JP7232307B2 - Rare earth precursor, method for producing same, and method for forming thin film using same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vapor deposition compound capable of thin film deposition through vapor deposition, and more specifically, an atomic layer deposition (ALD) method or a chemical vapor deposition method (ALD). The present invention relates to a rare earth precursor which has excellent volatility and thermal stability applicable to deposition, CVD) and has excellent reactivity with reaction gases, a method for producing the same, and a method for forming a thin film using the same.

Silicon oxide (SiO ₂ ), which has been used as a dielectric for several decades, has recently become a "metal gate/high-k" material due to the dense packing and shrinking channel lengths of semiconductor devices. )” transistor.

In particular, there is a need for new gate dielectric materials for memory elements and capacitors in Dynamic Random Access Memories (DRAMs).

As device sizes approach the 20 nm level, there is an increasing demand for high dielectric constant materials and processes.

Preferably, the high-k material should have high bandgap and band-offset, high k value, excellent stability on silicon, minimal SiO ₂ interfacial layer and high quality interface on the substrate. must. Amorphous or highly crystalline temperature films are also preferred.

Hafnium oxide (HfO ₂ ) is a representative high-k material that is being actively studied and applied to replace silicon oxide. It has been demanded.

Rare-earth-doped hafnium oxide and the like are listed as strong candidates for next-generation high-k materials.

In particular, rare-earth-containing materials are promising high-k dielectric materials for advanced silicon CMOS, germanium CMOS and III-V transistor devices, and a new generation of oxides based on them is a common dielectric It is reported to offer considerable capacity advantages over materials.

In addition, materials containing rare earth elements are expected to be applied to the production of perovskite materials having properties such as ferroelectricity, pyroelectricity, piezoelectricity, and resistance conversion. In other words, _ABO3 -type perovskite is produced through a vapor deposition process using an organometallic compound precursor, and the type and composition of A, B, and cations (rare earth or transition metal) are adjusted to improve the dielectric properties and electronic conductivity of the material. And various properties such as oxygen ion conductivity are imparted, and research is progressing for use in various industrial fields such as fuel cells, sensors, and secondary batteries.

In addition, rare earth element-containing materials are being actively researched for use in encapsulation materials and next-generation non-volatile memories that utilize the excellent water permeation resistance of multi-layered oxide thin film structures.

However, since the deposition of rare earth-containing layers is still difficult, new materials and processes are continuously sought. In this regard, rare earth precursors with various ligands have been investigated.

Representative examples of ligands constituting rare earth precursors include compounds such as amides, amidinates, beta-diketonates, and cyclopentadienyls (Cp). However, these precursors have drawbacks such as high melting points, low deposition temperatures, high impurities in thin films, and relatively low reactivity, which make them difficult to apply to practical processes.

Specifically, lanthanum-2,2,6,6-tetramethylheptanedionate ([La(tmhd) ₃ ]) has a high melting point of 260° C. or higher, and rare earth-2,2,7-trimethyl The melting point of octanedionate ([La(tmod) ₃ ]) is 197°C. Also, the transfer efficiency of beta-diketonates is very difficult to control, the thin film growth rate is low, and the carbon impurity production rate is high, resulting in low film purity.

Cyclopentadienyl (Cp) compounds can be realized as some liquid compounds, but have the disadvantage of high content of carbon impurities in the thin film in process evaluation.

Molecular design can help improve volatility and lower melting points, but has been found to have limited application at process conditions. For example, La(iPrCp) ₃ (where iPr is isopropyl) is not suitable for ALD processes above 225°C.

The amide ligand RE(NR ₂ ) ₃ (RE is a rare earth element) is not suitable for ALD and CVD processes due to the structural instability of the compound.

In addition, some of the currently available rare earth-containing precursors have many problems when used in deposition processes. For example, fluorinated rare earth precursors may produce REF ₃ (where RE is a rare earth element) as a by-product. This by-product is known to be difficult to remove.

That is, conventional rare earth precursors are not thermally stable at high temperatures, resulting in low deposition rates during chemical vapor deposition (CVD) and atomic layer deposition (ALD) processes. It had its shortcomings.

As a result, the development of alternative precursors for the deposition of rare earth-containing films is a desirable practice.

