KR100804413B1 - Organometallic Precursor for Zirconium Oxide Thin Film Deposition and Its Manufacturing Method - Google Patents

Abstract

The present invention relates to a novel zirconium oxide precursor represented by the following formula (1) and a method for producing the same, the zirconium oxide precursor synthesized according to the present invention is thermally stable and volatility is improved to be used advantageously in the production of zirconium oxide thin film Can be.

[Formula 1]

[In Formula 1, A is NR ² R ³ or ER ⁴ ; E is oxygen (O) or sulfur (S); R ¹ is hydrogen, methyl or ethyl; R ² and R ³ are independently of each other a C1-C4 alkyl group or SiR ⁵ _{3 with} or without fluorine; R ⁴ is a C1-C6 alkyl group with or without fluorine or SiR ⁵ ₃ ; R ⁵ is an alkyl group of C 1 -C 4.]

Zirconium Oxide Precursor, Zirconium Oxide, Thin Film, MOCVD, ALD

Description

Organometallic precursor for zirconium oxide thin film deposition and its manufacturing method {A PRECURSOR FOR ZIRCONIUM DIOXIDE THIN FILM DEPOSITION AND PREPARATION METHOD THEREOF}

^1-1 H-NMR of CpZr (NEtMe) ₃ prepared in Example 1

2-a prepared in Example _{^{4 CpZr (O i Pr) 3}} 1 H-NMR of the

¹ H-NMR of the embodiment CpZr (mp) ₃ prepared in Example 5 - 3

Figure 4-a prepared in Example _{^{6 CpZr (S t Bu) 3}} 1 H-NMR of the

5-Thermogravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) of CpZr (NEtMe) ₃ prepared in Example 1

6-Thermogravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) of CpZr (O ⁱ Pr) ₃ prepared in Example 4

7-Thermogravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) of CpZr (mp) ₃ prepared in Example 5

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel precursor for depositing zirconium oxide thin films, and relates to a zirconium organometallic compound useful as a zirconium oxide precursor and a manufacturing method thereof.

The rapid development of informatization and communication in the modern society with the development of digital technology is constantly demanding the development of devices with the ability to process more information faster. Therefore, as not only the performance improvement of the system but also the high integration and ultra-high speed of the transistor, which are the core components of the device, are required, the size of the integrated circuit is continuously reduced to increase the switching speed and reduce the power loss. Accordingly, the transistor has been speeded up by reducing the channel distance and reducing the thickness of the gate oxide layer. However, conventionally used gate oxide film SiO ₂ has a problem that leakage current increases at 80 nm or less. Therefore, in order to overcome this limitation, application of high-k material having high dielectric constant and low dielectric loss is required. It becomes necessary. In particular, ZrO ₂ is of great interest because it has a large dielectric constant (~ 25), a large band gap (~ 5.8 eV), and is thermally stable upon contact with the Si interface. In the semiconductor device, a gate oxide film is manufactured through metal organic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD). Therefore, in order to deposit a desired oxide film using MOCVD or ALD process, the selection of a precursor suitable for the process is the most important problem. Considering mass production, especially in the production of uniform, dense and dense thin film coverings of the final oxide thin film, the precursor should have a sufficiently high vapor pressure below 100 ° C. and thermally sufficient during heating to vaporize. It should be stable. More preferably, the precursor should be a low viscosity liquid compound or a low melting point solid at room temperature in order to ensure stable vapor pressure and prevent the incorporation of particles into the vaporizer. In the case of MOCVD process, it should be rapidly decomposed without decomposing organic materials at substrate temperature of 250 ℃ ~ 500 ℃. In case of ALD process, ligand is completely and quickly decomposed and removed by ozone or water used as oxidant. Should be.

Previously known precursors for the production of zirconium oxide thin films can be classified into four types according to the type of ligand coordinated in the zirconium core metal.

The first is an inorganic salt precursor such as ZrCl ₄ , ZrI ₄ or Zr (NO ₃ ) ₄ . However, these inorganic salt precursors are not only low volatility but also high melting point solid precursors, which have a problem of incorporation of particles into the substrate during vaporization and serious contamination of impurities in forming high purity zirconium oxide thin films. (AC Jones, PR Chalker, J. Phys. D: Appl . Phys., 2003, 36, R80).

