Azeotrope, thin film deposition method, thin film prepared thereby, semiconductor substrate, and semiconductor device

Abstract

The present invention relates to an azeotrope, a thin film deposition method, a thin film prepared thereby, a semiconductor substrate and a semiconductor device, and according to the present invention, there are provided an azeotrope, a thin film deposition method using the same, a thin film prepared thereby, a semiconductor substrate and a semiconductor device, etc., in which, in a precursor compound used to form a thin film on a substrate, a precursor compound having high self-ignition is formulated with a volatility modifier to be provided as an azeotrope, so that the volatility of the precursor compound can be controlled, not only to be easily injected into a chamber in a vapor state, but also to reduce a deposition speed, so that a thin film having a relatively thin thickness can be easily and accurately deposited, and impurities are not left in the thin film.

Description

Technical Field

[0001] This invention relates to an azeotropic mixture, a thin film deposition method thereon, thin films prepared therefrom, semiconductor substrates, and semiconductor devices. More specifically, it relates to an azeotropic mixture, a thin film deposition method using the same, and thin films, semiconductor substrates, and semiconductor devices prepared therefrom, wherein a precursor compound with high self-ignition properties is formulated with a volatility modifier in a precursor compound used to form a thin film on a substrate to provide an azeotropic mixture. This allows for control of the volatility of the precursor compound, facilitating its injection into the chamber in a vapor state and reducing the deposition rate. This enables the precise deposition of thinner films without leaving any impurities in the film. Background Technology

[0002] Aluminum or zinc precursors are widely used in fields such as semiconductors, displays, solar cells, and secondary batteries. Typical examples include trimethyl aluminum (TMA), triethyl aluminum (TEA), dimethyl zinc (DMZ), diethyl zinc (DEZ), trimethylgallium (TMG), triethyl gallium (TEG), trimethyl indium (TMI), and triethyl indium (TEI).

[0003] Although the aluminum or zinc precursors have reasonable prices and excellent performance, they are difficult to handle due to their high flammability and resulting spontaneous combustion. Therefore, there is a continuous effort to develop low-risk organometallic precursors that can achieve low flammability or non-spontaneous combustion.

[0004] However, the developed low-risk Al precursors have the following technical problems: their ligands that bind to the central metal Al are complex, they are more expensive than existing TMA precursors, and they contain residual impurities such as carbon and nitrogen in the film.

[0005] As an example, commercially available low-risk Al precursors may have the following structure.

[0006] [Examples of low-risk Al precursors]

[0007] Therefore, there is still a need to develop a technology that can stabilize highly flammable precursors, typical examples of which are trimethyl aluminum (TMA), triethyl aluminum (TEA), dimethyl zinc (DMZ), diethyl zinc (DEZ), trimethyl gallium (TMG), triethyl gallium (TEG), trimethyl indium (TMI), and triethyl indium (TEI).

[0008] Existing technical documents Patent documents Patent Document 1: Korean Patent No. 2011-0027488 Summary of the Invention The problem the invention aims to solve In order to solve the problems of the prior art as described above, the object of the present invention is to provide an azeotropic mixture in which a precursor compound with high self-ignition properties is blended with a volatility modifier in a precursor compound used to form a thin film on a substrate, so as to control the volatility of the precursor compound. Therefore, it is not only easy to inject into the chamber in a vapor state, but also to reduce the deposition rate, making it easy to accurately deposit a thin film without leaving impurities in the film.

[0009] Furthermore, the present invention aims to provide a thin film deposition method, a thin film prepared therefrom, a semiconductor substrate, and a semiconductor device, etc., which controls the volatility of the precursor compound by providing it as an azeotropic mixture. Therefore, it is not only easy to inject it into the chamber in a vapor state, but also to reduce the deposition rate, making it easy to accurately deposit thin films without leaving impurities in the film.

[0010] The objectives and other objectives of this invention can be achieved by the invention as described below.

[0011] means for solving problems To achieve the aforementioned objective, the present invention provides an azeotropic mixture comprising a precursor compound having self-ignition properties at room temperature and a volatility modifier, characterized in that... The central metal of the precursor compound is aluminum, zinc, gallium, or indium. The volatility modifier is a substance that controls the volatility of the precursor compound, and includes one or more compounds selected from cyclic compounds having three or more element species containing lone pairs of electrons and linear compounds having three or more element species containing lone pairs of electrons.

[0012] The precursor compound may be selected from one or more of trimethyl aluminum (TMA), triethyl aluminum (TEA), dimethyl zinc (DMZ), diethyl zinc (DEZ), trimethyl gallium (TMG), triethyl gallium (TEG), trimethyl indium (TMI), and triethyl indium (TEI).

[0013] The lone pair can be selected from one or more of oxygen (O), sulfur (S), phosphorus (P) and nitrogen (N).

[0014] A cyclic compound having three or more element species containing the lone pairs of electrons can be a compound represented by the following chemical formula 1.

[0015] [Chemical Formula 1]

[0016] (In the chemical formula 1, R' is hydrogen, an alkyl group having 1 to 5 carbon atoms, an olefinic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.) And A is oxygen (O), sulfur (S), phosphorus (P) or nitrogen (N). m is an integer from 0 to 2.

[0017] A linear compound having three or more elemental species containing the lone pairs of electrons can be a compound represented by the following chemical formula 2.

[0018] [Chemical Formula 2]

[0019] (In the aforementioned chemical formula 2, R” is hydrogen, an alkyl group having 1 to 5 carbon atoms, an olefinic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.) And B is -OH, -OCH3, -OCH2CH3, -CH2CH3, -SH, -SCH3 or -SCH2CH3.

[0020] The volatility modifier may include one or more compounds selected from the following chemical formulas 1-1 to 1-3 and 2-1 to 2-3. [Chemical Formulas 1-1 to 1-3] , ,

[0021] [Chemical Formulas 2-1 to 2-3] , , .

[0022] The precursor compound and the volatility modifier may be contained in a weight ratio of 1:0.5 to 5.

[0023] Under normal pressure conditions, the boiling point of the azeotropic mixture can be in the range of 40°C to 180°C.

[0024] The turbidity of the azeotropic mixture can be below 10.

[0025] The viscosity of the azeotropic mixture can be below 50 cP.

[0026] The T0 value of the azeotropic mixture can be below 200°C.

[0027] At 20°C, the vapor pressure of the azeotropic mixture can be above 0.1 Torr.

[0028] In addition, according to the present invention, a thin film deposition method is provided, characterized in that it includes the step of stacking one or more thin films by using the aforementioned azeotropic mixture.

[0029] The thin film deposition method may include: injecting an azeotropic mixture onto a substrate loaded in a chamber to adjust the auto-ignition properties of a precursor compound; removing unreacted azeotropic mixtures and byproducts by injecting an inert gas into the chamber; injecting a nitriding gas, an oxidizing gas, or a reducing gas into the chamber to form a nitriding film, an oxide film, or a metal film of a central metal of the precursor compound; and removing unreacted gases and byproducts by injecting an inert gas into the chamber.

