KR20240093325A - Gallium compound, composition for depositing thin film comprising the same, and a process for producing the thin film using the same - Google Patents

Abstract

The present invention relates to a gallium compound, a method for producing the same, a composition for thin film deposition containing the same, and a method for producing a thin film using the same. The gallium compound of the present invention has excellent volatility and stability and is very useful as a precursor for a gallium-containing thin film. Due to excellent adsorption with the substrate, higher quality gallium-containing thin films can be produced.

Description

Gallium compound, composition for depositing thin film comprising the same, and method for producing a thin film using the same {Gallium compound, composition for depositing thin film comprising the same, and a process for producing the thin film using the same}

The present invention relates to a gallium compound, a composition for depositing a thin film containing the same, and a method for manufacturing a thin film using the same. More specifically, it relates to a gallium compound useful as a precursor for depositing a gallium-containing thin film, a composition for depositing a gallium-containing thin film containing the same, and the same. It relates to a method of manufacturing a gallium-containing thin film using this method.

The development of new technologies and materials in the semiconductor industry has made possible miniaturization, high reliability, high speed, high functionality, and high integration of devices such as semiconductor integrated circuits. Accordingly, the properties required for precursors to form thin films have also changed. In general, the characteristics required for a thin film deposition precursor are a gas or liquid compound with high vapor pressure, excellent thermal stability, and easy transfer to the deposition chamber, and furthermore, reactivity with the reaction gases used depending on the type of thin film being manufactured. must also be excellent.

Additionally, thin film formation methods used in the manufacture of semiconductor devices include physical vapor growth method (PVD method) and chemical vapor growth method (CVD method) by sputtering. However, in the next generation of semiconductor manufacturing, a uniform thin film is required even on the surface of a complex three-dimensional structure of a miniaturized device, so the PVD method is not suitable because it is difficult to form a uniform film on the uneven surface.

Accordingly, as a method of forming a thin film with excellent step coverage, a CVD method in which raw materials are transferred to a reaction tank as a gas and decomposed to form a film, or an atomic layer deposition (ALD) method in which raw materials adsorbed on the substrate surface are decomposed and a film is deposited ) Thin film formation method has been reviewed and is mainly used.

Meanwhile, precursors containing Group 13 metals have excellent stability and conductivity, and are attracting attention as precursors for thin film deposition. In particular, group 13 metal oxides can be used as transparent oxide semiconductor materials and can be applied as electrodes, conductive coating materials, etc.

Gallium oxide (Ga ₂ O ₃ ), which contains gallium among group 13 metals, has a wide band gap energy and is used in display fields such as gas sensors and transparent conductors, as well as next-generation solar cells, specifically phosphor raw materials, semiconductors, and CIGS (copper). indium gallium selenide) It is used as a material applicable to solar cells, ultra-thin liquid crystal displays (TFT-LCD), and organic light-emitting diodes (OLED). In addition, gallium oxide is an electrical insulator at room temperature and a semiconductor at temperatures above 500°C, having a chemically and thermally stable monoclinic form.

Trimethylgallium (TMG) is the most widely used gallium precursor, but it is very sensitive to air and ignites spontaneously when exposed, making it difficult to handle. In addition, gallium complexes such as [Ga(hfac)]3 (hfac = hexafluoroacetylacetonate) and [Ga(OCH(CF3)2)3(HNMe2)] have been reported, but they contain halogen elements, especially fluorine, so they are difficult to deposit when depositing thin films. Gallium fluoride (GaF) is formed due to fluorine, causing contamination in the thin film, which can cause serious deterioration of device characteristics and reliability problems during the semiconductor device process. In addition, gallium alkoxide dimers or tetramers were reported, but they did not correspond to a single monomer and had low volatility to be used as a precursor for thin film deposition.

Precursors for thin film deposition necessarily require high volatility and thermal stability, but previously reported gallium compounds have insufficient volatility to be used as precursors or have problems of contaminating thin films with halogen elements, including halogen elements. .

Therefore, it is less reactive in moisture or air, so there is no risk of spontaneous combustion and is easy to handle. The compound itself does not contain halogen elements such as fluorine, but contains gallium that can be applied to ALD and CVD processes with high volatility and thermal stability. There is a need for the development of precursors for thin film deposition.