Second is zirconium alkoxide (Zr (OR) ₄ ). Zirconium alkoxide precursors have been reported to be the most applied researches for MOCVD and ALD precursors for zirconium thin film deposition because they have higher volatility and lower deposition temperature than inorganic salt precursors of zirconium. However, zirconium ions, the central metals, have a relatively large ion radius of 0.72 Å and tend to be dimers or polymers to satisfy 6-8 coordination (DC Bradley, RC Mehrotra and DP Gaur, Metal Alkoxides , Academic Press, New York, 1978, pp 10-12) Not only can it reduce volatility, but it also leads to problems in achieving a stable vapor pressure. Therefore, Zr (O ^t Bu) ₄ (BJ Gould, IM which induced steric hindrance by introducing a large alkyl group such as tert -butyl group in order to prevent vapor pressure drop due to dimer or polymer formation in storage or gas phase. Povey, ME Pemble and WR Flavell, J. Mater. Chem . , 1994, 4 , 1815) have been used in recent years to improve the vapor pressure characteristics by making precursors into monomers by introducing double-digit donor ligands. Has been reported. In the latter case, a typical example a (O ^t Bu) Zr introducing 1-methoxy-2-methyl- 2-propoanolate (mmp) ligand ₂ (mmp) ₂ and _{Zr (mmp) 4 (PA Williams} , JL Roberts, AC Jones, PR Chalker, NL Tobin, JF Bickley, HO Davies, LM Smith and TJ Leedham, Chem . Vap . Deposition , 2002, 8 , 163) has been reported to produce zirconia thin films at 350 to 600 ° C using conventional MOCVD or LI-MOCVD, but the carbon residue in the final thin film is rather high. In addition, [Zr (O ⁱ Pr) ₃ (dmap)] ₂ and [Zr (O ⁱ Pr) ₃ (bis-) having introduced 2-dimethylaminoethanol (dmae) and 1-dimethylamino-2-propanol (dmap) as ligands. dmap)] ₂ (KA Fleeting, P. O'Brien, AC Jones, DJ Otway, AJP White and DJ Williams, J. Chem. Soc ., Dalton Trans ., 1999, 2853), Zr (O ^t Bu) ₂ (dmae) ₂ ] ₂ (R. Matero, M. Ritala, M. Leskala, AC Jones, PA Williams, JF Bickley, A. Steiner, TJ Leedham and HO Davies, J. Non-Cryst. Solids, 2002, 303, 24) have been reported, all of which are known to cause disproportionation during heating for vaporization, resulting in unstable vapor pressure (AC Jones, TJ Leedham, PJ Wright, MJ Crosbie, DJ Williams, PA Lane and P. O '). Brien, Mater. Res. Soc. Symp . Proc ., 1998, 495 , 11).

Third, a zirconium precursor containing β-diketonate can be mentioned. These compounds sufficiently satisfy the coordination around zirconium to form stable compounds, but require high temperatures to obtain sufficient vapor pressure for thin film deposition (RC Smith, T. Ma, N. Hoilien, LY Tsung, MJ Bevan, L. Colombo, J. Roberts, SA Campbell and W. Gladfelter, Adv . Mater. Opt. Electron ., 2000, 10 , 105), due to the high decomposition temperature, carbon contamination in the final film presents a serious problem. In addition, in the case of Zr (tfac) ₄ (M. Balog, M. Schreiber, J. Cryst. Growth, 1972, 17, 298), in which fluorine is contained in the β-diketonate ligand, the vapor pressure is improved, but It is difficult to apply it as a precursor for zirconia thin film deposition because it decomposes the silicon substrate.

Fourth, zirconium compounds in which amido ligands are coordinated have recently been reported to be the most applied precursors for MOCVD and ALD processes. In particular, all zirconium amido compounds represented by Zr (NMeEt) ₄ or Zr (NEt ₂ ) ₄ exist in low viscosity liquid state at room temperature, have high vapor pressure, and easy removal of amido ligands by ozone and water vapor. It is most widely used as a precursor of zirconia thin film manufacturing using the process (DM Hausmann, E. Kim, J. Becker, and LG Gordon, Chem . Mater ., 2002, 14 , 4350). However, it has recently been reported that zirconium amido compounds are very reactive and thus do not easily be stored for long periods of time. In particular, zirconium amido compounds have a low thermal stability (below 250 ° C.) to decompose during vaporization and thus greatly affect the quality of the thin film.

In order to solve the problems of the existing zirconium precursors, the present inventors have developed a novel zirconium precursor having high thermal stability, high volatility, and stable vapor pressure.

An object of the present invention is to provide a zirconium oxide precursor having high thermal stability and excellent volatility for depositing a high quality zirconium oxide film by applying an organometallic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) process.