[0030] The chamber may be an atomic layer deposition (ALD) chamber, a chemical vapor deposition (CVD) chamber, a plasma-enhanced atomic layer deposition (PEALD) chamber, or a plasma-enhanced chemical vapor deposition (PECVD) chamber.

[0031] The substrate can be heated to 100°C to 700°C.

[0032] The deposition can be carried out in the range of 100°C to 700°C.

[0033] The thin film can be formed by stacking aluminum nitride film, aluminum oxide film, aluminum metal film, zinc nitride film, zinc oxide film, zinc metal film, gallium oxide film, gallium nitride film, gallium metal film, indium oxide film, indium nitride film, and indium metal film. A typical deposited film can be indium gallium zinc oxide (InGaZnO, IGZO).

[0034] In addition, the present invention provides a thin film formed by the aforementioned thin film deposition method, characterized in that the thin film is a thin film formed by stacking a nitride film, an oxide film or a metal film of a central metal.

[0035] In the oxide film, the ratio of one or more group 13 central metals selected from Al, Ga and In to O (oxygen), as determined by AES, can be in the range of 0.6 to 0.75.

[0036] In the oxide film, the ratio of the group 12 central metal of Zn to O (oxygen), as determined by AES, can be in the range of 0.45 to 0.55.

[0037] In addition, the present invention provides a semiconductor substrate, characterized in that it includes the aforementioned thin film.

[0038] Furthermore, the present invention provides a semiconductor device characterized by comprising the aforementioned semiconductor substrate. The semiconductor device corresponds to, but is not limited to, memory (DRAM, 3D-DRAM, NAND) and logic (CPU, GPU, AP).

[0039] Invention Effects According to the present invention, it has the effect of providing an azeotropic mixture that is easy to handle by achieving low flammability or non-self-ignition, can be used directly without modifying the deposition equipment currently in use, is easy to inject into the chamber in a vapor state, reduces the deposition rate, makes it easy to accurately deposit thin films, and leaves no impurities in the film.

[0040] In addition, it has the following effects: by using the azeotropic mixture of the present invention to control the volatility of the precursor compound, it is not only easy to inject it into the chamber in a vapor state, but also to reduce the deposition rate, making it easy to accurately deposit thin films without leaving impurities in the film.

[0041] Furthermore, the azeotropic mixture of the present invention can be used as a single component and does not have a spontaneous combustion problem. When injected in sufficient or excessive amounts, gel permeation chromatography (GPC) can achieve a speed of 0.15 Å / cycle (@450). The process achieves the required 3 Å thickness at the level of C), thus enabling film growth through 20 cycles. This provides a large process margin, offering advantages such as easy thickness control and the potential for continuous film formation when creating ultrathin films. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the thin film deposition method using the azeotropic mixture of Example 1 of the present invention.

[0043] Figure 2 This is a graph showing the nuclear magnetic resonance (NMR) data of the azeotropic mixture of Preparation Example 1 of the present invention.

[0044] Figure 3 This is a graph showing the NMR data of the azeotropic mixture of Preparation Example 2 of the present invention.

[0045] Figure 4 The graph shows the results of measuring the temperature (T0) at the point where the weight loss of the azeotropic mixture and the individual volatility modifier of Preparation Example 1 of the present invention terminated.

[0046] Figure 5 The graph shows the results of impurity analysis by secondary ion mass spectrometry (SIMS) in the films formed in Example 1, Comparative Example 1, which uses the azeotropic mixture of Preparation Example 1 of the present invention alone, or Comparative Example 4, which includes the azeotropic mixture of the present invention.

[0047] Figure 6 The figure shows the roughness measurement results measured by atomic force microscopy (AFM) in the films formed in Example 1, Comparative Example 1, which uses the azeotropic mixture of Preparation Example 1 of the present invention alone, or Comparative Example 4, which includes them.

[0048] Figure 7 This is a graph showing the film composition ratios determined by AES in films formed in Example 2, Comparative Example 1, which uses the azeotropic mixture of Preparation Example 2 of the present invention alone, or Comparative Example 4, which includes them.

[0049] Figure 8 It is the aforementioned Figure 7 A schematic diagram illustrating why the Al / O ratio measured by AES exceeds 0.671 (close to the stoichiometric value) and the higher the value, the lower the electrical properties. Detailed Implementation

[0050] The azeotropic mixtures, thin film deposition methods using them, and semiconductor substrates prepared therefrom in this invention will be described in detail below.

[0051] In this invention, "azeotropic mixture" refers to a novel composition in which a volatility modifier is incorporated into the precursor compound used in the deposition reaction instead of a reducing agent, thereby stabilizing the volatility of the precursor compound and simultaneously allowing both the precursor compound and the volatility modifier to volatilize without increasing the boiling point of the precursor, and providing a synergistic effect of reducing / controlling the deposition rate.

[0052] In this invention, unless otherwise stated, “modification” means to improve the film quality of the thin film (such as reducing resistivity, increasing density and reducing impurities) without adversely affecting the adsorption of the central metal of the precursor compound onto the substrate and having a positive effect on the formation of the metal film.

[0053] In this invention, unless otherwise mentioned, % refers to weight.

[0054] The inventors have confirmed that, in the course of continuing research on technologies capable of stabilizing highly flammable precursors (typical examples being trimethylaluminum (TMA), triethylaluminum (TEA), dimethyl zinc (DMZ), diethyl zinc (DEZ), trimethyl gallium (TMG), triethylgallium (TEG), trimethyl indium (TMI), and triethyl indium (TEI)), when the specified compound is mixed with the precursor compound, it is easy to handle by achieving low flammability or non-self-ignition, exhibiting not only simultaneous volatility but also the ability to reduce / control the deposition rate of thin films, and through related research, this invention was completed.

[0055] According to the present invention, an azeotropic mixture comprising a precursor compound having self-ignition properties at room temperature and a volatility modifier can be provided, which has the following advantages: it is easy to handle by achieving low flammability or non-self-ignition, and not only exhibits simultaneous volatility, but also has the ability to reduce / control the deposition rate of thin films.

[0056] The precursor compound that is spontaneously combustible under normal temperature conditions can be a known highly flammable precursor compound.

[0057] As an example, the central metal of the precursor compound may be aluminum, zinc, gallium, or indium.

[0058] The precursor compound may be selected from one or more of trimethyl aluminum (TMA), triethyl aluminum (TEA), dimethyl zinc (DMZ), diethyl zinc (DEZ), trimethyl gallium (TMG), triethyl gallium (TEG), trimethyl indium (TMI), and triethyl indium (TEI).

[0059] As an example, the physical properties of the precursor compound are shown in Table 1 below.

[0060] Table 1

[0061] *General formula: M (family 12)-L2, M (family 13)-L3, L is -CH3, -CH2CH3, -CH2CH2CH3, -iPr.