KR 10-2017-0058765 A

The present invention provides a gallium compound that has improved volatility and thermal stability and is very useful for producing high-quality gallium-containing thin films, and a method for producing the same.

Additionally, the present invention provides a composition for depositing a gallium-containing thin film containing the gallium compound of the present invention.

Additionally, the present invention provides a method for producing a gallium-containing thin film using the gallium compound or the composition for depositing a gallium-containing thin film of the present invention.

One aspect of the present invention provides a composition for depositing a gallium-containing thin film containing a gallium compound represented by Formula 1, which has excellent volatility and stability and is very useful as a precursor for a gallium-containing thin film, and a method of forming a gallium-containing thin film using the same.

[Formula 1]

In Formula 1,

R ¹ and R ² are each independently C1-C10 alkyl, C3-C10 cycloalkyl, or -NR ^a R ^b ;

R ^a and R ^b are independently C1-C10 alkyl or C3-C10 cycloalkyl;

R ³ and R ⁴ are independently C1-C10 alkyl or C3-C10 cycloalkyl.

Another aspect of the present invention provides a method of forming a gallium-containing thin film using a gallium compound represented by Formula 1 according to an embodiment.

Another aspect of the present invention is to provide a gallium compound that is very useful as a precursor for gallium-containing thin films due to its excellent volatility and stability. The gallium compound of the present invention is represented by the following formula (2).

[Formula 2]

In Formula 2,

R ¹¹ to R ¹⁶ are independently C1-C10 alkyl or C3-C10 cycloalkyl.

The new gallium compound according to the present invention has good thermal stability, high volatility, and excellent cohesion, so it is useful as a precursor for gallium-containing thin films. Furthermore, it has excellent adsorption with a substrate, making it possible to produce higher quality gallium-containing thin films. In addition, the new gallium compound according to the present invention exists in a solid or liquid state at room temperature and pressure that can be handled, making it easy to handle. In addition, since the new gallium compound according to the present invention exists in a solid or liquid state at room temperature, it is supplied at a uniform concentration to a large-area substrate and has excellent thin film thickness uniformity. In addition, the new gallium compound according to the present invention has a high It does not decompose even at processing temperatures and has excellent storage stability.

In addition, the composition for depositing a gallium-containing thin film of the present invention contains a gallium compound with high thermal stability and reactivity as a precursor, so that when manufacturing a gallium-containing thin film, it has excellent cohesion at a high deposition rate and can produce a uniform thin film with high density and high purity. You can.

In addition, the method for manufacturing a gallium-containing thin film of the present invention has excellent thermal stability and durability by manufacturing a gallium-containing thin film using a gallium compound having high thermal stability and reactivity as a precursor, or using the composition for depositing a gallium-containing thin film. It is possible to produce high-quality gallium-containing thin films.

Figure 1 - TGA analysis results of gallium compound 1 prepared in Example 1
Figure 2 - DSC analysis results of gallium compound 1 prepared in Example 1
Figure 3 - Growth rate per cycle of gallium-containing thin films as a function of injection time of gallium compound 1.

Hereinafter, the present invention will be described in more detail. Unless otherwise defined, the technical and scientific terms used herein have meanings commonly understood by those skilled in the art to which this invention pertains, and the following description will not unnecessarily obscure the gist of the present invention. Descriptions of possible notification functions and configurations are omitted.

As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly dictates otherwise.

As used herein, “comprises” is an open description that has the equivalent meaning to expressions such as “comprises,” “contains,” “has,” or “characterized by” elements that are not additionally listed; Does not exclude materials or processes.

As used herein, the term “gallium compound” has an equivalent meaning to expressions such as “gallium precursor” or “gallium precursor compound.”

As used herein, the term “thermal stability” may mean that physical properties do not change even during a continuous heating process or a high temperature process, and specifically means that no structural change occurs even when exposed to the harsh conditions described above for a long period of time. .

