thickness, and it can provide the effect of improving O, Si, metal, metal oxides that remained as process by-products, and even carbon residues that were difficult to reduce in the past.

[0159] [Mathematical Formula 1]

[0160] Sedimentation rate growth rate = [(DR f ) / (DR i )]×100

[0161] (In the above formula, DR (Deposition rate, Å / cycle) is the rate at which the thin film is deposited. In the deposition of a thin film formed from a precursor and a reactant, DR i (Initial deposition rate) is the deposition rate of a thin film formed without the addition of hydrogen iodide. DR f The final deposition rate is the deposition rate of the thin film formed by introducing hydrogen iodide during the above-mentioned process. Here, the deposition rate (DR) is a value measured using an ellipsometer for thin films with a thickness of 1 to 30 nm under room temperature and atmospheric pressure conditions, and is expressed in units of Å / cycle.

[0162] In the above mathematical formula 1, the thin film growth rate per cycle when ultra-high purity hydrogen iodide is used and when it is not used refers to the thin film deposition thickness per cycle (Å / cycle), i.e., the deposition rate, and the deposition rate can be obtained as an average deposition rate by measuring the final thickness of a thin film with a thickness of 1 to 30 nm under room temperature and atmospheric pressure conditions using ellipsometery, for example, and dividing it by the total number of cycles.

[0163] In the above mathematical formula 1, "when ultra-high purity hydrogen iodide is not used" refers to a case in which a thin film is manufactured by adsorbing only a metal precursor onto a substrate in a thin film deposition process, and a specific example refers to a case in which a thin film is formed by omitting the step of adsorbing hydrogen iodide and the step of purging unadsorbed hydrogen iodide in the above thin film formation method.

[0164] The above thin film formation method can be carried out, for example, at a deposition temperature in the range of 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 500°C, and even more preferably at a deposition temperature in the range of 220 to 450°C, and within this range, it has the effect of growing a thin film of excellent quality while realizing process characteristics.

[0165] The above thin film formation method can be carried out, for example, at a deposition pressure in the range of 0.01 to 20 Torr, and preferably at a deposition pressure in the range of 0.1 to 20 Torr, which has the effect of obtaining a thin film of uniform thickness within this range.

[0166] In this description, the deposition temperature and deposition pressure may be measured as the temperature and pressure formed within the deposition chamber, or as the temperature and pressure applied to the substrate within the deposition chamber.

[0167] The above thin film formation method comprises, for example, a step of adsorbing a metal precursor onto a substrate, a step of purging the unadsorbed metal precursor, a step of supplying hydrogen iodide onto the substrate on which the precursor is adsorbed, a step of purging the unadsorbed hydrogen iodide, a step of supplying a reactant, and a step of purging residual reactants and by-products as a unit cycle, and the unit cycle may be repeated to form a thin film of a desired thickness.

[0168] The above thin film forming method may repeat the unit cycle 1 to 99,999 times as needed, preferably 10 to 10,000 times, more preferably 50 to 5,000 times, and even more preferably 100 to 2,000 times, and within this range, the desired thin film thickness can be obtained while sufficiently achieving the effect intended to be achieved in the present invention.

[0169]

[0170] Each of the aforementioned processes may include a purging process as needed before or after its commencement. This purging process may be performed selectively as needed using a purging gas provided from an inert gas supply unit. That is, the purging process is performed to remove materials injected into the deposition chamber if they remain in each process or if excessive by-products are generated, and one or more mixed gases selected from argon (Ar), nitrogen (N2), and helium (He) supplied from the inert gas supply unit may be used.

[0171] The above purging process may be included one or more times.

[0172] In the above purging process, the amount of purge gas introduced into the deposition chamber is not particularly limited as long as it is sufficient to remove the unadsorbed or unreacted material, but for example, it may be 10 to 100,000 times the volume of the metal precursor introduced into the deposition chamber, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times. Within this range, the unadsorbed material can be sufficiently removed to form a thin film evenly and prevent deterioration of the film quality. Here, the amounts of the purge gas and the metal precursor introduced are each based on one cycle, the volume of the metal precursor refers to the volume of vaporized metal precursor vapor, and the volume of hydrogen iodide refers to the volume of vaporized hydrogen iodide vapor.