[0062] The precursor compound may be included in the overall composition of the azeotropic mixture in the range of 1 wt% to 99 wt%, 10 wt% to 90 wt%, or 30 wt% to 70 wt%, and is sufficient to exert the aforementioned synergistic effect.

[0063] The volatility modifier is characterized in that it comprises one or more compounds selected from cyclic compounds having three or more element species containing lone pairs of electrons and linear compounds having three or more element species containing lone pairs of electrons. In this case, not only can the volatility of the precursor compound be appropriately controlled, but also low flammability or non-self-ignition can be achieved, and it has the advantage of providing storage stability under normal temperature conditions.

[0064] The lone pair can be selected from one or more of oxygen (O), sulfur (S), phosphorus (P) and nitrogen (N).

[0065] The volatility modifier may contain linear or cyclic saturated hydrocarbons or linear saturated hydrocarbons having three or more nitrogen (N), oxygen (O), phosphorus (P) or sulfur (S) and having 3 to 15 carbon atoms. In this case, it has the following effects: it is easy to handle by achieving low flammability or non-self-ignition, and it can not only exhibit simultaneous volatility, but also achieve the ability to reduce / control the deposition rate of thin films.

[0066] As a specific example, a cyclic compound having three or more element species containing the aforementioned lone pairs of electrons can be a compound represented by the following chemical formula 1. In this case, not only can the volatility of the precursor compound be appropriately controlled, but low flammability or non-self-ignition can also be achieved, and it has the advantage of providing storage stability at room temperature.

[0067] [Chemical Formula 1]

[0068] (In the chemical formula 1, R' is hydrogen, an alkyl group having 1 to 5 carbon atoms, an olefinic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.) The A is oxygen (O), sulfur (S), phosphorus (P), or nitrogen (N). m is an integer from 0 to 2.

[0069] Linear compounds having three or more element species containing the aforementioned lone pairs of electrons can be compounds represented by the following chemical formula 2. In this case, not only can the volatility of the precursor compound be appropriately controlled, but low flammability or non-self-ignition can also be achieved, and it has the advantage of providing storage stability at room temperature.

[0070] [Chemical Formula 2]

[0071] (In the aforementioned chemical formula 2, R” is hydrogen, an alkyl group having 1 to 5 carbon atoms, an olefinic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.) The B is -OH, -OCH3, -OCH2CH3, -CH2CH3, -SH, -SCH3, or -SCH2CH3.

[0072] The volatility modifier may include one or more compounds selected from those represented by chemical formulas 1-1 to 1-3 and 2-1 to 2-3. In this case, not only can the volatility of the precursor compound be appropriately controlled, but also low flammability or non-self-ignition can be achieved, and it has the advantage of providing storage stability at room temperature.

[0073] [Chemical Formulas 1-1 to 1-3] , ,

[0074] [Chemical Formulas 2-1 to 2-3] , , .

[0075] Preferably, the volatility modifier can be a compound with a purity of 99.9% or higher, a purity of 99.95% or higher, or a purity of 99.99% or higher. For reference, if a compound with a purity of less than 99% is used, impurities may remain in the film or react with precursors or reactant gases. Therefore, materials with a purity of 99% or higher should be used whenever possible.

[0076] The volatility modifier may be included in the overall composition of the azeotropic mixture in the range of 1% to 99% by weight, 10% to 90% by weight, or 30% to 70% by weight, and is sufficient to exert the aforementioned synergistic effect.

[0077] As an example, the precursor compound and the volatility modifier may be contained in a molar ratio of 1:0.5 to 5, and as a specific example, they may be contained in a molar ratio of 1:1 to 3.

[0078] Under normal pressure conditions, the boiling point of the azeotropic mixture can be in the range of 40°C to 180°C.

[0079] The azeotropic mixture may be a lemon-colored or colored substance.

[0080] The turbidity of the azeotropic mixture can be below 10.

[0081] The turbidity was measured using a portable turbidimeter. As the turbidity decreased to below 10, transparent physical properties were achieved in the deposited film. Suspensions can form when the precursor compound reacts with the mixed volatile modifiers to produce precipitates. During material transfer, these can clog narrow lines or LDS capillaries, leading to particulate contamination of the spray head and chambers, ultimately resulting in particulate contamination on the semiconductor substrate, which can be a fatal defect in the device. Therefore, it is important to measure the turbidity and confirm the absence of precipitates after thoroughly stirring the azeotropic mixture.

[0082] The viscosity of the azeotropic mixture can be below 50 cP.

[0083] The viscosity was measured using a vibratory viscometer. Performance improved as the viscosity decreased to below 50 cP, which also helped reduce / control the deposition rate. At high viscosities, the transport of the azeotropic mixture was limited due to fluid resistance when passing through narrow pipelines or LDS capillaries.

[0084] The T0 value of the azeotropic mixture can be below 200°C. Figure 4 This is a graph showing the results of measuring the temperature (T0) at which the weight loss of the azeotropic mixture and the individual volatility modifier of Preparation Example 1 of the present invention terminated. As follows... Figure 4As shown, the volatility modifier 1 (please specify the component name) has a T0 value of 55.3 degrees, while the azeotropic mixture of the present invention has a T0 value of 123.8 degrees, which satisfies the boiling point formation suitable for vaporization, uniformly diffuses onto the substrate, and can reduce / control the deposition rate.

[0085] One example of the thin film deposition method of the present invention may include the step of stacking one or more thin films by using the aforementioned azeotropic mixture.

[0086] As an example, the thin film deposition method reflects the following Figure 1 The process diagram shown illustrates a method characterized by comprising: a first step of injecting a self-ignition-modified azeotropic mixture onto a substrate loaded in a chamber to allow the azeotropic mixture (precursor) to adhere; a second step of removing excess azeotropic mixture and byproducts by injecting an inert gas into the chamber; a third step of injecting a nitriding gas, an oxidizing gas, or a reducing gas into the chamber to form a nitriding film, an oxide film, or a metal film from the central metal in the precursor compound; and a fourth step of removing unreacted gas and byproducts by injecting an inert gas into the chamber. This method offers the following advantages: it allows for direct use and control of the volatility of the precursor compound without modifying existing deposition equipment; it facilitates injection into the chamber in vapor form; it reduces the deposition rate; it facilitates precise deposition of thin films; and it effectively provides films free of impurities.