As used herein, “alkyl” means a saturated straight-chain or branched non-cyclic hydrocarbon having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms. “Lower alkyl” means straight-chain or branched alkyl having 1 to 4 carbon atoms. Representative saturated straight-chain alkyls include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl and n-decyl, while saturated branched alkyls include Alkyl is isopropyl, sec-butyl, isobutyl, tert-butyl, isopentyl, 2-methylhexyl, 3-methylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-methylhexyl, 3 -Methylhexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2,3-dimethylbutyl, 2,3- Dimethylpentyl, 2,4-dimethylpentyl, 2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl, 2,2-dimethylpentyl, 2,2-dimethylhexyl, 3,3-dimethyl Pentyl, 3,3-dimethylhexyl, 4,4-dimethylhexyl, 2-ethylpentyl, 3-ethylpentyl, 2-dethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-methyl-2-ethylpentyl, 2-methyl-3-ethylpentyl, 2-methyl-4-ethylpentyl, 2-methyl-2-ethylhexyl, 2-methyl-3-ethylhexyl, 2-methyl-4-ethylhexyl, 2,2-di Includes ethylpentyl, 3,3-diethylhexyl, 2,2-diethylhexyl, and 3,3-diethylhexyl.

When written as “C1-C10” in this specification, it means that the number of carbon atoms is 1 to 10. For example, C1-C4alkyl means alkyl having 1 to 4 carbon atoms. Specific examples may be methyl, ethyl, propyl, isopropyl, butyl, isobutyl, or tert-butyl. .

One aspect of the present invention is a gallium-containing gallium compound including a gallium compound represented by the following formula (1), which has excellent reactivity and thermal stability and is easy to handle as it exists as a solid or liquid at room temperature, making it very useful as a precursor for gallium-containing thin films. A composition for thin film deposition is provided.

[Formula 1]

In Formula 1,

R ¹ and R ² are independently C1-C10 alkyl, C3-C10 cycloalkyl, or -NR ^a R ^b ;

R ^a and R ^b are independently C1-C10 alkyl or C3-C10 cycloalkyl;

R ³ and R ⁴ are independently C1-C10 alkyl or C3-C10 cycloalkyl.

The gallium compound of the present invention has at least one amino ligand (-NR ³ R ⁴ , where R ³ and R ⁴ are independently C1-C10 alkyl or C3-C10 cycloalkyl) bonded to the central metal gallium (Ga). With this structure, thermal stability and reactivity are significantly improved due to the introduction of a specific ligand, while high volatility allows the production of high-quality thin films.

In addition, since the gallium compound of the present invention exists in solid or liquid form at room temperature and pressure, it has high storage stability and excellent volatility, so it can be used as a precursor for deposition of gallium-containing thin films to produce high-density, high-purity gallium-containing thin films. .

In atomic layer deposition (ALD), the reactants must be highly volatile, the material must be stable, and the reactivity must be high. Accordingly, most semiconductor manufacturers (chip makers) prefer liquid precursors due to their advantages in the process. However, despite these advantages, solid precursors are still used because they are cheaper than liquid precursors and have fewer disadvantages than liquid precursors, such as unreliability due to severe contamination of thin films due to unstable decomposition or low reactivity during the process. am.

In Formula 1 according to one embodiment, R ¹ and R ² are independently C1-C10 alkyl or -NR ^a R ^b ; R ^a and R ^b are independently C1-C10 alkyl; R ³ and R ⁴ may be independently C1-C10 alkyl.

In Formula 1 according to one embodiment, R ¹ and R ² are independently C1-C6 alkyl or -NR ^a R ^b ; R ^a and R ^b are independently C1-C6alkyl; R ³ and R ⁴ may be independently C1-C6 alkyl.

In Formula 1 according to one embodiment, R ¹ and R ² are independently C1-C4 alkyl or -NR ^a R ^b ; R ^a and R ^b are independently C1-C4alkyl; R ³ and R ⁴ may be independently C1-C4 alkyl.

In Formula 1 according to one embodiment, R ¹ and R ² are the same as each other and are C1-C4 alkyl or -NR ^a R ^b ; R ^a and R ^b are independently C1-C4alkyl; R ³ and R ⁴ may be independently C1-C4 alkyl.

In one embodiment, R ¹ and R ² are the same as each other and may be methyl or ethyl.

In one embodiment, R ¹ and R ² are the same as each other and are -NR ^a R ^b ; R ^a and R ^b may independently be methyl, ethyl, isopropyl or t-butyl.