Korea Registered Patent No. 10-2138707

DISCLOSURE OF THE INVENTION The present invention is intended to solve the problems of the existing rare earth precursors mentioned above, and provides a deposition material having excellent thermal stability and volatility, and excellent reactivity with reaction gases. The aim is to provide rare earth precursor compounds.

In addition, the present invention intends to provide a thin film manufacturing method using the rare earth precursor compound.

However, the problems to be solved by the present application are not limited to the problems mentioned above, and other problems not mentioned should be clearly understood by those skilled in the art from the following description.

In order to solve the problems of the rare earth precursors as described above, studies on various ligands have been conducted. Still had the same problem. In addition, the heteroleptic compounds that have appeared since then have the advantage of thermal stability and volatility, but have the disadvantage of low reactivity with reaction gases.

Therefore, in order to solve such problems, the present inventors have developed heteroleptic compounds that can maintain the existing advantages of heteroleptic compounds and compensate for the drawback of low reactivity with reaction gases. A rare earth precursor was synthesized.

In particular, rare earth precursors containing any one ligand selected from the group consisting of alkoxide, amide and akyl and a neutral ligand were synthesized.

Through this, it is possible to obtain a rare earth precursor that has excellent volatility and thermal stability and high reactivity with a reaction gas as compared to existing known rare earth precursor compounds.

One aspect of the present application provides a compound represented by Formula 1 below:

In the chemical formula 1,
M is a rare earth element,
R ₁ to R ₆ are each independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
R ₇ to R ₉ are each independently a linear or branched alkyl group having 1 to 5 carbon atoms; —OR ₁₀ ; or —N(R ₁₁ ) ₂ ;
each R ₁₀ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
each R ₁₁ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms; or Si(R ₁₂ ) ₃ ;
Each R ₁₂ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms.

Another aspect of the present application provides vapor deposition precursors comprising the compounds.

Another aspect of the present application provides a method of making a thin film, comprising introducing the vapor deposition precursor into a chamber.

The novel vapor-deposited rare earth compounds according to the present invention and precursors containing said vapor-deposited compounds have excellent thermal stability and volatility. It also has excellent reactivity with reaction gases.

The vapor deposition precursor of the present invention enables uniform thin film deposition, thereby ensuring excellent thin film physical properties, thickness and step coverage.

The physical properties described above provide precursors suitable for atomic layer deposition and chemical vapor deposition and contribute to excellent thin film properties.

Example 1 ((Me, Me—NHC)La[N(SiMe ₃ ) ₂ ] ₃ ), Example 2 ((Et, Me—NHC)La[N(SiMe ₃ ) ₂ ] ₃ ) and Examples of the present application 4 is a graph of the results of differential scanning calorimetry (DSC) analysis of a compound of 4(( ⁱ Pr, Me-NHC)La[N(SiMe ₃ ) ₂ ] ₃ ). 1 is a graph of thermogravimetric (TG) analysis results of compounds of Examples 1 to 5 of the present application (Example 1: (Me, Me—NHC)La[N(SiMe ₃ ) ₂ ] ₃ , Example 2: (Et, Me—NHC)La[N(SiMe ₃ ) ₂ ] ₃ , Example 3: (Et, Me—NHC)Y[N(SiMe ₃ ) ₂ ] ₃ , Example 4: ( ⁱ Pr, Me—NHC)La[N(SiMe ₃ ) ₂ ] ₃ , Example 5: ( ⁱ Pr, Me, Me, Me—NHC)La[N(SiMe ₃ ) ₂ ] ₃ ). 1 is a graph of thermogravimetric (TG) analysis results of compounds of Examples 7 and 9 of the present application (Example 7: (Et, Me—NHC)La(O ^t Bu) ₃ , Example 9: ( ⁱ Pr,Me-NHC)La(O ^t Bu) ₃ ).

Hereinafter, embodiments and embodiments of the present application will be described in detail so that those skilled in the art can easily implement the present invention. This application may, however, be embodied in many different forms and is not limited to the implementations and examples set forth herein.

Embodiments and examples of the present application will be described in detail below. However, the present application is not limited to such implementations and examples and drawings.

One aspect of the present application provides a compound represented by Chemical Formula 1 below.