[0087] Depending on the circumstances, multi-component alloys can be fabricated into thin films. An indium oxide molecular layer is formed by using a first azeotropic mixture (e.g., an indium azeotropic mixture precursor) in the first step, followed by a purging process in the second step, the injection of a reactant (e.g., ozone) in the third step, and a purging process in the fourth step. Next, a gallium oxide molecular layer is formed by using a second azeotropic mixture (e.g., a gallium azeotropic mixture precursor) in the first step, followed by a purging process in the second step, the injection of a reactant (e.g., ozone) in the third step, and a purging process in the fourth step. Similarly, a zinc oxide molecular layer is formed by using a third azeotropic mixture (e.g., a zinc azeotropic mixture precursor) in the first step, followed by a purging process in the second step, the injection of a reactant (e.g., ozone) in the third step, and a purging process in the fourth step. This process can be repeated sequentially to form an IGZO thin film. When the first to fourth steps of the first azeotropic mixture are performed x times, the first to fourth steps of the second azeotropic mixture are performed y times, and the first to fourth steps of the third azeotropic mixture are performed z times, the composition ratio of the alloy layer can be adjusted by making the respective execution ratios the same or different. When the execution ratios are different, the following supercycle ratios are followed: when x is 10 times, y or z can be 1 to 9 times; when y is 10 times, x or z can be 1 to 9 times; when z is 10 times, x or y can be 1 to 9 times.

[0088] The first step can be carried out under inactive gas conditions, which can reduce the formation of byproducts and improve the deposition rate.

[0089] The inactive gas can be nitrogen, helium, or argon, and should have a purity of 4N to 9N as much as possible to maximize its effectiveness.

[0090] The first to fourth steps described above can be repeated in unit cycles until a metal film of the desired thickness is obtained. In this case, the following advantages are available: the generated byproducts are effectively removed to reduce the resistivity, the step coverage is significantly improved and the uniformity is improved, while the film quality (electrical properties and density, etc.) is improved, and a low-resistivity deposited film is provided.

[0091] The chamber can be an ALD chamber, a CVD chamber, a PEALD chamber, or a PECVD chamber.

[0092] The substrate loaded in the chamber can be heated to 100°C to 700°C.

[0093] In the first step, preferably, the azeotropic mixture can be transferred into the chamber via VFC, DLI or LDS, more preferably via LDS.

[0094] As an example, the substrate loaded in the chamber can be heated to 100°C to 700°C, specifically to 300°C to 600°C. The azeotropic mixture can be injected onto the substrate in a heated or unheated state, and depending on the deposition efficiency, it can also be injected in an unheated state, with the heating conditions adjusted during the deposition process. As an example, it can be injected onto the substrate for 1 to 20 seconds at a temperature of 50°C to 400°C.

[0095] Preferably, the process may include the following steps: preheating the temperature inside the chamber to the deposition temperature before introducing the azeotropic mixture into the chamber; and / or purging the chamber by injecting an inactive gas before introducing the azeotropic mixture into the chamber.

[0096] The process may include a step of vaporizing the azeotropic mixture and injecting it into a plasma post-treatment process, which can improve the film growth rate and reduce byproducts.

[0097] In the second step, the amount of inert gas introduced into the chamber is not particularly limited, as long as it is sufficient to remove the unreacted azeotropic mixture. However, as an example, based on the volume of the azeotropic mixture introduced into the chamber, it can be 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times. Within this range, the unreacted azeotropic mixture can be sufficiently removed to ensure uniform film formation and prevent film quality deterioration. The amounts of inert gas and azeotropic mixture introduced are based on one cycle, and the volume of the azeotropic mixture refers to the volume of the azeotropic mixture vapor.

[0098] In the third step, a reaction gas is supplied. The reaction gas is not particularly limited as long as it is a reaction gas commonly used in the technical field to which this invention pertains; preferably, it may contain a nitriding gas, an oxidizing gas, or a reducing gas. The reaction gas reacts with the central metal of the precursor compound adsorbed on the substrate to form a nitriding film, an oxide film, or a metal film.

[0099] Preferably, the oxidizing gas is O2, O3, N2O, NO2, H2O, or O2 plasma.

[0100] The nitriding gas is N2, N2H2, NH3, or a plasma thereof.

[0101] The reducing gas is H2 or its plasma.

[0102] In the step of injecting the reactive gas onto the substrate surface, the feeding time (in seconds) for each cycle of supplying the reactive gas to the substrate surface is preferably 0.01 seconds to 10 seconds, more preferably 0.02 seconds to 8 seconds, even more preferably 0.04 seconds to 6 seconds, and most preferably 0.05 seconds to 4 seconds. Within this range, it has the advantages of low film growth rate, excellent step coverage, and good economy.

[0103] In this invention, the feeding time of the reaction gas is based on a flow rate of 0.1 mg / cycle to 8000 mg / cycle in a chamber volume of 15L to 20L, and more specifically, in a chamber volume of 18L, it is based on a flow rate of 10 mg / cycle to 5000 mg / cycle.

[0104] Then, as the fourth step, purging is performed using an inactive gas.

[0105] The purging rate is preferably from 1000 sccm (Standard Cubic Centimeter per Minute) to 50000 sccm, more preferably from 2000 sccm to 30000 sccm, and even more preferably from 2500 sccm to 15000 sccm. Within this range, the membrane growth rate per cycle is appropriately controlled, and deposition is achieved in the form of an atomic mono-layer or a molecular layer, or in a manner similar to that thereof, thus providing advantages in terms of membrane quality.

[0106] As an example, the thin film deposition method can be carried out at a deposition temperature in the range of 100°C to 700°C, preferably in the range of 200°C to 500°C. In this case, as an example, a thin film with a thickness of 0.05 (=0.5 Å) to 20 nm, preferably 0.07 nm to 15 nm, more preferably 0.1 nm to 13 nm, and even more preferably 1.2 nm to 10 nm is formed at a reduced deposition rate, thereby enabling precise deposition.

[0107] As an example, the thin film deposition method can be carried out at a deposition pressure in the range of 0.01 Torr to 20 Torr, preferably in the range of 0.1 Torr to 20 Torr, more preferably in the range of 0.1 Torr to 10 Torr, and most preferably in the range of 0.3 Torr to 7 Torr, within which a metal film of uniform thickness is obtained.

[0108] In this invention, the deposition temperature and deposition pressure can be measured as the temperature and pressure formed in the deposition chamber, or as the temperature and pressure applied to the substrate in the deposition chamber.

[0109] To form a metal film of the required thickness, the unit cycle can be repeated.

[0110] As an example, the unit cycle can be repeated from 1 to 99,999 times, preferably from 10 to 1,000 times, more preferably from 50 to 5,000 times, and even more preferably from 100 to 2,000 times. Within this range, it exhibits the desired membrane properties very well.

[0111] As another example, the thin film deposition method reflects the following Figure 2 The process diagram shown illustrates a method characterized by comprising: a second-1 step of injecting a precursor compound and an azeotropic mixture onto a substrate loaded in a chamber, reducing the precursor compound while converting it into a second gas to form a deposition film of a central metal constituting the precursor compound; and a second-2 step of removing unreacted precursor compounds, unreacted second gas, and byproducts by injecting an inactive gas into the chamber. In this case, it offers the advantage of providing a thin film deposition method and a semiconductor substrate thus prepared. The method reduces process steps and impurities, improves resistivity, and enhances deposition characteristics, thereby achieving uniform thickness even when forming a metal film on a substrate with a complex structure, and providing a metal film with improved resistance.

