Indium precursor compound, method for preparing same, and method for forming indium-containing film using same

Abstract

The present invention relates to an indium precursor compound, a composition thereof, and a method for forming an indium-containing thin film using same. The indium precursor compound exists in a liquid state at room temperature and has high thermal stability, thereby enabling formation of an excellent indium-containing film. In addition, the indium precursor compound has high volatility and thus is advantageous for large-area deposition, and has low reactivity with the atmosphere and thus is non-flammable and easy to handle, so that the indium precursor compound can be applied to various fields such as displays and semiconductors.

Description

Indium precursor compound, method for preparing the same, and method for forming an indium-containing film using the same

[0001] The present invention relates to an indium precursor compound, a method for producing the same, a precursor composition for forming an indium film comprising the same, an indium-containing film using the same, and a method for forming the same.

[0002]

[0003] Indium-based oxides are widely used in industry due to their transparency and electrical conductivity, suitable mobility, excellent uniformity, and outstanding optical transparency, and have achieved great success in conventional back-plane displays in particular.

[0004] In particular, since oxides containing indium have other advantages that can further increase conductivity, films of composite indium oxides containing indium and other metals or films of indium oxide doped with other elements are more commonly used than films of indium oxide containing only indium.

[0005] Oxide semiconductors, such as indium oxide (In2O3), Sn-doped and W-doped In2O3 (ITO and IWO), and indium-gallium-zinc-oxide (IGZO), are promising channel materials for back-end-of-line (BEOL) compatible transistors for monolithic 3D integration. In particular, the outlook for ALD In2O3 is very positive because it simultaneously boasts a low thermal budget of 225°C, an atomically smooth surface, highly controllable thickness down to the nanometer level, wafer-scale homogeneity and conformality, and high electron mobility exceeding 100㎠ / V·s. High-performance ALD In2O3 transistors have been demonstrated to deliver drive currents exceeding 2 mA / ㎛ with Enhancement-Mode operation and low Subthreshold Swing (SS) down to 63.8 mV / dec. The conformal capability of ALD for sidewalls, deep trenches, and other 3D structures opens up tremendous new opportunities for BEOL device processing and integration.

[0006] Meanwhile, in the memory and non-memory fields, product development is diversifying, including high aspect ratios and complex three-dimensional structures, and there is a demand for suitable indium and indium-containing films.

[0007] In order to form an In-based oxide film on a large-area substrate, especially on a large-area display substrate that can be applied to TVs, it is necessary to develop a liquid indium compound that is thermally stable above 200°C, and also to develop an In precursor for ALD that is suitable for new processes such as an in-situ process for forming composite films as well as an indium single film.

[0008] [Prior Art Literature]

[0009] (Patent Document 1) Korean Patent No. 10-1464715

[0010]

[0011] The present invention was designed to solve the problems of the above-mentioned prior art, and the technical problem to be solved by the present invention is to provide an indium precursor compound having a single structure, existing in a liquid state at room temperature, and having excellent thermal stability, so that a uniform and high-quality indium-containing film can be formed by atomic layer deposition (ALD), and further, a method for manufacturing the indium precursor compound in a safe and efficient manner. In addition, the present invention provides a method for depositing an indium-containing film by depositing the indium-containing film using the indium precursor compound.

[0012] However, the problems that the present invention seeks to solve are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0013] To achieve the above object, one embodiment provides an indium precursor compound represented by the following chemical formula 1:

[0014] [Chemical Formula 1]

[0015]

[0016] In the above chemical formula 1,

[0017] X is And,

[0018] Y is And,

[0019] R1 and R2 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups,

[0020] R3 to R8 are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group,

[0021] R a Inland R f are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group,

[0022] n is an integer from 0 to 2.

[0023] According to another embodiment of the present invention, a composition for forming an indium-containing film is provided, comprising the indium precursor compound.

[0024] In addition, according to another embodiment of the present invention, an indium-containing film formed using the indium precursor compound is provided.

[0025] Furthermore, according to another embodiment of the present invention, a method for depositing an indium-containing film is provided, comprising the step of depositing an indium-containing film on a substrate using the indium precursor compound.

[0026] An indium precursor compound according to one embodiment of the present invention exists in a liquid state at room temperature, making it easier to transport and handle within process equipment compared to solid precursors, and can effectively reduce concerns about process contamination due to residue accumulation. In particular, the indium precursor compound has significantly low reactivity with moisture or oxygen in the air, so there is no risk of self-ignition, and therefore, it has a clear advantage in handling and storage stability compared to existing commercial trimethylindium (TMI) precursors, which are solid and known to be pyrophoric.

[0027] The indium precursor compound of the present invention is suitable for the deposition of indium-based oxide thin films having these characteristics, and exhibits excellent volatility even at low temperatures, enabling the formation of uniform and high-quality indium-containing films on large-area substrates in processes such as ALD or CVD. In addition, due to its high thermal stability, it is stably supplied without decomposition or deterioration during the deposition process, enabling precise film composition and structural control. Therefore, the indium precursor compound of the present invention can improve both quality and process efficiency in the manufacturing process of memory and non-memory devices with complex structures and high aspect ratios.

[0028]

[0029] Figure 1 is a thermogravimetric analysis (TGA) graph of the compound of chemical formula 1-1 manufactured according to Example 1.

[0030] Figure 2 is a differential scanning calorimetry (DSC) graph of the compound of chemical formula 1-1 prepared according to Example 1.

[0031] Figure 3 is a graph showing the change in areal density on a substrate according to precursor feeding time according to Experimental Example 2.