In Formula 1 according to one embodiment, R ¹ is C1-C4 alkyl; R ² is -NR ^a R ^b ; R ^a and R ^b are independently C1-C4alkyl; R ³ and R ⁴ may be independently C1-C4 alkyl.

In one embodiment, R ¹ is methyl or ethyl; R ² is -NR ^a R ^b ; R ^a , R ^b , R ³ and R ⁴ may independently be methyl, ethyl, isopropyl or t-butyl.

Preferably, in one embodiment, the gallium compound may be represented by the following Chemical Formula 1-1, Chemical Formula 1-2, or Chemical Formula 1-3.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

In Formulas 1-1 to 1-3,

R' and R'' are each independently C1-C4alkyl;

R ³ to R ⁸ are independently C1-C4 alkyl.

In one embodiment, in Formula 1-1, R' is methyl or ethyl; R ³ and R ⁴ may independently be methyl, ethyl, isopropyl or t-butyl.

In one embodiment, in Formula 1-2, R ³ to R ⁸ may independently be methyl, ethyl, isopropyl, or t-butyl.

In one embodiment, in Formula 1-2, R ³ , R ⁵ and R ⁷ are the same as each other and are methyl, ethyl, isopropyl or t-butyl; R ⁴ , R ⁶ and R ⁸ are the same as each other and may be methyl, ethyl, isopropyl or t-butyl.

In one embodiment, in Formula 1-3, R'' is methyl or ethyl; R ³ to R ⁶ may independently be methyl, ethyl, isopropyl, or t-butyl.

Specifically, the gallium compound according to one embodiment may be selected from the following compounds, but is not limited thereto.

The composition for thin film deposition according to one embodiment may be specifically for indium gallium zinc oxide (IGZO) thin film deposition.

In addition to the gallium compounds described above, it may further include an indium precursor and a zinc precursor.

The indium precursor may be C1-C6 alkyl indium, and the zinc precursor may be C1-C6 alkyl zinc. Specifically, the indium precursor may be trimethylindium (TMI) or dimethylaminopropyldimethylindium (3-(Dimethylamino)propryl). (dimethyl)indium; DADI), and the zinc precursor may be diethylzinc (DEZ), but is not limited thereto.

The molar ratio of the indium precursor: gallium precursor: zinc precursor may be 1 to 10:1 to 10:1 to 10, specifically 1 to 5:1 to 5:1 to 5, more specifically 1:1:1. You can.

Another aspect of the present invention provides a method of forming a gallium-containing thin film using a gallium compound represented by Formula 1 according to an embodiment.

The method of manufacturing the gallium-containing thin film is a common method used in the industry, specifically atomic layer deposition (ALD), chemical vapor deposition (CVD), metal organic chemical vapor deposition (MOCVD), and low pressure chemical vapor deposition (LPCVD). , it may be plasma-enhanced chemical vapor deposition (PECVD) or plasma-enhanced atomic layer deposition (PEALD).

More preferably, the method for manufacturing the indium-containing thin film according to an embodiment may be atomic layer deposition (ALD), chemical vapor deposition (CVD), or metal organic chemical vapor deposition (MOCVD).

A gallium-containing thin film according to an embodiment may be manufactured by a common method used in the art, for example, metal organic chemical vapor deposition (MOCVD), atomic layer deposition (ALD), low pressure vapor deposition (LPCVD), and plasma enhanced Examples include vapor deposition (PECVD) or plasma enhanced atomic layer deposition (PEALD), but atomic layer deposition (ALD) or plasma enhanced atomic layer deposition (PEALD) is preferred.

In one embodiment, the gallium-containing thin film of the present invention may be manufactured by atomic layer deposition (ALD).

A method of manufacturing a gallium-containing thin film according to an embodiment includes forming a thin film by depositing the gallium compound on a substrate, and specifically, a) adsorbing the gallium compound on the substrate; b) purging non-adsorbed gallium compounds; c) forming a gallium-containing thin film by injecting a reaction gas; and d) purging residual reaction gas and reaction by-products.