[0112] Step 2-1 can be carried out under inactive gas conditions, which can reduce the generation of byproducts and improve the deposition rate.

[0113] The inactive gas can be nitrogen, helium, or argon, and should have a purity of 4N to 9N as much as possible to maximize its effectiveness.

[0114] Steps 2-1 to 2-2 described above can be repeated in unit cycles until a metal film of the desired thickness is obtained. In this way, when the azeotropic mixture and the precursor compound are added simultaneously in one cycle to improve the film quality, the following advantages are available: the generated byproducts are effectively removed to reduce the resistivity, the step coverage is significantly improved and the uniformity is improved, while the film quality (electrical properties and density, etc.) is improved, and a low-resistivity deposited film is provided.

[0115] The chamber can be an ALD chamber, a CVD chamber, a PEALD chamber, or a PECVD chamber.

[0116] The substrate loaded in the chamber can be heated to 100°C to 700°C.

[0117] In step 2-1, preferably, the precursor compound and the film-modified composition are transferred into the chamber via VFC, DLI, or LDS, and more preferably, via VFC.

[0118] As an example, the substrate loaded in the chamber can be heated to 100°C to 700°C, specifically to 300°C to 600°C. The precursor compound or the azeotropic mixture can be injected onto the substrate in either a heated or unheated state. Depending on the deposition efficiency, it can also be injected in an unheated state, with the heating conditions adjusted during the deposition process. For example, at a temperature of 50°C to 400°C, it can be injected onto the substrate for 1 to 20 seconds.

[0119] Preferably, the process may include the following steps: heating the chamber temperature to the deposition temperature before introducing the precursor compound and the film-modified composition into the chamber; and / or purging the chamber by injecting an inactive gas before introducing the precursor compound and the film-modified composition into the chamber.

[0120] The process may include a step of vaporizing and injecting the precursor compound followed by plasma post-treatment, which can improve membrane growth rate and reduce byproducts.

[0121] In the step of injecting the azeotropic mixture onto the substrate surface, the feeding time (in seconds) of supplying the azeotropic mixture to the substrate surface in each cycle is preferably 0.01 seconds to 10 seconds, more preferably 0.02 seconds to 8 seconds, even more preferably 0.04 seconds to 6 seconds, and most preferably 0.05 seconds to 4 seconds. Within this range, it has the advantages of low film growth rate, excellent step coverage, and good economy.

[0122] In this invention, the feeding time of the azeotropic mixture is based on a flow rate of 0.1 mg / cycle to 8000 mg / cycle in a chamber volume of 15L to 20L, and more specifically, on a chamber volume of 18L, at a flow rate of 10 mg / cycle to 5000 mg / cycle.

[0123] In step 2-2, the amount of inactive gas introduced into the chamber is not particularly limited, as long as it is sufficient to remove the unreacted gas and byproducts. However, as an example, based on the volume of the precursor compound introduced into the chamber, it can be 10 to 10,000 times, preferably 50 to 50,000 times, and more preferably 100 to 10,000 times. Within this range, unreacted gas and byproducts can be sufficiently removed to ensure uniform film formation and prevent film quality deterioration. The amounts of inactive gas and precursor compound introduced are based on one cycle, and the volume of the precursor compound refers to the volume of the precursor compound vapor.

[0124] In this invention, the disclosed purging rate is preferably from 1000 sccm (Standard Cubic Centimeters per Minute) to 50000 sccm, more preferably from 2000 sccm to 30000 sccm, and even more preferably from 2500 sccm to 15000 sccm. Within this range, the membrane growth rate per cycle is appropriately controlled, and deposition is achieved in the form of an atomic mono-layer or a molecular layer or in a manner similar to that thereof, thereby providing advantages in terms of membrane quality.

[0125] As an example, the thin film deposition method can be carried out at a deposition temperature in the range of 100°C to 700°C, preferably in the range of 300°C to 500°C, and more preferably in the range of 300°C to 400°C. Within this range, as mentioned above, even under lower process temperature conditions, the deposition characteristics, electrical properties, and film quality of the deposited metal film without impurities can be improved by the strong effect of conversion into a second gas.

[0126] As an example, the thin film deposition method can be carried out at a deposition pressure in the range of 0.01 Torr to 20 Torr, preferably in the range of 0.1 Torr to 20 Torr, more preferably in the range of 0.1 Torr to 10 Torr, and most preferably in the range of 0.3 Torr to 7 Torr, within which a metal film of uniform thickness is obtained.

[0127] In this invention, the deposition temperature and deposition pressure can be measured as the temperature and pressure formed in the deposition chamber, or as the temperature and pressure applied to the substrate in the deposition chamber.

[0128] To form a metal film of the required thickness, the unit cycle can be repeated.

[0129] As an example, the unit cycle can be repeated from 1 to 99,999 times, preferably from 10 to 1,000 times, more preferably from 50 to 5,000 times, and even more preferably from 100 to 2,000 times. Within this range, it exhibits the desired membrane properties very well.

[0130] The thin film deposition method is based on a metal film thickness of 100 angstroms as determined by SIMS. Preferably, the intensity (c / s) of residual impurities (carbon or halogen elements) in the metal film can be less than 100,000, more preferably less than 70,000, even more preferably less than 50,000, most preferably less than 10,000, and as a preferred embodiment, less than 5,000, more preferably 10 to 4,000, and even more preferably 10 to 3,000. Within this range, the effect of preventing crystallinity and electrical property degradation is excellent.

[0131] The thin film obtained by the thin film deposition method of the present invention can be formed by stacking one or more metal films, nitride films or oxide films selected from group 12 metals Zn and group 13 metals Al, Ga, In.

[0132] In addition, the present invention provides a thin film formed by the aforementioned thin film deposition method, characterized in that the thin film is a thin film formed by stacking a nitride film, an oxide film or a metal film of a central metal.

[0133] In the oxide film, the ratio of one or more group 13 central metals selected from Al, Ga and In to O (oxygen), as determined by AES, can be in the range of 0.6 to 0.75.

[0134] Furthermore, in the oxide film, the ratio of the group 12 central metal of Zn to O (oxygen), as determined by AES, can be in the range of 0.45 to 0.55.

[0135] As an example, regarding Al x O y Specifically, it is suitable for the ideal AES determination of the Al / O ratio of 0.671 in chemometrics. Beyond this value, as will be discussed later... Figures 7 to 8 As shown, carbon or hydrogen impurities may remain in the thin film. In this case, the electrical properties may be degraded, resulting in a decrease in dielectric constant (k) and breakdown field (MV / cm).

[0136] As a specific example, in the oxide film, the ratio of one or more group 13 central metals selected from Al, Ga and In to O (oxygen), as determined by AES, can be in the range of 0.6 to 0.75.

[0137] Furthermore, in the oxide film, the ratio of the group 12 central metal of Zn to O (oxygen), as determined by AES, can be in the range of 0.45 to 0.55.