[0032] Figure 4 is a graph showing the change in areal density on a substrate according to precursor purging time according to Experimental Example 2.

[0033] Figure 5 is a graph showing the change in areal density on a substrate according to the reactant feeding time according to Experimental Example 2.

[0034] Figure 6 is a graph showing the change in areal density on a substrate according to the reactant purging time according to Experimental Example 2.

[0035] Figure 7 is a graph showing the film thickness according to the process cycle when an indium-containing film was deposited according to Experimental Example 3.

[0036] Figure 8 is a diagram of a compound of chemical formula 1-1 manufactured according to Example 1. 1 This is a graph showing the H-NMR spectrum.

[0037]

[0038] Below, we will explain the present invention in more detail.

[0039] The advantages and features of the present invention, and methods for achieving them, will become clearer with reference to the embodiments described below. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms. These embodiments are provided solely to ensure complete disclosure of the present invention and to fully inform those skilled in the art of the scope of the invention. The present invention is defined solely by the scope of the claims.

[0040] Additionally, when it is said in this specification that a part is "on" another part, this includes not only cases where it is "directly on" the other part, but also cases where there is another part in between.

[0041] In this specification, when a part is said to "include" a certain component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0042] All numbers and expressions indicating the amounts of components, reaction conditions, etc. described in this specification should be understood to be modified by the term “about” in all cases unless otherwise specified.

[0043] In this specification, the terms “film” or “thin film” each mean both “film” and “thin film” unless specifically distinguished.

[0044] As used herein, the term "alkyl" or "alkyl group" includes linear or branched alkyl groups and all possible isomers thereof. For example, the alkyl group may include a methyl group (Me), an ethyl group (Et), an n-propyl group ( n Pr), iso-profiler ( i Pr), n-butyl group ( n Bu), tert-butyl group( t Bu), iso-butyl group( i Bu), sec-butyl group( sBu), pentyl group, hexyl group, isohexyl group, heptyl group, 4,4-dimethylpentyl group, octyl group, 2,2,4-trimethylpentyl group, nonyl group, decyl group, and isomers thereof, but may not be limited thereto.

[0045]

[0046] [Indium precursor compound]

[0047] According to one embodiment of the present invention, an indium precursor compound represented by the following chemical formula 1 is provided:

[0048] [Chemical Formula 1]

[0049]

[0050] In the above chemical formula 1,

[0051] X is And,

[0052] Y is And,

[0053] R1 and R2 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups,

[0054] R3 to R8 are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group,

[0055] R a Inland R f are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group,

[0056] n is an integer from 0 to 2.

[0057] In one embodiment of the present invention, in the chemical formula 1, R1 and R2 may each independently be a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an iso-butyl group, a sec-butyl group, or a tert-butyl group, but are not limited thereto.

[0058] In one embodiment of the present invention, in the chemical formula 1, R2 to R8 and Ra Inland R f may each independently be, but is not limited to, a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an iso-butyl group, a sec-butyl group, or a tert-butyl group.

[0059] Specifically, the indium precursor compound may include at least one selected from the group consisting of compounds represented by the following chemical formula:

[0060]

[0061]

[0062]

[0063]

[0064] The above indium precursor compound exists in a liquid state at room temperature and has excellent thermal stability, so that an indium-containing film can be easily formed by chemical vapor deposition (CVD) as well as atomic layer deposition (ALD).

[0065]

[0066] [Method for producing indium precursor compounds]

[0067] The indium precursor compound represented by the above chemical formula 1 can be prepared by the following reaction formula 1.

[0068] The method for producing an indium precursor compound represented by Chemical Formula 1 can be obtained by reacting an amine compound represented by Chemical Formula A of the following Reaction Scheme 1 with n-BuLi to produce a Li salt, reacting indium trichloride to obtain Chemical Formula B, and then sequentially reacting and purifying the compound of Chemical Formula B with Chemical Formula C and Chemical Formula D:

[0069] [Reaction Formula 1]

[0070]

[0071] In the above reaction formula 1, each substituent is as defined in chemical formula 1 above.

[0072] The molar ratio of the compound represented by the above chemical formula A and the compound of n-BuLi, InCl3 is 1:1:1, and the molar ratio of the sum of the compound represented by the above chemical formula A and the compounds represented by the chemical formulas C and D is preferably 1:2.

[0073] Specifically, 1 equivalent of the compound represented by the chemical formula A is added to a flask, cooled to -78°C, 1 equivalent of n-BuLi is added, the temperature is slowly raised to room temperature, and stirred for about 2 hours. Then, a DME solution in which 1 equivalent of InCl3 is dissolved is cooled to -20°C, the previous reactant is added, and the mixture is stirred at room temperature for 5 hours. The flask is cooled to 0°C again, and the compounds represented by the chemical formula C and the chemical formula D are added, and the mixture is reacted at room temperature for 15 hours or more to obtain the compound represented by the chemical formula 1. In addition, after the reaction is completed, a step of removing a salt generated during the reaction through a filtration process or the like, and distilling the solvent and volatile by-products under reduced pressure may be further included.

[0074] In one embodiment of the present invention, the method for preparing the indium precursor compound may be performed in a non-polar solvent such as pentane or hexane, or a polar solvent such as tetrahydrofuran, diethyl ether, or dichloromethane, but is not limited thereto.

[0075] In one embodiment of the present invention, the method for producing the indium precursor compound may be performed in an inert gas atmosphere such as nitrogen or argon to suppress reaction with moisture or oxygen, but is not limited thereto.