The present invention provides a novel zirconium oxide precursor represented by the following formula (1) to achieve the above object:

[Formula 1]

[In Formula 1, A is NR ² R ³ or ER ⁴ ; E is oxygen (O) or sulfur (S); R ¹ is hydrogen, methyl or ethyl; R ² and R ³ are independently of each other a C1-C4 alkyl group or SiR ⁵ _{3 with} or without fluorine; R ⁴ is a C1-C6 alkyl group with or without fluorine or SiR ⁵ ₃ ; R ⁵ is an alkyl group of C 1 -C 4.]

More preferably, in Chemical Formula 1, A is NR ² R ³ , R ¹ is hydrogen or methyl, R ² and R ³ are independently of each other a zirconium oxide precursor and A is ER ⁴ ; A zirconium oxide precursor is illustrated wherein E is O or S, R ¹ is hydrogen or methyl and R ⁴ is isopropyl, t-butyl or 3-methyl-3-pentyl.

The zirconium oxide precursor of Formula 1 includes the compounds of Formulas 1-1 and 1-2:

[Formula 1-1]

[Formula 1-2]

[Wherein, R ¹ , R ² , R ³ , R ⁴ and E are the same as defined in the formula (1).]

The zirconium oxide precursors defined by Chemical Formula 1 may be easily prepared from the following Schemes 1 to 4, and the synthesis of the zirconium oxide precursors according to the following Schemes 1 to 4 may include a nonpolar solvent such as benzene, hexane, pentane, and toluene. It is prepared using a polar solvent such as diethyl ether or tetrahydrofuran as a solvent.

The zirconium oxide precursor [R ¹ CpZr (A) ₃ ] of the formula 1 according to the present invention may be prepared by using the compound [R ¹ CpZr (X) ₃ ] represented by the following formula 2 as a starting material It may be prepared by reacting with compound MA of Formula 3:

Scheme 1

R ¹ CpZr (X) ₃ (2) + 3 MA (3) → R ¹ CpZr (A) ₃ (1) + 3 MX

[Wherein A and R ¹ are the same as defined in Formula 1, X represents a chlorine atom, bromine atom or iodine atom, and M represents lithium, sodium or potassium.]

As shown in Scheme 1, 1 equivalent of Compound 2 and 3 equivalent of Compound 3 are dissolved in a nonpolar solvent such as benzene, hexane, pentane, toluene or a polar solvent such as diethyl ether or tetrahydrofuran, After stirring for 12 hours to induce a substitution reaction, and filtered under reduced pressure, the solvent was removed under reduced pressure from the resulting filtrate to obtain a zirconium oxide precursor compound of formula (1).

The zirconium oxide precursor [R ¹ CpZr (A) ₃ ] according to the present invention is represented by the following Scheme 2, using the compound [R ¹ CpZr (X) ₃ ] represented by the following Formula 2 as a starting material. It may also be prepared by reacting with compound HA of Formula 4:

Scheme 2

R ¹ CpZr (X) ₃ (2) + 3 HA (4) + 3 NR ¹¹ ₃ → R ¹ CpZr (A) ₃ (1) + 3 NR ¹¹ ₃ HCl

[Wherein A and R ¹ are the same as defined in Formula 1, X represents a chlorine atom, bromine atom or iodine atom, and R ¹¹ represents methyl or ethyl.]

As shown in Scheme 2, 1 equivalent of the compound of Formula 2 and 3 + x equivalent of the compound of Formula 4 (0 <x <2) are converted to a nonpolar solvent such as benzene, hexane, pentane, toluene, or diethyl ether or tetrahydrofuran. After dissolving in a polar solvent such as 3 + x equivalent tertiary amine (NR ¹¹ ₃ , R ¹¹ = CH ₃ or CH ₂ CH ₃ ), and then stirred at room temperature for about 12 hours to induce a substitution reaction, a white solid Precipitated, and the filtrate obtained by filtration under reduced pressure to remove the white solid, the solvent was removed under reduced pressure to obtain a zirconium oxide precursor compound of formula (1).

In addition, the zirconium oxide precursor [R ¹ CpZr (A) ₃ ] according to the present invention is a starting material of the compound [Zr (NR ² R ³ ) ₄ ] represented by the following Formula 5, as shown in Scheme 3 below. It may be prepared by reacting with a compound of Formula 6 R ¹ C ₅ H ₅

Scheme 3

Zr (NR ² R ³ ) ₄ (5) + R ¹ C ₅ H ₅ (6) → R ¹ CpZr (NR ² R ³ ) ₃ (1) + HNR ² R ³

[Wherein, R ¹ , R ² and R ³ are the same as defined in the formula (1).]