[0138] The thin film may be an aluminum nitride film, an aluminum oxide film, a metallic aluminum film, a zinc nitride film, a zinc oxide film, or a metallic zinc film, a gallium oxide film, a gallium nitride film, a metallic gallium film, an indium oxide film, an indium nitride film, or a metallic indium film, etc.

[0139] The thin film can be used in a variety of ways as a material for commonly used semiconductors, displays, solar cells, and secondary batteries.

[0140] As an example, the thin film can be used in semiconductor devices as a wiring metal film or for low-resistance applications.

[0141] The resistivity of the thin film can be in the range of 5 μΩ·cm to 1000 μΩ·cm.

[0142] As an example, the film may contain less than 100 ppm of halogen compounds. For reference, regarding excessive halogen residue, as an example, when using the nitriding agent described later at temperatures of 200°C to 300°C, chlorides (such as NH4Cl) are generated and remain in the metal film, which is therefore not preferred.

[0143] In particular, when forming relatively sparse films, the film growth rate is significantly reduced, thus ensuring uniformity even for substrates with complex structures. It can be deposited to a particularly thin thickness and can reduce the amount of O, Si, metals, metal oxides, and even carbon residues that are currently difficult to reduce, which are left as byproducts.

[0144] Furthermore, in this invention, the apparatus for preparing the thin film deposition method may include: a chamber; a vaporizer for generating a precursor compound by vaporizing an azeotropic mixture; a first moving unit for transferring the vaporized azeotropic mixture into the chamber; and a second moving unit for transferring the reaction gas into the chamber. The vaporizer and moving unit are not particularly limited as long as they are commonly used in the technical field to which this invention pertains.

[0145] As a specific example, when describing the thin film deposition method, firstly, a substrate with a thin film formed on its upper part is placed in a chamber where deposition can be performed.

[0146] The substrate may include a semiconductor substrate, such as a silicon substrate and silicon oxide.

[0147] A conductive layer or an insulating layer may also be formed on the upper part of the substrate.

[0148] In order to deposit a thin film on the substrate located in the deposition chamber, the above-mentioned azeotropic mixture (a mixture of precursor compound and volatile modifier) ​​is prepared respectively.

[0149] Then, the prepared azeotropic mixture is injected into the vaporizer, where it is converted into a vapor phase, and then... Figure 1 The process shown involves transferring the material to the deposition chamber and injecting it into the chamber to purge unreacted material or byproducts.

[0150] Next, the reactive gas is injected into the chamber, and a nitride film, oxide film or metal film is formed on the substrate. Then, the unreacted reactive gas or byproducts are purged.

[0151] The deposition rate of the film can be from 0.05 Å / cycle to 0.3 Å / cycle, within which accurate and thin films can be effectively provided.

[0152] The present invention also provides a semiconductor substrate, characterized in that it is prepared by the thin film deposition method of the present invention, in which the substrate has excellent uniformity of film thickness and excellent density and electrical properties.

[0153] Preferably, the thickness of the film is less than 30 nm, with a film thickness of 10 nm as a reference, the resistivity is from 5 μΩ·cm to 2000 μΩ·cm, the impurity content is less than 10000 ppm, and the step coverage is more than 90%. Within this range, it has excellent performance as a diffusion prevention film and excellent effect as a metal wiring material, but is not limited thereto.

[0154] As an example, the thickness of the film can be from 0.05 (=0.5 Å) to 20 nm, preferably from 0.07 nm to 15 nm, more preferably from 0.1 nm to 13 nm, and even more preferably from 1.2 nm to 10 nm. Within this range, the film exhibits excellent film properties.

[0155] As an example, based on a film thickness of 10 nm, the resistivity of the film can be from 0.1 μΩ·cm to 400 μΩ·cm, preferably from 0.1 μΩ·cm to 200 μΩ·cm, and more preferably from 0.1 μΩ·cm to 20 μΩ·cm. Within this range, the film exhibits excellent film properties.

[0156] The impurity content of the thin film can be below 10,000 ppm or from 1 ppm to 9,000 ppm, more preferably from 1 ppm to 8,500 ppm, and even more preferably from 1 ppm to 1,000 ppm. Within this range, it exhibits excellent film crystallinity and improves resistivity. The impurities remaining in the thin film are those resulting from incomplete reduction of the metal precursor ligand. For example, these can be carbon, nitrogen, oxygen, or halogen elements. The lower the residual impurity content in the thin film, the better the film quality.

[0157] The film is characterized in that, when the impurity content of the ligand-derived film is determined by XPS, the impurities (such as carbon) are reduced to below 1%.

[0158] In this invention, unless otherwise mentioned, % refers to weight.

[0159] As an example, the thin film has a step coverage of 90% or more, preferably 92% or more, more preferably 95% or more. Within this range, even complex structures can be easily deposited on the substrate, thus having the advantage of being suitable for next-generation semiconductor devices.

[0160] The thickness of the prepared thin film is preferably below 20 nm, based on a metal film thickness of 10 nm, the impurity content (carbon, nitrogen, oxygen and halogen, etc.) is below 10,000 ppm, and the step coverage is above 90%. Within this range, it has excellent performance as a metal wiring or semiconductor device, but is not limited thereto.

[0161] The metal film is characterized by improved crystallinity as determined by XRD.

[0162] Hereinafter, preferred embodiments and accompanying drawings are presented to facilitate understanding of the present invention. However, the following embodiments and accompanying drawings are only used to illustrate the present invention. It will be obvious to those skilled in the art that various changes and modifications can be made within the scope and technical concept of the present invention, and such changes and modifications are naturally within the scope of the appended claims.

[0163] [Example] Preparation Example 1 Trimethyl aluminum (TMA) was prepared as a precursor compound, and dimethyl carbonate (DMC) was prepared as a volatility modifier 1, in order to prepare a mixture thereof.

[0164] An azeotropic mixture was prepared by blending the precursor compound and volatility modifier 1 at a weight ratio of 1:2.

[0165] The NMR results of the azeotropic mixture are shown below. Figure 2 .

[0166] the following Figure 2 This is a graph showing the NMR data of the azeotropic mixture of Preparation Example 1 of the present invention.

[0167] As follows Figure 2 As shown, the peak shift resulted in a decrease in the peak width between the precursor compound and the volatility modifier 1, thus confirming the formation of a stable adduct.

[0168] Preparation Example 2 Trimethyl aluminum (TMA) was prepared as a precursor compound, and diethyl carbonate (DEC) was prepared as a volatility modifier 1, to prepare a mixture thereof.

[0169] An azeotropic mixture was prepared by blending the precursor compound and the volatility modifier 2 in a weight ratio of 1:2.

[0170] The NMR results of the azeotropic mixture are shown below. Figure 3 .

[0171] the following Figure 3 This is a graph showing the NMR data of the azeotropic mixture of Preparation Example 2 of the present invention.