[0173] For example, when the above ultra-high purity hydrogen iodide is injected at a flow rate of 100 sccm and an injection time of 0.5 sec (per cycle), and when a purge gas is injected at a flow rate of 3000 sccm and an injection time of 5 sec (per cycle) in the step of purging the unadsorbed ultra-high purity hydrogen iodide, the amount of purge gas injected is 300 times the amount of hydrogen iodide injected.

[0174] In the present invention, purging 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, and within this range, the thin film growth rate per cycle is appropriately controlled, and deposition is performed as an atomic monolayer or close to it, which has an advantageous effect in terms of film quality.

[0175] The stream can be transferred from the above-mentioned inert gas supply unit to the deposition chamber, and the stream can be transferred by a method independently selected from a vapor flow control (VFC) method applying a gas phase flow control (Mass Flow Controller; MFC), a liquid phase flow control (Mass Flow Controller; MFC) method applying a liquid phase flow control (Liquid Mass Flow Controller; LMFC), or a liquid delivery system (Liquid Delivery System; LDS).

[0176] Furthermore, one or more mixed gases selected from argon (Ar), nitrogen (N2), and helium (He) supplied from the inert gas supply unit may be transferred to the precursor supply unit or the reactant supply unit as needed, and in this case, the reaction efficiency can be improved by assisting in the transfer of the precursor or reactant to the deposition chamber.

[0177] The above thin film manufacturing method may further include a process for separating the product containing hydrogen iodide into gas and liquid as needed, in which case a gas-liquid separator (not shown) may be further provided. The gas-liquid separator may be a temperature-based separation device in the form of a cold trap. In the above method, oxygen can be easily removed at -200 to -180°C, crystallized using the freezing point of iodine at -51°C or lower, and pure iodine can be recovered through filtration, and O2, CO, CO2, NO2, N2O, etc. can be effectively removed.

[0178] The gas-liquid separation process may include liquefaction and filling or bottling processes. The liquefaction method may involve cooling to -35°C or lower, which is the boiling point of hydrogen iodide, to liquefy and collect liquid, or applying pressure at room temperature to compress, liquefy, and collect liquid.

[0179]

[0180] When the injection and purging of the metal precursor and ultra-high purity hydrogen iodide, and the injection and purging of the reactant are defined as one cycle, the following four conditions can all be satisfied: 1) the deposition thickness of the thin film measured by an ellipsometer is 500 Å or less, 2) the resistivity of the thin film is 300 μΩ·cm or less, 3) the deposition rate is 0.34 Å / cycle or more, and 4) the density of the thin film is 4.5 g / cm3 or more.

[0181] The above thin film may be a metal film, an oxide film, a nitride film alone, or a nitride film including a sulfide film or a chalcogenide, and in this case, the effect intended to be achieved in the present invention can be sufficiently obtained.

[0182] The above thin film can be utilized in semiconductor devices not only as a diffusion barrier film commonly used, but also as an etching stop film, electrode film, dielectric film, gate insulating film, block oxide film, or charge trap.

[0183] The deposition thickness of the thin film measured by an ellipsometer may be 500 Å or less, or 2 to 300 Å, and more preferably 5 to 250 Å.

[0184] The thin film may have a resistivity of 300 μΩ·cm or less, or 10 to 300 μΩ·cm, and more preferably 30 to 200 μΩ·cm.

[0185] The density of the above thin film may be 4.5 g / cm³ or more, or 4.5 to 5.5 g / cm³.

[0186] The above thin film may have more than 50 counts / s of iodine atoms as measured by SIMS.

[0187]

[0188] The present invention also provides a semiconductor substrate, wherein the semiconductor substrate is manufactured by the thin film formation method of the present invention or comprises said thin film, and in such case, the step coverage and thickness uniformity of the thin film are significantly excellent, and the density and electrical properties of the thin film are excellent.

[0189] As described above, the change in the adsorption state of the precursor before and after ligand exchange can be formed on the substrate by a reaction between a halogen metal precursor and a hydrogen iodide containing a halogen to fill the ligand leaving site of the metal precursor.

[0190] For example, the semiconductor substrate may include a thin film formed by undergoing a process in which a ligand bonded to a central metal of a metal precursor is substituted with iodine constituting hydrogen iodide, and then the site from which the iodine was removed is substituted with nitrogen (N), etc.