As shown in Scheme 3, 1 equivalent of Compound 5 is dissolved in a non-polar solvent such as benzene, hexane, pentane, toluene, or a polar solvent such as diethyl ether or tetrahydrofuran, and then Compound 1 + x equivalent of Formula 6 ( After adding 0 <x <1), the reaction was induced at room temperature for about 12 hours to induce a substitution reaction, and after completion of the reaction, the solvent was removed under reduced pressure to obtain a zirconium oxide precursor compound of Chemical Formula 1.

In addition, the zirconium oxide precursor [R ¹ CpZr (A) ₃ ] of the formula 1 according to the present invention is a compound represented by the following formula 1-1 [R ¹ CpZr (NR ² R ³ ) ₃ ] May be prepared by reacting with compound HER ⁴ of formula 7:

Scheme 4

R ¹ CpZr (NR ² R ³ ) ₃ (1-1) + HER ⁴ (7) → R ¹ CpZr (ER ⁴ ) ₃ (1-2) + HNR ² R ³

[Wherein, R ¹ , R ² , R ³ , R ⁴ and E are the same as defined in the formula (1).]

As shown in Scheme 4, 1 equivalent of Compound 1-1 is dissolved in a non-polar solvent such as benzene, hexane, pentane, toluene, or a polar solvent such as diethyl ether or tetrahydrofuran, and then Compound 1 + x After adding the equivalent (0 <x <1) and stirring at room temperature for about 12 hours to induce a substitution reaction, and after completion of the reaction to remove the solvent under reduced pressure to obtain a zirconium oxide precursor compound of formula 1-2.

The novel zirconium oxide precursor according to the present invention is a precursor for producing various oxide thin films including zirconium oxide including zirconia thin film, and is particularly widely used in semiconductor manufacturing processes, such as organometallic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD). ) Can be preferably applied to the process.

 The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

All experiments were performed in an inert argon or nitrogen atmosphere using a glove box or Schlenk line. The structure of each reaction product obtained in Examples 1 to 3 was analyzed using ¹ H nuclear magnetic resonance ( ¹ H NMR) and carbon atom nuclear magnetic resonance ( ¹³ C NMR).

zirconium Precursor  Produce

Example 1 Synthesis of Cyclopentadienyl zirconium (IV) tri (ethylmethylamide) [CpZr (NEtMe) ₃ ]

Into a flame-dried 125 mL Schlenk flask containing 100 mL of hexane, 32.36 g (100 mmol, 1.00 equiv) of tetrakis (ethylmethylamino) zirconium (IV) were dissolved, followed by stirring 66.10 g of cyclopentadiene with stirring. mmol, 1.00 equiv) was slowly added while maintaining the temperature at −20 ° C., and the reaction temperature was slowly raised to room temperature. After the reaction mixture was stirred for 2 hours at room temperature, the reaction was terminated. After completion of the reaction, the solvent was removed under reduced pressure to give a yellow liquid. Distillation under reduced pressure (boiling point: 81 ° C. at 0.1 mm Hg) to increase the purity of the resulting liquid yielded 23.2 g (yield 70%) of the title compound as a yellow liquid.

¹ H NMR (C ₆ D ₆ ): δ 6.07 (s, 5H, -C ₅ H ₅ ), 3.22, 3.19 (q, 6H, -N (C H ₂ CH ₃ ) (CH ₃ )), 2.87 (s , 9H, -N (CH ₂ CH ₃ ) (C H ₃ )), 1.03 (t, 9H, -N (CH ₂ C H ₃ ) (CH ₃ ))

¹³ C NMR (C ₆ D ₆ ): δ 110.74 ( -C ₅ H ₅ ), 51.90 (-N ( C H ₂ CH ₃ ) (CH ₃ )), 40.71 (-N (CH ₂ CH ₃ ) ( C H ₃ )), 15.99 (-N (CH ₂ C H ₃ ) (CH ₃ ))

Example 2 Synthesis of Cyclopentadienyl zirconium (IV) tri (ethylmethylamide) [CpZr (NEtMe) ₃ ]

In a flame-dried 1000 mL Schlenk flask, 26.27 g (100 mmol, 1.00 equiv) of cyclopentadienylzirconium (IV) trichloride is suspended in 200 mL of hexane. While stirring this mixed solution, 20 g (307.46 mmol) of lithium ethylmethylamide (LiNEtMe), which is a suspension, was slowly added to 300 mL of hexane while maintaining the temperature at -20 ° C, and the reaction temperature was slowly raised to room temperature. After the reaction mixture was stirred at room temperature for 24 hours, the reaction was terminated. After completion of the reaction, precipitated lithium chloride (LiCl) was separated by filtration under reduced pressure to obtain a yellow filtrate. The filtrate was again depressurized to completely remove the solvent and distilled under reduced pressure (boiling point: 81 ° C. at 0.1 mmHg) to increase the purity of the resulting liquid to give 28.76 g (yield 87%) of the title compound as a yellow liquid.