[0172] As follows Figure 3 As shown, the peak shift resulted in a decrease in the peak width between the precursor compound and the volatility modifier 1, thus confirming the formation of a stable adduct.

[0173] [Experimental Example] The boiling points of the azeotropic mixtures obtained in Preparation Examples 1 to 2 were determined, and simultaneous volatilization was confirmed. The results are shown in Table 2 below.

[0174] Furthermore, the azeotropic mixtures and volatile modifiers 1 and 2 obtained in Preparation Examples 1 to 2 were subjected to APHA color value determination, turbidity determination, viscosity determination, and T0 value determination in the following manner.

[0175] *Turbidity Measurement: The azeotropic mixtures and volatile modifiers 1 and 2 obtained in Preparation Examples 1 to 2 were measured using a portable turbidimeter. The turbidimeter was used to measure the turbidity of the mixtures in bottles placed in a glove box under inert gas conditions. The results are shown in Table 2 below.

[0176] *Viscosity Measurement: The azeotropic mixtures and volatile modifiers 1 and 2 obtained in Preparation Examples 1 to 2 were measured using a vibratory viscometer in a glove box under inert gas conditions. The results are shown in Table 2 below.

[0177] *T0 value determination: The azeotropic mixtures and volatile modifiers 1 and 2 obtained in Preparation Examples 1 to 2 were determined using a thermogravimetric analysis (TGA) with a ramp rate of 5ºC / min. The results are shown in Table 2 below. Figure 4 .

[0178] The results of the measured boiling point, turbidity, viscosity, and T0 value are summarized in Table 2 below.

[0179] Table 2

[0180] As shown in Table 2 and Figure 4 As shown, the azeotropic mixture of the present invention can not only volatilize simultaneously, but also lower the boiling point, and its high purity can be confirmed from the APHA color value and turbidity. It can be confirmed that it not only has a viscosity suitable for processing, but also satisfies the boiling point formation suitable for vaporization at the temperature (T0) at the end of weight loss, so as to satisfy the temperature below 180 degrees as a reference for uniform diffusion onto the substrate and the ability to reduce / control the deposition rate.

[0181] For reference, the following Figure 4 The graph shows the results of measuring the temperature (T0) at the point where the weight loss of the azeotropic mixture and the individual volatility modifier of Preparation Example 1 of the present invention terminated.

[0182] Examples 1 to 3, Comparative Examples 1 to 6 Use the following Figure 1 The deposition process was performed using the process described in Preparation Example 1. O2 gas was used as the reactant gas, and the following is for reference: Figure 1 This is a schematic diagram illustrating a thin film deposition method using the azeotropic mixture of Example 1 of the present invention.

[0183] The specific process sequence and the materials and their contents used in each process are shown in Table 2 below.

[0184] For reference, the TMA injection rate in Comparative Examples 1 to 6 was 0.01 g / cycle (in a 10 L ALD chamber), and the modifier injection rate in Comparative Examples 4 to 6 was 0.01 g / cycle (in a 10 L ALD chamber). The azeotropic mixture in Examples 1 to 3 was an azeotropic mixture composed of TMA (trimethylaluminum) and volatile modifier 1 (TMA:volatile modifier 1 = 1:2 equivalent ratio), and was injected into a 10 L ALD chamber at a rate of 0.015 g / cycle.

[0185] [Experimental Example] For each of the thin films obtained in Examples 1 to 3 and Comparative Examples 1 to 6, the impurity content, the types and contents of elements constituting the surface of the material, the deposition rate, the crystal structure and orientation, etc., were confirmed by the following methods.

[0186] *Secondary-ion mass spectrometry (SIMS) C impurities: When the sputtering time is 50 seconds, which allows the ion sputterer to penetrate the thin film axially and cause minimal contamination on the substrate skin, the C impurity content (counts) is considered and the C impurity value is confirmed in the SIMS curve.

[0187] *Atomic emission spectroscopy (AES) Al / O ratio: Auger electron spectroscopy uses an ion sputtering instrument to penetrate the thin film along the axial direction and analyze the composition of the thin film at depth. During packaging and processing, the top layer of the substrate may be contaminated by fingerprints, etc. Therefore, the sputtering time is reduced to 0.6 minutes until the top layer is removed. At this depth, a red scale line is used as a guideline for the thin film composition. The ratio of aluminum (Al) to oxygen (O) is calculated, and the Al content is... x O y The composition of the thin film is shown below Figure 7 middle.

[0188] *Atomic force microscopy (AFM) roughness (Rq): Using an atomic force microscope, the 5×5μm area of ​​the thin film is scanned in a non-contact manner. 2 The area was surveyed, and the roughness value was measured.

[0189] * Deposition Rate (GPC) Measurement: The deposition rate (GPC) of each film obtained in Examples 1 to 3 and Comparative Examples 1 to 6 was measured in the following manner. Specifically, the thickness of the film with a thickness range of 3 nm to 30 nm was measured using an ellipsometry, and the deposition rate was calculated by dividing by the number of depositions, with the unit being Å / cycle.

[0190] Table 3

[0191] In Table 3, the abbreviation S refers to the precursor compound, the abbreviation P refers to purging, the abbreviation R refers to the oxidizing gas, the abbreviation A refers to the volatile modifier, and O3 refers to ozone.

[0192] In Table 3, as follows Figures 5 to 6 As shown, according to Example 1 and others, which used the azeotropic mixture of the present invention, compared with Comparative Example 1 (where the volatile modifier was removed from the azeotropic mixture), it can be confirmed that the deposition rate reduction capability, electrical properties, film quality, surface properties and impurity reduction characteristics are all effectively improved.

[0193] Additionally, as described in Table 3 and below Figures 5 to 6 As shown, according to Example 1 and others, which used the azeotropic mixture of the present invention, compared with Comparative Example 4 (which was prepared with TMA and volatility modifier 1 respectively, instead of the azeotropic mixture), it can be confirmed that the deposition rate reduction capability, electrical properties, film quality, surface properties and impurity reduction characteristics are all effectively improved.

[0194] For reference, in a typical ZAZ (ZrO2 / Al2O3 / ZrO2) multilayer film process used in DRAM dielectric film manufacturing, the Al2O3 layer between the ZrO2 particles is very thin. If the Al2O3 layer is too thin, the energy storage capacity will be reduced; if it is too thick, there will be problems with poor electrical properties.

[0195] In the conventional TMA+O3 process, the injection rate is 0.5 Å / cycle. When the precursor injection rate is drastically reduced, it can be reduced to 0.3 Å / cycle. However, there is a trade-off: it is difficult to ensure that the required and sufficient amount of injected vapor is delivered to the lower part of the patterned orifice.

[0196] Therefore, it takes up to 10 cycles of process to deposit an Al2O3 film with a thickness of 0.5 nm (=5 Å).

[0197] When deposited at a thinner 0.3 nm (=3 Å), the cycling rate is significantly reduced, making it difficult to control in mass production processes.