[0191] The above thin film may, for example, have 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, as needed. A specific example of the above two-layer multilayer film may be a lower layer-middle layer structure, and a specific example of the above three-layer multilayer film may be a lower layer-middle layer-upper layer structure.

[0192] The above thin film may be, as a specific example, a medium film (TiN electrode for DRAM or barrier film for NAND).

[0193] The above lower layer may comprise, for example, 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, TiO2, Ta2O5, and RuO2.

[0194] The above upper layer may comprise, for example, one or more types selected from the group consisting of W and Mo.

[0195]

[0196] According to the present invention, a semiconductor device comprising the aforementioned semiconductor substrate can be provided.

[0197] The above semiconductor device may be, for example, a low resistive metal gate interconnect, a high aspect ratio 3D metal-insulator-metal (MIM) capacitor, a DRAM trench capacitor, a 3D Gate-All-Around (GAA), or a 3D NAND flash memory.

[0198]

[0199] Hereinafter, 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 is obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, and that such variations and modifications fall within the scope of the appended claims.

[0200]

[0201] [Example]

[0202] High-purity hydrogen iodide with a moisture content of 10 ppm or less was prepared, the types shown in Table 1 below were prepared as adsorbents, TiCl4 was prepared as a metal precursor, and NH3 was prepared as a reactant.

[0203]

[0204] The specific experimental methods for Examples 1 to 4 and Comparative Examples 1 to 6 are as follows.

[0205] Examples 1 to 4

[0206] High-purity hydrogen iodide was purified according to the apparatus flowchart shown in Fig. 3.

[0207] Figure 3 below is a flowchart of an apparatus used for purifying ultra-high purity hydrogen iodide, which further includes equipment for verifying residual moisture content in units of 0.1 ppm or less in the present invention.

[0208] Specifically, liquefied gas of high-purity hydrogen iodide or compressed gas mixed with high-purity hydrogen iodide and nitrogen gas was injected into gas cylinder 1 of FIG. 3, compressed nitrogen gas was injected into gas cylinder 2, and the packing column was filled with the types of adsorbents disclosed in Table 1 below.

[0209] At this time, the packing column was prepared using SUS304, SUS316L, Hastelloy C22, or corrosion-resistant materials.

[0210] Then, purification was performed under the conditions shown in Table 1 below, and the amount of residual moisture was measured using a Quadrupole Mass Spectrometer (QMS).

[0211] The results of the above residual moisture content analysis are shown in Figure 4 below.

[0212] When the residual moisture content was confirmed to be 0.1 ppm or less, ultra-high purity hydrogen iodide was transferred to a thin film deposition chamber (not shown) loaded with a substrate.

[0213]

[0214] Comparative Examples 1 to 6

[0215] High-purity hydrogen iodide was purified according to the apparatus flowchart shown in Figure 2.

[0216] Figure 2 below is a flowchart of a conventional apparatus used for purifying hydrogen iodide.

[0217] Specifically, liquefied gas of high-purity hydrogen iodide or compressed gas mixed with high-purity hydrogen iodide and nitrogen gas was injected into gas cylinder 1 of FIG. 2, compressed nitrogen gas was injected into gas cylinder 2, and the packing column was filled with the types of adsorbents disclosed in Table 1 below.

[0218] At this time, the packing column was prepared using SUS304, SUS316L, Hastelloy C22, or corrosion-resistant materials.

[0219] Then, purification was performed under the conditions shown in Table 1 below, and the product was transferred to gas cylinder 3.

[0220] The amount of residual moisture in the iodide gas transferred to the above gas cylinder 3 was measured using a quadrupole mass spectrometer (QMS).

[0221] The results of the above residual moisture content analysis are shown together in Figure 4 below.

[0222]

[0223] [Test Example 1]

[0224] First, the decomposition or adsorption capacity of hydrogen iodide for each adsorbent used in Examples 1 to 4 and Comparative Examples 1 to 6 was confirmed.

[0225] Specifically, the state before and after purification for each type of adsorbent is shown in Figure 1 below.

[0226] Figure 1 below corresponds to photographs of the adsorbents before and after purification of Example 1 and Comparative Examples 3 to 5. As shown in Figure 1 below, in Example 1 using iodine molecules (I2), no discoloration occurred before or after purification, whereas in Comparative Examples 3 to 5, discoloration was observed. From this, it was possible to confirm that iodine molecules (I2) are adsorbents unrelated to the decomposition or adsorption of hydrogen iodide.