[0076]

[0077] [Precursor composition for forming indium-containing films]

[0078] According to one embodiment of the present invention, a composition for forming an indium film is provided, comprising an indium precursor compound represented by the above chemical formula 1.

[0079] In one embodiment of the present invention, the indium precursor compound may include at least one selected from the group consisting of compounds represented by the chemical formulas 1-1 to 1-39.

[0080] In one embodiment of the present invention, the indium-containing film may include at least one selected from the group consisting of an indium-containing metal film, an indium-containing oxide film, an indium-containing carbide film, an indium-containing sulfide film, and an indium-containing nitride film, but may not be limited thereto.

[0081] In one embodiment of the present invention, the indium-containing film may be deposited by chemical vapor deposition (CVD) or atomic layer deposition (ALD) using the precursor composition for forming the indium-containing film, but may not be limited thereto.

[0082] In one embodiment of the present invention, the indium-containing film forming precursor composition may be used to form an indium-containing film at a temperature range of room temperature to about 500°C, but may not be limited thereto.

[0083] In one embodiment of the present invention, the precursor composition for forming an indium-containing film can be used to deposit an indium-containing film having a thickness ranging from about 0.1 nm to about 500 nm, but may be applied in various ways depending on the intended use and may not be limited thereto.

[0084]

[0085] [Method for forming an indium-containing film]

[0086] According to one embodiment of the present invention, a method for forming an indium-containing film can be provided, including a step of depositing an indium-containing film using a composition for forming an indium-containing film including an indium precursor compound represented by the above chemical formula 1.

[0087] In one embodiment of the present invention, the indium precursor compound may include at least one selected from the group consisting of compounds represented by the chemical formulas 1-1 to 1-39.

[0088] In one embodiment of the present invention, the indium-containing film may include at least one selected from the group consisting of an indium-containing metal film, an indium-containing oxide film, an indium-containing carbide film, an indium-containing sulfide film, and an indium-containing nitride film, but may not be limited thereto.

[0089] In one embodiment of the present invention, the indium-containing film may be deposited by chemical vapor deposition (CVD) or atomic layer deposition (ALD), but may not be limited thereto.

[0090] In one embodiment of the present invention, chemical vapor deposition or atomic layer deposition may be performed using a deposition apparatus, deposition conditions, and one or more additional reactant gases known in the art, but may not be limited thereto.

[0091] In one embodiment of the present invention, the method for forming an indium-containing film includes, but is not limited to, supplying an indium-containing film forming composition including an indium precursor compound in a gaseous state to a substrate (substrate) located in a deposition chamber to form an indium-containing film on the surface of the substrate.

[0092] In one embodiment of the present invention, the indium-containing film may be formed at a temperature range of room temperature to about 500°C, but may not be limited thereto. For example, the indium-containing film may be formed at a temperature ranging from room temperature to about 500°C, from room temperature to about 450°C, from room temperature to about 400°C, from room temperature to about 350°C, from room temperature to about 300°C, from room temperature to about 250°C, from room temperature to about 200°C, from room temperature to about 150°C, from room temperature to about 100°C, from about 100°C to about 500°C, from about 100°C to about 450°C, from about 100°C to about 400°C, from about 100°C to about 350°C, from about 100°C to about 300°C, from about 100°C to about 250°C, from about 100°C to about 200°C, from about 100°C to about 150°C, from about 150°C to about 500°C, from about 150°C to about 450°C, from about 150°C to about 400°C, about 150°C to about 350°C, about 150°C to about 300°C, about 150°C to about 250°C, about 150°C to about 200°C, about 200°C to about 500°C, about 200°C to about 450°C, about 200°C to about 400°C, about 200°C to about 350°C, about 200°C to about 300°C, about 200°C to about 250°C, about 250°C to about 500°C, about 250°C to about 450°C, about 250°C to about 400°C, about 250°C to about 350°C, about 250°C to about 300°C, about 300°C to about 500°C, about 300°C to about It may be formed at a temperature range of, but is not limited to, 450°C, about 300°C to about 400°C, about 300°C to about 350°C, about 350°C to about 500°C, about 350°C to about 450°C, about 350°C to about 400°C, about 400°C to about 500°C, about 400°C to about 450°C, or about 450°C to about 500°C.In one embodiment of the present invention, the indium-containing film may be formed at a temperature range of about 200°C to about 400°C, or about 300°C to about 400°C.