A method of manufacturing a gallium-containing thin film according to an embodiment may include forming a single-layer or multi-layer thin film by depositing the gallium compound and at least one selected from an indium precursor and a zinc precursor on a substrate, wherein the gallium compound, The indium precursor and the zinc precursor can be deposited on the substrate simultaneously, or the gallium compound, the indium precursor, and the zinc precursor can be mixed and deposited on the substrate to form a thin film with a single-layer structure, and the indium precursor, the gallium compound, and the zinc precursor can be deposited on the substrate. may be sequentially deposited on a substrate to form a thin film with a multilayer structure. Specifically, the indium precursor may be trimethylindium (TMI), and the zinc precursor may be diethylzinc (DEZ), but are not limited thereto. The multilayer thin film may be an indium-gallium-zinc oxide film (IGZO thin film), and the composition ratio of indium:gallium:zinc may be 1 to 10:1 to 10:1 to 10, specifically 1 to 5:1. to 5:1 to 5, more specifically 1:1:1.

The gallium-containing thin film according to one embodiment is manufactured using the gallium compound, and is not limited, but is preferably a gallium nitride film, a gallium oxide film, or an indium-gallium-zinc oxide film, and is preferably a gallium oxide film or an indium-gallium-zinc oxide film. It may be a zinc oxide film.

The method for producing a gallium-containing thin film of the present invention uses the gallium compound of the present invention, which has high volatility and thermal stability, as a precursor, and the produced gallium-containing thin film has extremely excellent physical, electrical, and chemical properties.

In the method for manufacturing a gallium-containing thin film according to an embodiment, the injection temperature of the gallium compound of the present invention may be room temperature (25°C to 120°C, and due to the high volatility of the gallium compound of the present invention, the temperature of the substrate on which the gallium compound will be deposited is 100 to 450°C, and the pressure inside the chamber may be 0.1 to 10 torr.

The reaction gas used in the method for manufacturing a gallium-containing thin film according to an embodiment is not limited, but includes hydrogen (H ₂ ), hydrazine (N ₂ H ₄ ), dimethylhydrazine (Me ₂ N ₂ H ₂ ), and ozone ( O ₃ ), oxygen (O ₂ ), water (H ₂ O), ammonia (NH ₃ ), nitrogen (N ₂ ), silane (SiH ₄ ), borane (BH ₃ ), diborane (B ₂ H ₆ ), and One or more mixed gases selected from phosphine (PH ₃ ) can be used, and the reaction gas is not limited, but can be supplied at a flow rate of 10 to 10,000 sccm, specifically 50 to 1,000 sccm. It can be.

Specifically, when deposition is performed in the presence of oxidizing reaction gases such as water vapor (H ₂ O), oxygen (O ₂ ), or ozone (O ₃ ), a gallium oxide film may be formed, and ammonia (NH ₃ ) or hydrazine (N ₂ H ₄ ) If deposition is performed in the presence of a nitrogen-containing reaction gas such as, a gallium nitride film may be formed.

The purge gas is an inert gas, but is not limited thereto, and may be one or a mixture of two or more gases selected from argon (Ar) and helium (He).

The substrate used in the method of manufacturing a gallium-containing thin film according to an embodiment includes a substrate containing one or more semiconductor materials selected from the group consisting of Si, SiO2, Pt, TiN, Ge, SiGe, GaP, GaAs, SiC, SiGeC, InAs, and InP; SOI (Silicon On Insulator) substrate; Quartz substrate; or a glass substrate for display; Polyimide, PolyEthylene Terephthalate (PET), PolyEthylene Naphthalate (PEN), Poly Methyl MethAcrylate (PMMA), Polycarbonate (PC, PolyCarbonate), Polyether Sulfone Flexible plastic substrates such as (PES) and polyester; It may be, but is not limited to this.

The method for manufacturing a gallium-containing thin film according to an embodiment has high volatility and high thermal stability, and by using it as a precursor for thin film deposition, the gallium-containing thin film has excellent physical, electrical and chemical properties, and is high-density and high-purity, high-quality, uniform gallium-containing thin film. can be formed.

Another aspect of the present invention is to provide a gallium compound that can be very useful as a precursor for gallium-containing thin films. The gallium compound of the present invention is represented by the following formula (2).

[Formula 2]

In Formula 2,

R ¹¹ to R ¹⁶ are independently C1-C10 alkyl or C3-C10 cycloalkyl.

In Formula 2 according to one embodiment, R ¹¹ to R ¹⁶ may independently be C1-C10 alkyl.