[0227]

[0228] [Test Example 2]

[0229] The results of the moisture analysis of hydrogen iodide according to the adsorbents used in Examples 1 to 4 and Comparative Examples 1 to 6 are shown in Table 1 and Figure 4 below.

[0230] Figure 4 below is a diagram comparing the amount of residual moisture in purified hydrogen iodide according to the adsorbent used, based on the analysis results using equipment to confirm the amount of residual moisture of 0.1 ppm or less in Figure 3 above.

[0231] Experiment Example Experiment Conditions Moisture Analysis Deposition Result Adsorbent Temperature Pressure QMS GPC Resistivity (°C) (bar) △I (×10 -11)(Å / cycle)(μΩ·cm) Comparative Example 1--2030.800.4760 Comparative Example 2 NiI2-2030.330.32205 Comparative Example 3 NiO / MgO2 / SiO2(1:1:1)-2030.200.31148 Comparative Example 4 Silica blue (Co ~5wt%)-2030.020.27215 Comparative Example 5 M / S (4A)-2030.0140.28155 Comparative Example 6 Silica gel-2030.0060.3140 Example 1 Iodine (I2)-2030.0020.4948 Example 2 Iodine (I2)2030.0040.4851 Example 3 CaI2-2030.010.4192

[0232] As shown in Table 1 above and Figure 4 below, in the case of Examples 1 to 2 using iodine molecules (I2) and Examples 3 to 4 using CaI2, the moisture analysis results showed a residual moisture content of 0.1 ppm or less. On the other hand, Comparative Example 1 was 0.8 ppm when not used, Comparative Example 2 using NiI2 showed a residual moisture content of 0.33, and Comparative Example 3, which mixed NiO:MgO2:SiO2 in a weight ratio of 1:1:1, showed a residual moisture content of 0.2 ppm, which was not suitable.

[0233] On the other hand, Comparative Example 4 using silica blue (containing 5 wt% cobalt) had a residual moisture content of 0.02 ppm, and molecular sieve (M / S) 4A (=4 Comparative Example 5, which used ), had a residual moisture content of 0.014 ppm, and Comparative Example 6, which used silica gel, had a residual moisture content of 0.006 ppm; although the residual moisture content alone was 0.1 ppm or less, as seen in Test Example 1 mentioned above, it was confirmed that hydrogen iodide was decomposed or adsorbed, such as by discoloration before and after purification, and was determined to be unsuitable.

[0234]

[0235] [Test Example 3]

[0236] Thin film deposition was performed for 200 to 400 cycles under the deposition conditions according to Table 2 below, and the deposition rate and resistivity were measured and shown together in Table 1 above.

[0237] * Measurement of Deposition Rate (GPC): The deposition rate (GPC) was measured for each of the obtained thin films of Examples 1 to 4 and Comparative Examples 1 to 6 in the following manner. Specifically, the deposition rate of thin films with thicknesses of 3 to 30 nm was measured using an ellipsometer, and the unit used is Å / cycle.

[0238] *Resistivity: After measuring the sheet resistance using the 4-probe measurement method, the resistivity value was calculated using the measured thickness.

[0239] Substrate Temperature Sequence (Gas Injection Amount: *HI 300 sccm, **NH3, 1000 sccm)(°C)TiCl4N2 * HIN2 ** NH3N2550265939

[0240] As shown in Table 1 above, both the deposition rate and resistivity were improved in Examples 1 to 4, which used an adsorbent that does not decompose or adsorb hydrogen iodide according to the present invention.

[0241] Accordingly, according to the present invention, by providing a purification method that purifies high-purity hydrogen iodide with a moisture content of 10 ppm or less to 0.1 ppm or less without decomposition or adsorption, thereby providing ultra-high-purity hydrogen iodide, the ultra-high-purity hydrogen iodide with extremely controlled moisture content is applied to a thin film deposition process to prevent corrosion or degradation and improve the crystallinity of the thin film, thereby improving the electrical properties of the thin film. Furthermore, it was confirmed that the reaction deposition reaction rate can be improved, and the thickness uniformity and density of the thin film can be appropriately increased to improve thin film productivity, and even with a complex structure, the thickness uniformity of the thin film can be improved to provide a semiconductor substrate of high purity and high reliability and a semiconductor device including the same.