[0093] In one embodiment of the present invention, the indium-containing film may be formed in a thickness range of about 0.1 nm to about 500 nm, but may be applied in various ways depending on the application and may not be limited thereto. For example, the indium-containing film may have a thickness of about 0.1 nm to about 500 nm, about 0.1 nm to about 400 nm, about 0.1 nm to about 300 nm, about 0.1 nm to about 200 nm, about 0.1 nm to about 100 nm, about 0.1 nm to about 50 nm, about 0.1 nm to about 40 nm, about 0.1 nm to about 30 nm, about 0.1 nm to about 20 nm, about 0.1 nm to about 10 nm, about 1 nm to about 500 nm, about 1 nm to about 400 nm, about 1 nm to about 300 nm, about 1 nm to about 200 nm, about 1 nm to about 100 nm, about 1 nm to about 50 nm, about 1 nm to about 40 nm, about 1 nm to about 30 nm, about 1 nm About 20 nm, About 1 nm to about 10 nm, About 10 nm to about 500 nm, About 10 nm to about 400 nm, About 10 nm to about 300 nm, About 10 nm to about 200 nm, About 10 nm to about 100 nm, About 10 nm to about 50 nm, About 10 nm to about 40 nm, About 10 nm to about 30 nm, About 10 nm to about 20 nm, About 20 nm to about 500 nm, About 20 nm to about 400 nm, About 20 nm to about 300 nm, About 20 nm to about 200 nm, About 20 nm to about 100 nm, About 20 nm to about 50 nm, About 20 nm to about 40 nm, About 20 nm to about 30 nm, About 30 nm to about 500 nm, About 30 nm to about 400 nm, about 30 nm to about 300 nm, about 30 nm to about 200 nm, about 30 nm to about 100 nm,About 30 nm to about 50 nm, about 30 nm to about 40 nm, about 40 nm to about 500 nm, about 40 nm to about 400 nm, about 40 nm to about 300 nm, about 40 nm to about 200 nm, about 40 nm to about 100 nm, about 40 nm to about 50 nm, about 50 nm to about 500 nm, about 50 nm to about 400 nm, about 50 nm to about 300 nm, about 50 nm to about 200 nm, about 50 nm to about 100 nm, about 100 nm to about 500 nm, about 100 nm to about 400 nm, about 100 nm to about 300 nm, about 100 nm to about 200 nm, about 200 nm to about 500 nm, about 200 nm to It may be formed in a thickness range of about 400 nm, about 200 nm to about 300 nm, about 300 nm to about 500 nm, about 300 nm to about 400 nm, or about 400 nm to about 500 nm, but may not be limited thereto.

[0094] In one embodiment of the present invention, the indium-containing film may be formed on one or more substrates selected from, but not limited to, conventional silicon semiconductor wafers, compound semiconductor wafers, and plastic substrates (PI, PET, PES, and PEN). In addition, a substrate having holes or grooves may be used, and a porous substrate having a large surface area may be used, but not limited to. In addition, the indium-containing film may be formed on all or part of two or more different types of substrates in contact or connection simultaneously or sequentially, but not limited to.

[0095] In one embodiment of the present invention, the indium-containing film may be formed on a substrate including one or more protrusions (grooves) having an aspect ratio of about 1 or more, for example, about 1 to about 100, and a width of about 1 μm or less, for example, about 10 nm to about 1 μm, but may not be limited thereto. The protrusions (grooves) may be in the form of holes or trenches.

[0096] For example, the aspect ratio is about 1 or more, about 10 or more, about 30 or more, about 50 or more, about 1 to about 100, about 1 to about 90, about 1 to about 80, about 1 to about 70, about 1 to about 60, about 1 to about 50, about 1 to about 40, about 1 to about 30, about 1 to about 20, about 1 to about 10, about 10 to about 100, about 10 to about 90, about 10 to about 80, about 10 to about 70, about 10 to about 60, about 10 to about 50, about 10 to about 40, about 10 to about 30, about 10 to about 20, about 20 to about 100, about 20 to about 90, about 20 to about 80, About 20 to about 70, about 20 to about 60, about 20 to about 50, about 20 to about 40, about 20 to about 30, about 30 to about 100, about 30 to about 90, about 30 to about 80, about 30 to about 70, about 30 to about 60, about 30 to about 50, about 30 to about 40, about 40 to about 100, about 40 to about 90, about 40 to about 80, about 40 to about 70, about 40 to about 60, about 40 to about 50, about 50 to about 100, about 50 to about 90, about 50 to about 80, about 50 to about 70, about 50 to about 60, about 60 to about 100, about It may be, but is not limited to, about 60 to about 90, about 60 to about 80, about 60 to about 70, about 70 to about 100, about 70 to about 90, about 70 to about 80, about 80 to about 100, about 80 to about 90, or about 90 to about 100.