In Formula 2 according to one embodiment, R ¹¹ to R ¹⁶ may independently be C1-C6 alkyl.

In Formula 2 according to one embodiment, R ¹¹ to R ¹⁶ may independently be C1-C4 alkyl.

In one embodiment, R ¹¹ to R ¹⁶ may independently be methyl, ethyl, isopropyl, or t-butyl.

In Formula 2 according to one embodiment, R ¹¹ , R ¹³ and R ¹⁵ are the same and are C1-C4 alkyl; R ¹² , R ¹⁴ and R ¹⁶ are the same as each other and may be C1-C4 alkyl.

In one embodiment, R ¹¹ , R ¹³ and R ¹⁵ are the same as each other and are methyl, ethyl, isopropyl or t-butyl; R ¹² , R ¹⁴ and R ¹⁶ are the same as each other and may be methyl, ethyl, isopropyl or t-butyl.

Specifically, the gallium compound according to one embodiment may be selected from the following compounds, but is not limited thereto.

The gallium compound of the present invention contains three amino ligands (-NR ¹¹ R ¹² , -NR ¹³ R ¹⁴ , -NR ¹⁵ R ¹⁶ ) on gallium (Ga), a central metal, where R ¹¹ to R ¹⁶ are independently C1-C10. alkyl or C3-C10 cycloalkyl) is combined, and has the advantage of controlling reactivity by adjusting the symmetry and asymmetry of the compound depending on the substituent, and the introduction of three amino ligands results in remarkable thermal stability and reactivity. At the same time, high volatility is improved, allowing the production of high-quality thin films.

In addition, since the gallium compound of the present invention exists in solid or liquid form at room temperature and pressure, it has high storage stability and excellent volatility, so it can be used as a precursor for deposition of gallium-containing thin films to produce high-density, high-purity gallium-containing thin films. .

Hereinafter, the configuration of the present invention will be described in more detail through examples. However, the following examples are intended to aid understanding of the present invention, and the scope of the present invention is not limited thereto.

Hereinafter, the synthesis of the gallium compound according to the present invention was performed using a standard Schlenk flask or purge box under an inert argon or nitrogen atmosphere, except where otherwise noted. The structure of the obtained gallium compound was analyzed through ^1H NMR spectrum and elemental analysis. In addition, the thickness of the deposited gallium-containing thin film was measured using an ellipsometer (Ellipsometer, Thermowave, Optiprobe 2600) and X-ray photoelectron spectroscopy (XPS, X-ray Photoelectron Spectroscopy, ThermoFisher Scientific, K-Alpha+). The composition of the thin film was analyzed.

[Example 1] Synthesis of gallium compound 1

A 500ml Schlenk flask and two 250ml Schlenk flasks dried in an oven were placed in a purge box and purged for more than 30 minutes to remove as much moisture inside the glassware as possible.

In the purge box, 15g (0.1479mol) of diisopropyl amine was added to a 500ml Schlenk flask (A), and 59.15ml (0.1479mol) of n-butyl lithium 2.5M in hexane was added to a 250ml Schlenk flask (B). Each flask was then moved to the hood. Flask A was cooled to 0°C using an acetone/dry ice bath, and 200ml of hexane was added while blowing nitrogen. The solution from flask B was pressurized and transferred to flask A, which was maintained within 10°C. At this time, it was added slowly while checking the thermometer, and the temperature was maintained below 10°C. After completion of pressurized transfer, 30ml of hexane was added to flask B, washed, and further pressurized transferred to flask A twice. The reaction was carried out at room temperature until the NH peak of diisopropyl amine disappeared through NMR measurement to lithium diisopropyl amine.

Next, 20 g (0.1479 mol) of dimethylgallium chloride was added to a 250 ml Schlenk flask in the purge box (C), moved to a hood, and then 100 ml of hexane was added and dissolved. The temperature of flask A containing the intermediate was cooled back to 0°C using an acetone/dry ice bath, and then the solution from flask C was transferred under pressure to flask A at the same temperature. At this time, I added it slowly while checking the thermometer. Afterwards, the reaction proceeded at room temperature for 18 hours. When the reaction was completed, the salt was removed by filtration, and the remaining solvent was removed through vacuum drying to obtain a solid product. The obtained solid product was purified by sublimation at 45°C under a pressure of 197 mtorr (equivalent temperature 237°C) to obtain the title gallium compound 1 as a white solid (20.1 g, yield 68%).