[0198] Conversely, according to the present invention, when an azeotropic mixture that can be used as a single component and does not pose a self-ignition problem is injected in sufficient or excess quantity, GPC can provide 0.15 Å / cycle (@450). The process margin is such that, at the level of C), the film can be grown by performing 20 cycles at the required 3 Å for deposition. This provides a large process margin, offering the advantages of easy thickness control and facilitating the formation of continuous films when forming ultrathin films.

[0199] Furthermore, Al was determined by AES measurement. x O y The composition of the thin film is shown below. Figure 7 . the following Figure 7 This is a graph showing the film composition ratios determined by AES in films formed in Example 2, Comparative Example 1, which uses the azeotropic mixture of Preparation Example 2 of the present invention alone, or Comparative Example 4, which includes them.

[0200] As follows Figure 7 As shown, Al was determined by AES measurement. x O y Composition of the film. For Comparative Example 1 (removal of the volatile modifier from the azeotropic mixture) and Comparative Example 4 (preparation of TMA and volatile modifier 1, respectively, instead of an azeotropic mixture), the compositions with Al / O ratios of 0.813 and 0.788 were confirmed as Al2O. 2.45 and Al2O 2.53 None of them reached the stoichiometric value of Al2O3.

[0201] Conversely, according to Example 2 using the azeotropic mixture of the present invention, the Al / O ratio was confirmed to be 0.671, which is Al2O. 2.98 As an ideal level thin film close to stoichiometry, it conforms to Al2O3.

[0202] On the other hand, when the Al / O ratio exceeds 0.671 (close to the stoichiometric value) and its value is large, as follows: Figure 8 The schematic diagram shows that carbon or hydrogen impurities may remain in the thin film. In this case, the electrical properties may be degraded, resulting in a decrease in dielectric constant (k) and breakdown field (MV / cm).

[0203] Ultimately, it was confirmed that in the precursor compounds used to form thin films on the substrate, a precursor compound with high self-ignition properties is blended with a volatility modifier to control the volatility of the precursor compound. Therefore, it is not only easy to inject into the chamber in vapor form, but also to effectively reduce the deposition rate, enabling the precise stacking of thinner films and rapid reduction of ligand-derived impurities. This is suitable for improving physical properties such as roughness and crystallinity.

Claims

1. An azeotropic mixture comprising a precursor compound that is spontaneously combustible at room temperature and a volatility modifier, characterized in that, The central metal of the precursor compound is selected from one or more of Al, Zn, Ga, and In. The volatility modifier is a substance that controls the volatility of the precursor compound, including one or more compounds selected from cyclic compounds having three or more element species containing lone pairs of electrons and linear compounds having three or more element species containing lone pairs of electrons.

2. The azeotropic mixture according to claim 1, characterized in that, The precursor compound is selected from one or more of Al(CH3)3, Al(CH2CH3)3, Zn(CH3)2, Zn(CH2CH3)2, Ga(CH3)3, Ga(CH2CH3)3, In(CH3)3, and In(CH2CH3)3.

3. The azeotropic mixture according to claim 1, characterized in that, The lone pair is selected from one or more of oxygen, sulfur, phosphorus, and nitrogen.

4. The azeotropic mixture according to claim 1, characterized in that, A cyclic compound having three or more elemental species containing the aforementioned lone pairs of electrons is a compound represented by the following chemical formula 1. [Chemical Formula 1] In the chemical formula 1, R' is hydrogen, an alkyl group having 1 to 5 carbon atoms, an olefinic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms, A is oxygen, sulfur, phosphorus, or nitrogen, and m is an integer from 0 to 2.

5. The azeotropic mixture according to claim 1, characterized in that, Linear compounds of elemental species having three or more lone pairs of electrons are compounds represented by the following chemical formula 2. [Chemical Formula 2] In the chemical formula 2, R” is hydrogen, an alkyl group having 1 to 5 carbon atoms, an olefinic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms, and B is -OH, -OCH3, -OCH2CH3, -CH2CH3, -SH, -SCH3, or -SCH2CH3.

6. The azeotropic mixture according to claim 1, characterized in that, The volatility modifier includes one or more compounds selected from the following chemical formulas 1-1 to 1-3 and 2-1 to 2-3. [Chemical Formulas 1-1 to 1-3] 、 、 [Chemical Formulas 2-1 to 2-3] 、 、 。 7. The azeotropic mixture according to claim 1, characterized in that, The azeotropic mixture contains inactive gases.

8. The azeotropic mixture according to claim 1, characterized in that, The precursor compound and the volatility modifier are contained in a weight ratio of 1:0.5 to 5.

9. The azeotropic mixture according to claim 1, characterized in that, The azeotropic mixture has a boiling point in the range of 40°C to 180°C, an APHA color value of 5 or less and a turbidity of 10 or less as determined by ASTM D 1209, a viscosity of 50 cP or less and a T0 value of 200°C or less.

10. A thin film deposition method, characterized in that, include: The step of laminating one or more films by using an azeotropic mixture according to any one of claims 1 to 9.

11. The thin film deposition method according to claim 10, characterized in that, The thin film deposition method includes: The step of injecting the azeotropic mixture onto a substrate loaded in a chamber to adjust the auto-ignition properties of the precursor compound; The step of removing unreacted azeotropic mixtures and byproducts by injecting an inert gas into the chamber; The steps of injecting nitriding gas, oxidizing gas, or reducing gas into the chamber to form a nitriding film, oxide film, or metal film of the central metal of the precursor compound; and The step of removing unreacted gases and byproducts by injecting an inactive gas into the chamber.

12. The thin film deposition method according to claim 11, characterized in that, The chamber is an atomic layer deposition chamber, a chemical vapor deposition chamber, a plasma-enhanced atomic layer deposition chamber, or a plasma-enhanced chemical vapor deposition chamber.

13. The thin film deposition method according to claim 11, characterized in that, The substrate is heated to 100°C to 700°C. The deposition method is carried out in the range of 100°C to 700°C.

14. The thin film deposition method according to claim 10, characterized in that, The film is formed by stacking aluminum nitride film, aluminum oxide film, aluminum metal film, zinc nitride film, zinc oxide film, or zinc metal film.

15. A thin film formed by the thin film deposition method according to claim 10, characterized in that, The thin film is a thin film formed by stacking nitride film, oxide film or metal film of the central metal.

16. The thin film according to claim 15, characterized in that, In the oxide film, the ratio of one or more group 13 central metals selected from Al, Ga and In to O, as determined by Auger electron spectroscopy, is in the range of 0.6 to 0.

75.

17. The thin film according to claim 15, characterized in that, In the oxide film, the ratio of the group 12 central metal of Zn to O, as determined by Auger electron spectroscopy, is in the range of 0.45 to 0.

55.

18. A semiconductor substrate, characterized in that, Includes the thin film according to claim 15.

19. A semiconductor device, characterized in that, Includes the semiconductor substrate according to claim 18.

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