[0097] Also, for example, the width is 1 ㎛ or less, about 10 nm to about 1 ㎛, about 10 nm to about 900 nm, about 10 nm to about 800 nm, about 10 nm to about 700 nm, about 10 nm to about 600 nm, about 10 nm to about 500 nm, about 10 nm to about 400 nm, about 10 nm to about 300 nm, about 10 nm to about 200 nm, about 10 nm to about 100 nm, about 10 nm to about 90 nm, about 10 nm to about 80 nm, about 10 nm to about 70 nm, about 10 nm to about 60 nm, about 10 to about 50 nm, about 10 nm to about 40 nm, about 10 nm to about 30 nm, about 10 nm to about 20 nm, about 20 nm About 1 ㎛, about 20 nm to about 900 nm, about 20 nm to about 800 nm, about 20 nm to about 700 nm, about 20 nm to about 600 nm, about 20 nm to about 500 nm, about 20 nm to about 400 nm, about 20 nm to about 300 nm, about 20 nm to about 200 nm, about 20 nm to about 100 nm, about 20 nm to about 90 nm, about 20 nm to about 80 nm, about 20 nm to about 70 nm, about 20 nm to about 60 nm, about 20 nm to about 50 nm, about 20 nm to about 40 nm, about 20 nm to about 30 nm, about 30 nm to about 1 ㎛, about 30 nm to about 900 nm, about 30 nm to about 800 nm, About 30 nm to about 700 nm, about 30 nm to about 600 nm, about 30 nm to about 500 nm, about 30 nm to about 400 nm, about 30 nm to about 300 nm, about 30 nm to about 200 nm, about 30 nm to about 100 nm, about 30 nm to about 90 nm, about 30 nm to about 80 nm,About 30 nm to about 70 nm, about 30 nm to about 60 nm, about 30 nm to about 50 nm, about 30 nm to about 40 nm, about 40 nm to about 1 μm, about 40 nm to about 900 nm, about 40 nm to about 800 nm, about 40 nm to about 700 nm, about 40 nm to about 600 nm, about 40 nm to about 500 nm, about 40 nm to about 400 nm, about 40 nm to about 300 nm, about 40 nm to about 200 nm, about 40 nm to about 100 nm, about 40 nm to about 90 nm, about 40 nm to about 80 nm, about 40 nm to about 70 nm, about 40 nm to about 60 nm, about 40 nm to about 50 nm, about 50 nm to about 1 ㎛, about 50 nm to about 900 nm, about 50 nm to about 800 nm, about 50 nm to about 700 nm, about 50 nm to about 600 nm, about 50 nm to about 500 nm, about 50 nm to about 400 nm, about 50 nm to about 300 nm, about 50 nm to about 200 nm, about 50 nm to about 100 nm, about 50 nm to about 90 nm, about 50 nm to about 80 nm, about 50 nm to about 70 nm, about 50 nm to about 60 nm, about 100 nm to about 1 ㎛, about 100 nm to about 900 nm, about 100 nm to about 800 nm, about 100 nm to about 700 nm, about 100 nm to about 600 nm, about 100 nm to About 500 nm, about 100 nm to about 400 nm, about 100 nm to about 300 nm, about 100 nm to about 200 nm, about 200 nm to about 1 ㎛, about 200 nm to about 900 nm, about 200 nm to about 800 nm, about 200 nm to about 700 nm, about 200 nm to about 600 nm, about 200 nm to about 500 nm,About 200 nm to about 400 nm, about 200 nm to about 300 nm, about 300 nm to about 1 μm, about 300 nm to about 900 nm, about 300 nm to about 800 nm, about 300 nm to about 700 nm, about 300 nm to about 600 nm, about 300 nm to about 500 nm, about 300 nm to about 400 nm, about 400 nm to about 1 μm, about 400 nm to about 900 nm, about 400 nm to about 800 nm, about 400 nm to about 700 nm, about 400 nm to about 600 nm, about 400 nm to about 500 nm, about 500 nm to about 1 μm, about 500 nm to about 900 nm, about 500 nm to about It may be, but is not limited to, about 800 nm, about 500 nm to about 700 nm, about 500 nm to about 600 nm, about 600 nm to about 1 μm, about 600 nm to about 900 nm, about 600 nm to about 800 nm, about 600 nm to about 700 nm, about 700 nm to about 1 μm, about 700 nm to about 900 nm, about 700 nm to about 800 nm, about 800 nm to about 1 μm, about 800 nm to about 900 nm, or about 900 nm to about 1 μm.

[0098] In one embodiment of the present invention, the indium precursor compound of the present invention included in the film-forming composition can be used as a precursor of an atomic layer deposition method or a chemical vapor deposition method to form an indium-containing film due to its low density and high thermal stability, and in particular, can uniformly form an indium-containing film having a thickness of several μm to several tens of nm on a substrate having a pattern (groove) on the surface, a porous substrate, or a plastic substrate, in a temperature range of from room temperature to about 500°C, from about 200°C to about 400°C, from about 300°C to about 400°C, from room temperature to about 500°C, from about 200°C to about 500°C, or from about 300°C to about 500°C, and including the surface of the deepest part of the fine pattern (groove) and the upper surface of the fine unevenness (groove) having an aspect ratio of from about 1 to about 100, or from about 1 to about 50, and a width of from about 1 μm to about 10 nm or less. It has an excellent effect of being able to uniformly form an indium-containing oxide film or nitride film having a thickness of several μm to several tens of nm on the entire surface of the substrate, including the surface of fine irregularities (grooves).

[0099] In one embodiment of the present invention, the method for forming the indium-containing film preferably comprises accommodating a substrate (substrate) in a reaction chamber, and then transporting the indium precursor compound onto the substrate using a carrier gas or a diluting gas to deposit an indium-containing oxide film or nitride film at a wide range of deposition temperatures from room temperature to about 500°C, or from about 200°C to about 400°C. However, the present invention may not be limited thereto.

[0100] In one embodiment of the present invention, the deposition temperature is from room temperature to about 500°C, or from about 200°C to about 400°C, because the process temperature that can be applied to memory devices, logic devices, and display devices is wide, so that the film has a high applicability to various fields, and because the film characteristics of indium-containing oxide thin films or nitride thin films are different, an indium precursor compound that can be used in a wide temperature range is required, so that the deposition is preferably performed at a deposition temperature range of from room temperature to about 500°C, or from about 200°C to about 400°C. However, it may not be limited thereto.

[0101] In one embodiment of the present invention, it is preferable to use one or more mixed gases selected from argon (Ar), nitrogen (N2), helium (He), or hydrogen (H2) as the carrier gas or diluting gas. However, the present invention may not be limited thereto.

[0102] In one embodiment of the present invention, the method for forming the indium-containing film may include a step of supplying the indium precursor compound into a reaction chamber using a method including at least one selected from the group consisting of a bubbling method, a liquid delivery system (LDS) method, a vapor flow control (VFC) method, and a bypass method.

[0103] In one embodiment of the present invention, the method for forming the indium-containing film may include a step of supplying the indium precursor compound into the reaction chamber using a method including at least one selected from the group consisting of a bubbling method for forcibly vaporizing the precursor compound using a carrier gas, a liquid delivery system (LDS) method for supplying the precursor compound in a liquid state at room temperature and vaporizing it through a vaporizer, and a vapor flow controller (VFC) method for directly supplying the precursor compound using the vapor pressure of the precursor.