^1H NMR 400MHz (C ₆ D ₆ ): δ 0.0205 (s, 6H), 1.1620 (d, 12H), 3.5452 (q, 2H)

[Example 2] Synthesis of gallium compound 2

A 1000ml Schlenk flask and two 500ml Schlenk flasks dried in an oven were placed in a purge box and purged for more than 30 minutes to remove as much moisture inside the glassware as possible.

In the purge box, 20.5 g (0.35 mol) of N -ethylmethyl amine was added to a 500 ml Schlenk flask (A), and 139.2 ml (0.35 mol) of n -butyl lithium 23% in hexane was added to a 250 ml Schlenk flask (B). . Each flask was then moved to the hood. Flask A was cooled to 0°C using an acetone/dry ice bath, and 240ml of hexane was added while blowing nitrogen. The solution from flask B was pressurized and transferred to flask A, which was maintained within 10°C. At this time, it was added slowly while checking the thermometer, and the temperature was maintained below 10°C. After completion of pressurized transfer, 30ml of hexane was added to flask B, washed, and further pressurized transferred to flask A twice. N -ethylmethyl amine was lithiated by carrying out the reaction at room temperature until the NH peak of N -ethylmethyl amine disappeared through NMR measurement.

Next, 20 g (0.11 mol) of gallium trichloride was added to a 500 ml Schlenk flask in the purge box (C), it was moved to a hood, and then 300 ml of hexane was added and dissolved. The temperature of flask A containing the intermediate was cooled back to 0°C using an acetone/dry ice bath, and then the solution from flask C was transferred under pressure to flask A at the same temperature. At this time, I added it slowly while checking the thermometer. Afterwards, the reaction proceeded at room temperature for 18 hours. When the reaction was completed, the salt was removed by filtration, and the remaining solvent was removed through vacuum drying to obtain the product, gallium compound 2 (15.8 g, yield 69%).

[Experimental Example 1] Material analysis of gallium compounds

To measure the thermal stability and decomposition temperature of gallium compound 1 prepared in Example 1, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used (measurement conditions: 10 Kmin ^-1 under a nitrogen atmosphere, 500 temperature rise to ℃).

Graphs of the TGA and DSC analysis results are shown in Figures 1 and 2, respectively.

From Figure 1, it can be seen that gallium compound 1 prepared in Example 1 shows a mass reduction of about 50% at 155.5°C. Additionally, it was confirmed from Figure 2 that it can be thermally stable at a temperature of 146.6°C or lower. From this, it can be seen that the gallium compound of the present invention has excellent thermal stability.

[Examples 3 to 7] Preparation of gallium-containing thin films

Gallium Compound 1 prepared in Example 1 was used as a precursor for deposition of gallium-containing thin films, ozone (O ₃ ) was used as a reaction gas, the concentration of ozone was 220 g/㎥, and argon ( A gallium-containing thin film was formed by atomic layer deposition (ALD) using Ar).

A silicon oxide film was used as a substrate. A silicon oxide film substrate was loaded into the deposition chamber, and the substrate temperature was set to 250°C. In order to appropriately maintain the vapor pressure of the gallium compound and prevent condensation, gallium compound 1 was placed in a stainless steel bubbler and maintained at 30°C. The flow rate of ozone (O ₃ ), a reaction gas, was fixed at 1000 sccm, the flow rate of carrier gas (Ar) was fixed at 300 sccm, the flow rate of purge gas (Ar) was fixed at 2000 sccm, and the process pressure was 1 Torr. It was maintained as . Thin film deposition using a gallium precursor was performed by repeating 100 cycles of four sequential steps: gallium precursor injection - purge (Ar) - ozone (O ₃ ) injection - purge (Ar) to deposit a gallium-containing thin film. Table 1 below shows detailed deposition conditions and results.