In the chemical formula 1,
M is a rare earth element,
R ₁ to R ₆ are each independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
R ₇ to R ₉ are each independently a linear or branched alkyl group having 1 to 5 carbon atoms; —OR ₁₀ ; or —N(R ₁₁ ) ₂ ;
each R ₁₀ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
each R ₁₁ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms; or Si(R ₁₂ ) ₃ ;
Each R ₁₂ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms.

That is, the compounds of the present invention are heteroleptic compounds containing two or more ligand types, not all ligand types being the same, and the neutral ligand is N-heterocyclic carbene. contains.

The compounds of the present invention also contain any one ligand selected from the group consisting of alkoxides, amides and akyls.

The N-heterocyclic carbene improves the thermal stability of the compound, and any one ligand selected from the group consisting of alkoxides, amides and akyls enhances the volatilization of the compound. It enhances the reactivity with reaction gas at the same time as improving the property.

In one embodiment of the present application, preferably R ₁ to R ₆ and R ₁₀ to R ₁₂ are each independently hydrogen, methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group , an iso-butyl group, a sec-butyl group and a tert-butyl group, but is not limited thereto.

は、下記化学式１ａ～１ｊで表されるリガンドからなる群より選択されるいずれか一つであってもよい。

In one embodiment of the present application, preferably, the formula 1

may be any one selected from the group consisting of ligands represented by the following chemical formulas 1a to 1j.

In one embodiment of the present application, the compound may be any one compound selected from the group consisting of compounds represented by the following chemical formulas 1-1 to 1-7.

In the chemical formulas 1-1 to 1-7,
M is a rare earth element,
^t Bu is tert-butyl.

In one embodiment of the present application, the rare earth elements include Sc (scandium), Y (yttrium), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu ), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu) good.

Another aspect of the present application provides a vapor deposition precursor, preferably a vapor deposition precursor, comprising said compound.

Another aspect of the present application provides a method of making a thin film comprising introducing the vapor deposition precursor into a chamber. Introducing the vapor deposition precursor into the chamber may comprise physisorption, chemisorption, or physical and chemisorption.

In one embodiment of the present application, the method for manufacturing the thin film may include atomic layer deposition (ALD) or chemical vapor deposition (CVD). Deposition can be Metal Organic Chemical Vapor Deposition (MOCVD), Low Pressure Chemical Vapor Deposition (LPCVD), Pulsed Chemical Vapor Deposition (P-CVD), Plasma Enhanced Atomic It may include, but is not limited to, layer deposition techniques (PE-ALD), or combinations thereof.

In one embodiment of the present application, the method for manufacturing a thin film includes the step of injecting at least one of hydrogen ( _H2 ), an oxygen (O) atom-containing compound, and a nitrogen (N) atom-containing compound as a reaction gas. It may contain further.

If the desired rare earth-containing film contains oxygen, the reactive gas may be oxygen ( _O2 ), ozone ( _O3 ), water ( _H2O ), hydrogen peroxide ( _{H2O2 )} , and any combination thereof. More may be selected, but it is not limited to this.

If the desired rare earth-containing film contains nitrogen, the reactant gas may be selected from nitrogen ( _N2 ), ammonia ( _NH3 ), hydrazine ( _N2H4 ) and any combination _thereof , It is not limited to this.

Desirable rare earth-containing films may also contain other metals.

Hereinafter, the present invention will be specifically described by using Synthesis Examples, Examples, Experimental Examples and Production Examples, but the present application is not limited thereto.

<Synthesis Example 1> Synthesis of (NHC)La[N(SiMe ₃ ) ₂ ] ₃ 0.03 mol of 3-R2-4-R3-5-R4-imidazolium chloride or bromide) is weighed into a flask and dissolved in 200 mL of tetrahydrofuran (THF). 22 g (0.12 mol) of sodium bistrimethylsilylamide (Sodiumbis(trimethylsilyl)amide) dissolved in THF are slowly added to this solution at 0°C. Then, the mixture is stirred at room temperature for about 16 hours to complete the reaction, and the solvent and volatile by-reactants are removed under vacuum. The residue is diluted with hexane, filtered through a filter containing celite, and the filtrate is dried again under vacuum. This solid was dissolved again in hexane and recrystallized at -40°C to give a colorless or white crystalline solid.