[0104] For example, when the vapor pressure is high, the VFC method can be used, and when the vapor pressure is low, the bypass method, which heats the container to vaporize, can be used.

[0105] The step of supplying the above indium precursor compound into the reaction chamber can be performed using a carrier gas or dilution gas in a temperature range of 0.1 to 10 torr and room temperature to 150°C.

[0106] For example, a method may be used in which the indium precursor compound is placed in a bubbler container or a VFC container and supplied into the chamber by bubbling or transporting it with a carrier gas at a temperature range of about 0.1 torr to about 10 torr and room temperature to about 150°C using high vapor pressure. Most preferably, an LDS method may be used in which the indium precursor compound is supplied in a liquid state at room temperature and vaporized through a vaporizer. However, the present invention may not be limited thereto.

[0107] In one embodiment of the present invention, it is more preferable to transport the indium precursor compound using argon (Ar) or nitrogen (N2) gas, use thermal energy or plasma, or apply a bias to the substrate to vaporize the indium precursor compound. However, the present invention may not be limited thereto.

[0108] In one embodiment of the present invention, during the deposition, thermal energy or plasma may be used, or a bias may be applied to the substrate.

[0109] In one embodiment of the present invention, when depositing the indium-containing film, at least one selected from the group consisting of nitrogen (N2), nitrogen plasma (N2Plasma), ammonia (NH3), ammonia plasma (NH3Plasma), hydrazine (N2H4), dimethyl hydrazine (C2H8N2), hydrogen (H2), hydrogen plasma (H2Plasma), water vapor (H2O), oxygen (O2), oxygen plasma (O2Plasma), nitric oxide (NO, N2O), nitric oxide plasma (N2O Plasma), oxygen nitride (N2O2), hydrogen peroxide (H2O2), and ozone (O3) may be used.

[0110] Specifically, in order to form an indium-containing nitride film (InN) during the deposition of the indium-containing film, it is preferable to use ammonia (NH3), ammonia plasma (NH3Plasma), hydrazine (N2H4), or nitrogen plasma (N2Plasma) as the reaction gas. However, it may not be limited thereto.

[0111] In one embodiment of the present invention, when depositing the indium-containing film, in order to form the indium-containing oxide film (In2O3), it is preferable to use one or a mixture of two or more selected from water vapor (H2O), oxygen (O2), oxygen plasma (O2Plasma), nitrogen oxide (NO, N2O), nitrogen oxide plasma (N2O Plasma), oxygen nitride (N2O2), hydrogen peroxide (H2O2), and ozone (O3) as a reaction gas. However, it may not be limited thereto.

[0112] The present invention is described in more detail by the following examples. The following examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

[0113]

[0114] Example

[0115] <Example 1> Preparation of [(CH3)2NCH2CH2NSi(CH3)3]In(CH3)2

[0116] [Chemical Formula 1-1]

[0117]

[0118] In a flame-dried 1 L Schlenk flask, approximately 150.0 g (0.90 mol) of ligand (CH3)2NCH2CH2NHSi(CH3)3 and approximately 251.8 g (0.90 mol) of n-BuLi were reacted at -78°C, slowly warmed to room temperature, and reacted for 2 hours. In another flame-dried 5 L Schlenk flask, 200.0 g (0.90 mol) of InCl3 dissolved in DME solution was cooled to -20°C, (CH3)2NCH2CH2NLiSi(CH3)3 solution was added, and slowly warmed to room temperature, and stirred for 5 hours. This was cooled to 0°C again, 607 mL (1.80 mol) of 3 M methylmagnesium chloride was added, and the reaction was terminated by stirring at room temperature for 15 hours. After the above reaction was completed, the salt produced during the reaction was removed through a filtration process, and the solvent and volatile by-products were distilled under reduced pressure to obtain about 205.0 g (yield: about 74.5%, based on InCl3) of a colorless, transparent liquid of the chemical formula 1-1.

[0119]

[0120]

[0121] <Example 2> Preparation of [(CH3)2NCH2CH2CH2NSi(CH3)3]In(CH3)2

[0122] [Chemical Formula 1-2]

[0123]

[0124] In a flame-dried 250 mL Schlenk flask, about 15.0 g (0.086 mol) of ligand (CH3)2NCH2CH2CH2NHSi(CH3)3 and about 24.0 g (0.086 mol) of n-BuLi were reacted at -78°C, slowly warmed to room temperature, and reacted for 2 hours. In another flame-dried 500 mL Schlenk flask, 19.0 g (0.086 mol) of InCl3 dissolved in DME solution was cooled to -20°C, (CH3)2NCH2CH2CH2NLiSi(CH3)3 solution was added, and slowly warmed to room temperature, and stirred for 5 hours. This was cooled to 0°C again, 57.3 mL (0.17 mol) of 3 M methylmagnesium chloride was added, and the reaction was terminated by stirring at room temperature for 16 hours. After the above reaction was completed, the salt produced during the reaction was removed through a filtration process, and the solvent and volatile by-products were distilled under reduced pressure to obtain about 21.9 g (yield: about 80.0%, based on InCl3) of a colorless, transparent liquid of the chemical formula 1-2.