Example 3 4 5 6 7 Process pressure (Torr) One One One One One Silicon substrate temperature (℃) 250 250 250 250 250 gallium
precursor Heating temperature (℃) 30 30 30 30 30 Injection time (seconds) One 3 5 10 20 Fudge
(Ar) Flow rate (sccm) 2000 2000 2000 2000 2000 time (seconds) 20 20 20 20 20 Ozone (O ₃ ) Flow rate (sccm) 1000 1000 1000 1000 1000 time (seconds) 20 20 20 20 20 Fudge
(Ar) Flow rate (sccm) 2000 2000 2000 2000 2000 time (seconds) 20 20 20 20 20 Number of depositions to give 100 100 100 100 100 Thin film thickness (Å) 28.7 33.2 34.7 34.6 37.4 GPC (Å) 0.29 0.33 0.35 0.35 0.37

The growth rate per cycle (GPC) according to the injection time of gallium compound 1 was measured and shown in FIG. 3. From Table 1 and Figure 3, the GPC of the gallium precursor according to the present invention increases from 1 to 4 seconds of injection time, and the GPC is maintained at a constant level from 4 seconds of injection time, resulting in saturation from 3 seconds of injection time of the gallium precursor. It was confirmed that the growth rate of the gallium-containing thin film was constant.

The gallium compound according to the present invention has excellent thermal stability and volatility and is useful as a precursor for gallium-containing thin films. It has a high vapor pressure, enabling uniform thin film deposition through uniform composition control through uniform precursor supply during thin film production. High-density and high-purity gallium-containing thin films can be easily manufactured.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

Claims (13)

A composition for deposition of a gallium-containing thin film comprising a gallium compound represented by the following formula (1):
[Formula 1]

In Formula 1,
R ¹ and R ² are independently C1-C10 alkyl, C3-C10 cycloalkyl, or -NR ^a R ^b ;
R ^a and R ^b are independently C1-C10 alkyl or C3-C10 cycloalkyl;
R ³ and R ⁴ are independently C1-C10 alkyl or C3-C10 cycloalkyl. According to clause 1,
R ¹ and R ² are independently C1-C10 alkyl or -NR ^a R ^b ; R ^a and R ^b are independently C1-C10 alkyl; R ³ and R ⁴ are each independently C1-C10 alkyl, a gallium-containing composition for thin film deposition. According to clause 1,
R ¹ and R ² are the same as each other and are C1-C4 alkyl or -NR ^a R ^b ; R ^a and R ^b are independently C1-C4alkyl; R ³ and R ⁴ are each independently C1-C4 alkyl, a gallium-containing composition for thin film deposition. According to clause 1,
A composition for depositing a gallium-containing thin film, wherein the gallium compound is selected from the following compounds.
A method of forming a gallium-containing thin film using the composition for depositing a gallium-containing thin film according to any one of claims 1 to 4. A method of producing a gallium-containing thin film, comprising forming a thin film by depositing a gallium compound represented by the following formula (1) on a substrate.
[Formula 1]

In Formula 1,
R ¹ and R ² are independently C1-C10 alkyl, C3-C10 cycloalkyl, or -NR ^a R ^b ;
R ^a and R ^b are independently C1-C10 alkyl or C3-C10 cycloalkyl;
R ³ and R ⁴ are independently C1-C10 alkyl or C3-C10 cycloalkyl. According to clause 6,
The method of manufacturing a gallium-containing thin film includes forming a thin film by depositing the gallium compound and at least one selected from an indium precursor and a zinc precursor on a substrate. According to clause 6,
A method of producing a gallium-containing thin film, wherein the deposition is performed by chemical vapor deposition (CVD) or atomic layer deposition (ALD). According to clause 6,
The gallium-containing thin film is a gallium oxide thin film, a gallium thin film, a gallium nitride thin film, or an indium gallium zinc oxide (IGZO) thin film. A gallium compound represented by the following formula (2):
[Formula 2]

In Formula 2,
R ¹¹ to R ¹⁶ are independently C1-C10 alkyl or C3-C10 cycloalkyl. According to clause 10,
The gallium compound wherein R ¹¹ to R ¹⁶ are independently C1-C10 alkyl. According to clause 10,
R ¹¹ , R ¹³ and R ¹⁵ are the same and are C1-C4 alkyl; R ¹² , R ¹⁴ and R ¹⁶ are the same as each other and are C1-C4 alkyl, a gallium compound. According to clause 10,
The gallium compound is selected from the following compounds.