The reaction of Synthesis Example 1 is shown in Reaction Formula 1 below.

HMDS in Reaction Formula 1 is hexamethyldisilazane.

<Synthesis Example 2> Synthesis of (NHC)La(O ^t Bu)3 (NHC)La[N( _SiMe3 ) ₂ ] ₃ (0.0045 mol) synthesized in Synthesis Example 1 was dissolved in 50 mL of toluene. , 1.28 mL (0.0135 mol) of tertiary butyl alcohol diluted in toluene are slowly added at 0°C. Then, the mixture is stirred at room temperature for about 16 hours to complete the reaction, and the solvent and volatile by-reactants are removed under vacuum. The residue is diluted with hexane, filtered through a filter containing celite, and the filtrate is dried again under vacuum. This solid was dissolved again in hexane and recrystallized at -40°C to obtain an orange solid.

The reaction of Synthesis Example 2 is shown by the following reaction chemical formula (2).

^t Bu in the reaction formula (2) is tert-butyl, and HMDS is hexamethyldisilizane.

<Example 1> Synthesis of (Me, Me-NHC)La[N(SiMe ₃ ) ₂ ] ₃ Synthesized according to Synthesis Example 1, wherein R ₁ and R ₂ are each methyl, R ₃ and R ₄ are each hydrogen, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 3-1 below.

The synthesized compound is a colorless crystalline solid, the yield is 70.51%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ 0.35 (s, 54H), δ 3.36 (s, 6H), δ 5.94 (s, 2H).

<Example 2> Synthesis of (Et,Me-NHC)La[N(SiMe ₃ ) ₂ ] ₃ Synthesized according to Synthesis Example 1, wherein R ₁ and R ₂ are ethyl and methyl, respectively. , R ₃ and R ₄ are each hydrogen, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 3-2 below.

The synthesized compound is a colorless crystalline solid, the yield is 60.26%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ0.36 (s, 54H), δ1.10 (t, 3H), δ3.40 (s, 3H), δ3.86 (q, 2H), δ6 .00 (s, 1H), δ 6.10 (s, 1H).

<Example 3> Synthesis of (Et, Me-NHC)Y[N(SiMe ₃ ) ₂ ] ₃ Synthesized according to Synthesis Example 1, wherein R ₁ and R ₂ are ethyl and methyl, respectively. , R ₃ and R ₄ are each hydrogen, Ln is yttrium (Y), and the chemical formula of the synthesized compound is as shown in Chemical Formula 3-3 below.

The synthesized compound is a colorless crystalline solid, the yield is 57.5%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ0.39 (s, 54H), δ0.94 (t, 3H), δ3.52 (s, 3H), δ3.85 (q, 2H), δ5 .86 (s, 1H), δ 5.98 (s, 1H).

<Example 4> Synthesis of ( ⁱ Pr,Me-NHC)La[N(SiMe ₃ ) ₂ ] ₃ Synthesized according to Synthesis Example 1, wherein R ₁ and R ₂ are each iso-propyl, is methyl, R ₃ and R ₄ are each hydrogen, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 3-4 below.

The synthesized compound is a white crystalline solid, the yield is 52.44%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ0.35 (s, 54H), δ1.18 (d, 6H), δ3.41 (s, 3H), δ4.71 (m, 1H), δ6 .03 (s, 1H), δ 6.24 (s, 1H).

<Example 5> Synthesis of ( ⁱ Pr, Me, Me, Me-NHC) La[N(SiMe ₃ ) ₂ ] ₃ Synthesized according to Synthesis Example 1, wherein R ₁ and R ₂ are each iso-propyl, methyl, R ₃ and R ₄ are each methyl, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 3-5 below.

The synthesized compound is a brown crystalline solid, the yield is 77%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ0.30 (s, 54H), δ1.34 (d, 6H), δ1.37 (s, 3H), δ1.58 (s, 3H), δ3 .38 (s, 3H), δ 4.30 (s, 1H).

（前記化学式４－１において、^tＢｕは、ｔｅｒｔ－ブチルである） <Example 6> Synthesis of (Me, Me-NHC)La(O ^t Bu) ₃ Synthesized according to Synthesis Example 2, in the reaction chemical formula (2), R ₁ and R ₂ are each methyl, and R ₃ and R ₄ are each hydrogen, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 4-1 below.