[0125]

[0126]

[0127] <Example 3> Preparation of [CH3OCH2CH2CH2NSi(CH3)3]In(CH3)2

[0128] [Chemical Formula 1-3]

[0129]

[0130] In a flame-dried 500 mL Schlenk flask, about 35.0 g (0.22 mol) of ligand CH3OCH2CH2CH2NHSi(CH3)3 and about 50.4 g (0.18 mol) of n-BuLi were reacted at -78°C, slowly warmed to room temperature, and reacted for 2 hours. In another flame-dried 1 L Schlenk flask, 40.0 g (0.18 mol) of InCl3 was dissolved in DME, cooled to -20°C, and then CH3OCH2CH2CH2NLiSi(CH3)3 solution was added, slowly warmed to room temperature, and stirred for 15 hours. This was cooled to 0°C again, 120.5 mL (0.36 mol) of 3 M methylmagnesium chloride was added, and the reaction was terminated by stirring at room temperature for 16 hours. After the above reaction was completed, the salt produced during the reaction was removed through a filtration process, and the solvent and volatile by-products were distilled under reduced pressure to obtain about 38.0 g (yield: about 68.9%, based on InCl3) of the above chemical formula 1-3.

[0131]

[0132]

[0133] <Example 4> Preparation of [CH3OCH2CH2CH2NSi(CH3)3]In(CH2CH3)2

[0134] [Chemical Formula 1-4]

[0135]

[0136] In a flame-dried 250 mL Schlenk flask, about 30.0 g (0.18 mol) of ligand CH3OCH2CH2CH2NHSi(CH3)3 and about 43.2 g (0.16 mol) of n-BuLi were reacted at -78°C, slowly warmed to room temperature, and reacted for 4 hours. In another flame-dried 1 L Schlenk flask, 34.3 g (0.16 mol) of InCl3 was dissolved in DME, cooled to -20°C, and then CH3OCH2CH2CH2NLiSi(CH3)3 solution was added, slowly warmed to room temperature, and stirred for 15 hours. This was cooled to 0°C again, 155.0 mL (0.31 mol) of 3 M ethylmagnesium chloride was added, and the reaction was terminated by stirring at room temperature for 16 hours. After the above reaction was completed, the salt produced during the reaction was removed through a filtration process, and the solvent and volatile by-products were distilled under reduced pressure to obtain about 34.0 g (yield: about 65.8%, based on InCl3) of the above chemical formula 1-4.

[0137]

[0138]

[0139] Experimental example

[0140] <Experimental Example 1> Analysis of thermal properties of indium precursor compounds

[0141] In order to evaluate the volatility and thermal stability of the indium precursor compound manufactured in Example 1, thermal gravimetry analysis (TGA) and differential scanning calorimetry (DSC) analysis were performed, and the results are shown in Figures 1 and 2 below.

[0142] As can be seen in FIGS. 1 and 2, the indium precursor compound manufactured by the method of Example 1 was completely vaporized without leaving any residue as the temperature increased, and it was confirmed that thermal decomposition occurred at 310°C. From this, it can be seen that it is thermally stable and suitable for use as an indium precursor for forming an indium-containing film using chemical vapor deposition (CVD) or atomic layer deposition (ALD).

[0143]

[0144] <Experimental Example 2> Experiment to optimize the deposition conditions of indium precursor compounds to confirm the saturation conditions of the ALD process.

[0145] Using the indium precursor compound of Example 1, the saturation conditions for each process step (precursor supply - precursor purge - reactant supply - reactant purge) in the atomic layer deposition (ALD) process were confirmed, and optimized process conditions were derived based on this.

[0146] The indium precursor compound was stored in a stainless steel vessel and heated to 35°C for use, and the process pressure was maintained at 1.5–1.8 Torr. The precursor was supplied to the reaction chamber using approximately 300 sccm of argon (Ar) carrier gas, and reaction byproducts and residual precursor were removed in the purge step using argon (Ar) gas at a flow rate of 600 sccm. Ozone (O₃) was used as the oxidizer.

[0147] Experiments to derive saturation conditions were performed at a process temperature of 210°C, with the time of each process step set as a variable and the remaining three process steps set to fixed times. The growth amount of the thin film was evaluated as the mass per unit area (areal density, μg / cm²). The detailed conditions and results of each experiment are shown in Table 1 and Figures 3 to 6.

[0148] As can be seen in Table 1 and Figures 3 to 6, the supply time of the indium precursor compound showed a tendency for the thin film growth amount to be saturated when it was about 15 seconds or longer, and no additional growth change was observed when the purge time was about 10 seconds or longer. The ozone supply time was saturated when it was about 5 seconds or longer, and no change in the growth amount was observed when the subsequent ozone purge time was about 15 seconds or longer.

[0149] The optimal process step sequence established based on the derived saturation conditions is 15-10-5-15 sec, and the conditions were utilized as ALD process conditions that can induce a stable deposition rate and linear film thickness increase when forming an indium precursor-based oxide film.

[0150]

[0151]

[0152] <Experimental Example 3> Analysis of the Deposition Characteristics of Indium-Containing Oxide Films from Indium Precursor Compounds Using the Atomic Layer Deposition (ALD) Process

[0153] The deposition characteristics of an indium-containing oxide film were analyzed through an atomic layer deposition (ALD) process using the indium precursor compound of Example 1.