Claims

1. A method for purifying ultra-high purity hydrogen iodide comprising the step of using iodine, an alkali metal iodide, or an alkaline earth metal iodide as an adsorbent on high purity hydrogen iodide to remove moisture of 10 ppm or less contained in high purity hydrogen iodide to 0.1 ppm or less without decomposing or adsorbing the high purity hydrogen iodide.

2. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized in that the adsorbent is one or more selected from iodine molecule (I2), lithium iodide (LiI), sodium iodide (NaI), potassium iodide (KI), and magnesium iodide (MgI2).

3. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized in that the flow rate of high purity hydrogen iodide per 1L of the adsorbent is within the range of 1 to 5000 mL / min.

4. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized by performing the purification step under temperature conditions of -50 to 110 ℃.

5. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized in that the above purification step is performed under pressure conditions of 0.001 to 10 bar.

6. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized by further including the step of measuring the amount of residual moisture using a quadrupole mass spectrometer (QMS) after the purification step.

7. In Paragraph 6, A method for purifying ultra-high purity hydrogen iodide, characterized by repeating the purification step if the measured residual moisture content does not satisfy 0.1 ppm or less.

8. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized in that the ultra-high purity hydrogen iodide has a purity within the range of 99.999 to 99.99999999%.

9. In Paragraph 1, A method for purifying ultra-high purity hydrogen iodide, characterized in that the above ultra-high purity hydrogen iodide has a yield within the range of 98 to 99.99%.

10. A method for manufacturing a thin film comprising the step of depositing a thin film using ultra-high purity hydrogen iodide with a purity of 99.999 to 99.99999999% and a moisture content of 0.1 ppm or less.

11. In Paragraph 10, A method for manufacturing a thin film characterized by comprising: a process of supplying the gas of the above-mentioned ultra-high purity hydrogen iodide to a chamber loaded with a substrate to substitute the ligand of a metal precursor adsorbed on the substrate; and a process of supplying a reactant to the chamber to deposit a thin film.

12. In Paragraph 10, A method for manufacturing a thin film, characterized by repeating, as a unit cycle, the process of supplying the above-mentioned ultra-high purity hydrogen iodide gas to a chamber loaded with a substrate to replace the ligand of a metal precursor adsorbed on the substrate, the process of supplying a metal precursor to the chamber through a precursor supply unit to generate a precursor on the substrate, and the process of replacing the ligand of the metal precursor adsorbed on the substrate using the ultra-high purity hydrogen iodide gas supplied to the chamber.

13. In Paragraph 10, A method for manufacturing a thin film, characterized in that the central metal of the metal precursor is one or more selected from Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Se, Y, Zr, Nb, Mo, Ru, Ph, In, Sn, Sb, Te, La, Ce, Hf, Ta, W, Re, Os, and Ir, the ligand of the metal precursor is composed of one or more elements selected from C, N, O, H, Si, S, P, F, and Cl, and the metal precursor is a molecule having a molecular weight of 15 to 300 g / mol.

14. In Paragraph 11, A method for manufacturing a thin film characterized in that the above-mentioned reactants are oxidizing agents, nitrating agents, and reducing agents, and the specific substances thereof are oxygen, ozone, nitrogen, nitric oxide, nitrogen dioxide, hydrogen, ammonia, hydrazine or derivatives thereof, and mixed components such as nitrogen, oxygen, and hydrogen plasma.

15. In Paragraph 10, A method for manufacturing a thin film characterized by further including a process for separating the gas and liquid of a product containing hydrogen iodide in the above-mentioned thin film manufacturing process.

16. In Paragraph 10 or 11, A method for manufacturing a thin film characterized by forming a self-assembled protective film in which a Ni-I atomic layer or a Ni-I2 molecular layer is formed on the uppermost portion of the plated nickel, thereby forming the inner wall of each supply section in a passivation state, when the supply section for supplying the metal precursor or the supply section for supplying the reactant is a nickel-plated gas cylinder.

17. A semiconductor substrate characterized by including a thin film manufactured by the thin film manufacturing method of claim 10.

18. A semiconductor device comprising the semiconductor substrate of claim 17.

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