(In the chemical formula 4-1, ^t Bu is tert-butyl)

The synthesized compound is an orange crystalline solid, the yield is 31.77%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ 1.41 (s, 27H), δ 3.37 (s, 6H), δ 6.22 (s, 2H).

（前記化学式４－２において、^tＢｕは、ｔｅｒｔ－ブチルである） <Example 7> Synthesis of (Et,Me-NHC)La(O ^t Bu) ₃ Synthesized according to Synthesis Example 2, wherein R ₁ and R ₂ are ethyl and methyl, respectively, R ₃ and R ₄ are each hydrogen, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 4-2 below.

(In the chemical formula 4-2, ^t Bu is tert-butyl)

The synthesized compound is an orange crystalline solid, the yield is 30.46%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ1.14 (t, 3H), δ1.45 (s, 27H), δ3.39 (s, 3H), δ3.81 (q, 2H), δ6 .26(s, 1H), .delta.6.33(s, 1H).

（前記化学式４－３において、^tＢｕは、ｔｅｒｔ－ブチルである） <Example 8> Synthesis of (Et,Me-NHC)Y(O ^t Bu) ₃ Synthesized according to Synthesis Example 2, wherein R ₁ and R ₂ are ethyl and methyl, respectively, R ₃ and R ₄ are each hydrogen, Ln is yttrium (Y), and the chemical formula of the synthesized compound is shown in Chemical Formula 4-3 below.

(In the chemical formula 4-3, ^t Bu is tert-butyl)

The synthesized compound is an orange crystalline solid, the yield is 95.7%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ1.18 (t, 3H), δ1.48 (s, 27H), δ3.64 (s, 3H), δ4.16 (q, 2H), δ6 .13(s, 1H), .delta.6.22(s, 1H).

（前記化学式４－４において、^tＢｕは、ｔｅｒｔ－ブチルである） <Example 9> Synthesis of ( ⁱ Pr, Me-NHC)La(O ^t Bu) ₃ Synthesized according to Synthesis Example 2, wherein R ₁ and R ₂ are iso-propyl and methyl , R ₃ and R ₄ are each hydrogen, Ln is lanthanum (La), and the chemical formula of the synthesized compound is as shown in Chemical Formula 4-4 below.

(In the chemical formula 4-4, ^t Bu is tert-butyl)

The synthesized compound is an orange crystalline solid, the yield is 89.35%, and the measured ¹ H-NMR peaks are as follows.

¹ H-NMR (400 MHz, C ₆ D ₆ ): δ1.25 (d, 6H), δ1.41 (s, 27H), δ3.44 (s, 3H), δ4.48 (m, 1H), δ6 .28 (s, 1H), δ 6.41 (s, 1H).

[Experimental Example 1] Differential Scanning Calorimetry (DSC)
A differential scanning calorimetry (DSC) analysis for measuring the thermal properties of Examples 1-1, 1-2 and 1-4 was performed, and the results are shown in FIG.

The equipment used is DSC 214 Polyma from NETZSH, weighing approximately 10 mg of each sample, placing it in a closed high pressure gold plated Al pan, and then measuring from 50°C to 350°C at a heating rate of 10°C. bottom.

As a result of measurement, the melting points of the compounds of Examples 1-1, 1-2 and 1-4 were 153° C., 138° C. and 119° C., respectively.

The decomposition temperatures of the compounds of Examples 1-1, 1-2 and 1-4 were 257°C, 254°C and 257°C, respectively.

It was confirmed that the compounds synthesized in Examples 1-1, 1-2 and 1-4 all had decomposition temperatures of 250° C. or higher and had excellent thermal stability.

[Experimental Example 2] Thermogravimetric analysis (TGA)
Thermogravimetric analysis (TGA) of the synthesized compounds was performed. The instrument used during the thermogravimetric analysis was a TGA/DSC 1 STAR System from Mettler Toledo, using an Alumina crucible with a capacity of 50 μL. The compound was heated to 400° C. at a rate of 10° C./min, and argon (Ar) gas was injected at a rate of 200 mL/min.