[0154] The indium precursor compound of Example 1 was used after being placed in a stainless steel container and heated to 35℃. The process pressure of the reactor was maintained at 1.5 to 1.8 torr, and the precursor compound was supplied to the reaction chamber in a gaseous state using an argon (Ar) carrier gas of about 300 sccm, and purged using argon (Ar) gas having a flow rate of 600 sccm to form an indium-containing oxide film on a SiO2 substrate and evaluate its characteristics. In this experimental example, the deposition process was performed by applying the optimal ALD sequence conditions derived from Experimental Example 2, 15-10-5-15 sec (precursor supply - precursor purge - reactant supply - reactant purge). The process conditions are summarized in Table 2.

[0155] As shown in Table 2, the deposition characteristics of the indium-containing oxide film of the indium precursor compound were analyzed by repeating the gas supply cycle consisting of supplying an indium precursor compound to a SiO2 substrate at a process temperature of 210°C for about 15 seconds → supplying argon (Ar) gas for about 10 seconds to remove the indium precursor compound (gas) remaining in the reactor → supplying ozone (O3) as a reaction gas for about 5 seconds → supplying argon (Ar) gas for about 15 seconds to remove the ozone (O3) gas remaining in the reactor. The results are shown in Fig. 7 below.

[0156] As can be seen in Fig. 7, based on the ALD process conditions (15-10-5-15 sec sequence) applied in this example, a total of 200 cycles of deposition were performed, and as the process cycle increased, the thickness of the indium-containing oxide film showed a tendency to increase linearly, and the thickness increase per cycle, i.e., the Growth Per Cycle (GPC), was calculated to be approximately 0.047 nm / cycle (0.47 Å / cycle; 10 Å = 1 nm).

[0157] In particular, the consistent growth pattern without significant fluctuations in growth rate across both the initial and later cycles suggests that the derived optimal sequence stably maintains reaction saturation conditions and sufficiently completes the surface reaction even with repeated precursor and oxidant supply processes. These results demonstrate that the indium precursor compound offers excellent linearity and deposition control characteristics within the ALD process, supporting its potential as a precursor for forming high-quality indium-containing oxide films.

[0158]

[0159]

Claims

1. An indium precursor compound represented by the following chemical formula 1: [Chemical Formula 1] In the above chemical formula 1, X is And, Y is And, R1 and R2 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups, R3 to R8 are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group, R a Inland R f are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group, n is an integer from 0 to 2.

2. In paragraph 1, An indium precursor compound, which is a compound represented by one of the following chemical formulas:

3. A composition for forming an indium-containing film, comprising an indium precursor compound represented by the following chemical formula 1 and used for depositing an indium-containing film: [Chemical Formula 1] In the above chemical formula 1, X is And, Y is And, R1 and R2 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups, R3 to R8 are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group, R a Inland R f are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group, n is an integer from 0 to 2.

4. In paragraph 3, A composition for forming an indium-containing film, wherein the indium precursor compound comprises at least one selected from the group consisting of compounds represented by the following chemical formula:

5. A method for forming an indium-containing film, comprising the step of depositing an indium-containing film using a composition for forming an indium-containing film including an indium precursor compound represented by the following chemical formula 1: [Chemical Formula 1] In the above chemical formula 1, X is And, Y is And, R1 and R2 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups, R3 to R8 are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group, R a Inland R f are each independently selected from the group consisting of a hydrogen atom and a linear or branched C1-C4 alkyl group, n is an integer from 0 to 2.

6. In paragraph 5, A method for forming an indium-containing film, wherein the indium precursor compound comprises at least one selected from the group consisting of compounds represented by the following chemical formula:

7. In paragraph 5, The above indium-containing film includes at least one selected from the group consisting of an indium-containing metal film, an indium-containing oxide film, an indium-containing sulfide film, an indium-containing nitride film, and an indium-containing carbide film. A method for forming an indium-containing film, wherein, during the above deposition, at least one selected from the group consisting of nitrogen (N2), nitrogen plasma (N2Plasma), ammonia (NH3), ammonia plasma (NH3Plasma), hydrazine (N2H4), dimethyl hydrazine (C2H8N2), hydrogen (H2), hydrogen plasma (H2Plasma), water vapor (H2O), oxygen (O2), oxygen plasma (O2Plasma), nitric oxide (NO, N2O), nitric oxide plasma (N2O Plasma), oxygen nitride (N2O2), hydrogen peroxide (H2O2), and ozone (O3) is used.

8. In paragraph 5, A method for forming an indium-containing film, wherein the indium-containing film is deposited by chemical vapor deposition (CVD) or atomic layer deposition (ALD).

9. In paragraph 5, A method for forming an indium-containing film, comprising a step of supplying the indium precursor compound into a reaction chamber using a method including at least one selected from the group consisting of a bubbling method, a liquid delivery system (LDS) method, a vapor flow control (VFC) method, and a bypass method.

10. In paragraph 9, A method for forming an indium-containing film, wherein the step of supplying the indium precursor compound into the reaction chamber is performed using a carrier gas or a diluting gas in a pressure range of 0.1 to 10 torr and a temperature range of room temperature to 150°C.

11. In paragraph 5, A method for forming an indium-containing film, wherein the indium-containing film is formed at a temperature range of room temperature to 500°C.

12. In paragraph 5, A method for forming an indium-containing film, wherein the indium-containing film is formed in a thickness range of 0.1 nm to 500 nm.

13. In paragraph 5, A method for forming an indium-containing film, wherein the indium-containing film is formed on a substrate including one or more unevennesses having an aspect ratio of 1 or more and a width of 1 ㎛ or less.

14. In paragraph 5, A method for forming an indium-containing film, wherein thermal energy or plasma is used during the above deposition, or a bias is applied to the substrate.

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