The results of thermogravimetric analysis of the compounds of Examples 1-1 to 1-5 are shown in FIG. 2, and the results of thermogravimetric analysis of the compounds of Examples 1-7 and 1-9 are shown in FIG. .

As a result of thermogravimetric analysis, the temperature [T _1/2 ] at which the weight is reduced by half was 243° C. for the compound of Example 1-1, 247° C. for the compound of Example 1-2, and 247° C. for the compound of Example 1-3. was measured at 324°C, the compound of Examples 1-4 at 278°C, the compound of Examples 1-5 at 266°C, the compound of Examples 1-7 at 233°C, and the compound of Examples 1-9 at 216°C. rice field.

The amount of residue at 400° C. was 19.47% for the compound of Example 1-1, 17.29% for the compound of Example 1-2, and 43.79% for the compound of Example 1-3. , the compound of Examples 1-4 is 25.17%, the compound of Examples 1-5 is 18.46%, the compound of Examples 1-7 is 11.65%, and the compound of Examples 1-9 is 12.5%. It was measured as 64%.

Therefore, the weight of the compound synthesized according to Reaction Formula 1 is reduced by half at approximately 240° C. or higher, and the weight of the compound synthesized by Reaction Formula 2 is reduced by half at approximately 210° C. or higher. T _1/2 of the synthesized compound was generally higher than T _1/2 of the compound synthesized according to Reaction Formula 2. In addition, it was confirmed that the compounds synthesized according to Chemical Reaction Formulas 1 and 2 have excellent thermal stability.

[Production Example 1]
A rare earth thin film was deposited on a substrate by alternately applying the novel rare earth precursor synthesized according to Examples 1-1 to 1-6 of the present invention and the reactant O ₃ . The substrate used in this experiment is a p-type Si wafer with a resistance of 0.02 Ω·m. Prior to deposition, the p-type Si wafer was cleaned by sonicating (Ultrasonic) in acetone-ethanol-deionized water (DI water) for 10 minutes each. The native oxide thin film formed on the Si wafer was removed after being immersed in a 10% HF (HF:H2O=1:9) solution for 10 seconds.

A substrate was prepared by maintaining a temperature of 150 to 450°C, and the solid novel rare earth precursor synthesized in Example 1 was vaporized in a bubbler maintained at a temperature of 90 to 150°C. rice field.

As a purge gas, argon (Ar) was supplied to purge the remaining precursor and reaction gas in the deposition chamber, and the flow rate of argon was 1000 sccm. Ozone (O ₃ ) with a concentration of 224 g/cm ³ was used as the reaction gas, and each reaction gas was injected by adjusting the on/off of the pneumatic valve to form a film at the process temperature.

The ALD cycle included a sequence of 10/15 sec precursor pulse followed by 10 sec argon purge followed by 2/5/8/10 sec reactant pulse followed by 10 sec argon purge. The pressure of the deposition chamber was adjusted to 1-1.5 torr, and the deposition temperature was adjusted to 150-450.degree.

It was confirmed that lanthanum oxide and yttrium oxide thin films were formed using the compounds of Examples 1-1 to 1-6 as precursors.

[Production Example 2]
A lanthanum oxide thin film was deposited on a substrate under the same conditions as in Preparation Example 1, except that the novel rare earth precursors synthesized according to Examples 1-7 to 1-9 of the present invention were used.

It was confirmed that lanthanum oxide and yttrium oxide thin films could be formed using the compounds of Examples 1-7 to 1-9 as precursors.

[Production Example 3]
Using the novel rare earth precursors synthesized according to Examples 1-1 to 1-9 of the present invention, thin films containing rare earth elements were produced by chemical vapor deposition. A starting precursor solution containing the precursors synthesized according to Examples 1-1 to 1-9 was prepared.

This precursor starting solution was delivered to a vaporizer maintained at a temperature of 90-150° C. at a flow rate of 0.1 cc/min. The thus vaporized precursor was delivered to the deposition chamber using 50-300 sccm of helium carrier gas. Hydrogen (H ₂ ) and oxygen (O ₂ ) were used as reaction gases and supplied to the deposition chamber at a flow rate of 0.5 L/min (0.5 pm) respectively. The pressure of the deposition chamber was adjusted to 1-15 torr, and the deposition temperature was adjusted to 150-450.degree. Under these conditions, the vapor deposition process was performed for about 15 minutes.

It was confirmed that lanthanum oxide and yttrium oxide thin films could be formed using the compounds of Examples 1-1 to 1-9 as precursors.

The rare earth-containing precursor and one or more reactive gases may be introduced into the reaction chamber simultaneously by chemical vapor deposition, atomic layer deposition, or other combination.

As one example, the rare earth-containing precursor may be introduced in a single pulse and the two additional metal sources may be introduced together in separate pulses. Alternatively, the reaction chamber may already contain the reactant species prior to introducing the rare earth-containing precursor.

The reactant gas may be passed through a plasma system located remotely from the reaction chamber and decomposed into radicals. Alternatively, the rare earth-containing precursor may be continuously introduced into the reaction chamber while other metal sources are pulsed.

For example, in atomic layer deposition type processes, a vaporous rare earth-containing precursor is introduced into a reaction chamber where, after contacting a suitable substrate, excess rare earth-containing precursor is removed by purging the reaction chamber. can be removed from

An oxygen source is introduced into the reaction chamber where it reacts with the absorbed rare earth precursor in a self-limiting manner. Excess oxygen sources can be removed from the reaction chamber by purging and/or degassing the reaction chamber. If the desired film is a rare earth oxide film, the above steps may be repeated until the desired film thickness is obtained.

Through the above thin film production, the newly synthesized rare earth precursors of Examples 1-1 to 1-9 not only complement the problems of existing rare earth precursor thin film deposition, but also CVD, It was confirmed that it has excellent volatility and thermal stability applicable to ALD, and also has excellent reactivity with reaction gases.

In addition, uniform thin film deposition is possible through the novel rare earth precursor, thereby ensuring excellent thin film physical properties, thickness and step coverage.

The scope of the present invention is indicated by the appended claims rather than the foregoing detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents are considered within the scope of the present invention. should be construed as being within the scope of

Claims (9)

A compound represented by Chemical Formula 1 below.

In the chemical formula 1,
M is Y (yttrium) or lanthanum (La) ;
R ₁ to R ₆ are each independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
R ₇ to R ₉ are —OR ₁₀ ;
R ₁₀ is hydrogen ; a linear or branched alkyl group having 1 to 6 carbon atoms. R ₁ to R ₆ are each independently hydrogen, methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group and tert-butyl group; is any one selected from the group consisting of
R ₁₀ is any selected from the group consisting of hydrogen, methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group and tert-butyl group; 2. The compound of claim 1 , which is one . of chemical formula 1

is any one selected from the group consisting of ligands represented by the following chemical formulas 1a to 1j.

The compound according to claim 1, wherein the compound is any one selected from the group consisting of compounds represented by the following chemical formulas 1-5 to 1-7.

In the chemical formulas 1-5 to 1-7,
M is Y (yttrium) or lanthanum (La) ;
^t Bu is tert-butyl. A vapor deposition precursor comprising a compound represented by Formula 2 below .

In the chemical formula 2,
M is Y (yttrium) or lanthanum (La),
R ₁ to R ₆ are each independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
R ₇ to R ₉ are —OR ₁₀ or —N(R ₁₁ ) ₂ ;
R ₁₀ is hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms;
the R ₁₁ is Si(R ₁₂ ) ₃ ;
Each R ₁₂ is independently hydrogen; a linear or branched alkyl group having 1 to 6 carbon atoms. A method of making a thin film, comprising introducing the vapor deposition precursor of claim 5 into a chamber. 7. The thin film manufacturing method of claim 6 , wherein the thin film manufacturing method includes atomic layer deposition (ALD) or chemical vapor deposition (CVD). 7. The method of claim 6 , further comprising injecting at least one of hydrogen ( _H2 ), an oxygen (O) atom-containing compound, and a nitrogen (N) atom-containing compound as a reaction gas. The reaction gases include oxygen ( _O2 ), ozone ( _O3 ), water ( _H2O ), hydrogen peroxide ( _{H2O2 )} , nitrogen ( _N2 ), ammonia ( _NH3 ) and hydrazine ( _N2). H ₄ ) is any one or more selected from among.

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