¹ H NMR (C ₆ D ₆ ): δ 6.07 (s, 5H, -C ₅ H ₅ ), 3.22, 3.19 (q, 6H, -N (C H ₂ CH ₃ ) (CH ₃ )), 2.87 (s , 9H, -N (CH ₂ CH ₃ ) (C H ₃ )), 1.03 (t, 9H, -N (CH ₂ C H ₃ ) (CH ₃ ))

¹³ C NMR (C ₆ D ₆ ): δ 110.74 ( -C ₅ H ₅ ), 51.90 (-N ( C H ₂ CH ₃ ) (CH ₃ )), 40.71 (-N (CH ₂ CH ₃ ) ( C H ₃ )), 15.99 (-N (CH ₂ C H ₃ ) (CH ₃ ))

Example 3 Synthesis of Cyclopentadienyl zirconium (IV) tri (ethylmethylamide) [CpZr (NEtMe) ₃ ]

In a flame-dried 1000 mL Schlenk flask, 26.27 g (100 mmol, 1.00 equiv) of cyclopentadienylzirconium (IV) trichloride was suspended in 500 mL of diethyl ether. While stirring the mixed solution, 18 g (304.52 mmol) of ethylmethylamine (HNEtMe) and 31 g (306.35 mmol) of triethylamine (NEt ₃ ) were slowly added while maintaining the temperature at −20 ° C., and the reaction temperature was slowly raised to room temperature. . After the reaction mixture was stirred at room temperature for 24 hours, the reaction was terminated. After completion of the reaction, triethylammonium chloride (Et ₃ N.HCl) precipitated was separated by filtration under reduced pressure to obtain a yellow filtrate. The filtrate was depressurized again to completely remove the solvent and distilled under reduced pressure (boiling point: 81 ° C. at 0.1 mmHg) to increase the purity of the resulting liquid to give 18.4 g (yield 56%) of the title compound as a yellow liquid.

¹ H NMR (C ₆ D ₆ ): δ 6.07 (s, 5H, -C ₅ H ₅ ), 3.22, 3.19 (q, 6H, -N (C H ₂ CH ₃ ) (CH ₃ )), 2.87 (s , 9H, -N (CH ₂ CH ₃ ) (C H ₃ )), 1.03 (t, 9H, -N (CH ₂ C H ₃ ) (CH ₃ ))

¹³ C NMR (C ₆ D ₆ ): δ 110.74 ( -C ₅ H ₅ ), 51.90 (-N ( C H ₂ CH ₃ ) (CH ₃ )), 40.71 (-N (CH ₂ CH ₃ ) ( C H ₃ )), 15.99 (-N (CH ₂ C H ₃ ) (CH ₃ ))

Example 4 Synthesis of Cyclopentadienyl zirconium (IV) tri (isopropoxide) [CpZr (O ⁱ Pr) ₃ ]

33.06 g (100 mmol, 1.00 equiv) of cyclopentadienyl zirconium (IV) triethylmethylamide (CpZr (NEtMe) ₃ ) was added to a flame-dried 125 mL Schlenk flask containing 100 mL of hexane, and then stirred. 18.03 g (300 mmol, 3.00 equiv) of isopropanol was slowly added thereto while maintaining the temperature at -40 ° C, and the reaction temperature was slowly raised to room temperature. The mixed reaction solution was stirred for 2 hours at room temperature and terminated. After completion of the reaction, the solvent was removed under reduced pressure to give a yellow viscous liquid. Distillation under reduced pressure (boiling point: 74 ° C. at 1.0 mmHg) in order to increase the purity of the resulting liquid yielded 20.01 g (yield 60%) of the title compound as a yellow liquid.

¹ H NMR (C ₆ D ₆ ): δ 6.26 (s, 5H, -C ₅ H ₅ ), 4.19 (hept, 3H, -OC H (CH ₃ ) ₂ ), 1.13, 1.11 (d, 18H, -OCH (C H ₃ ) ₂ )

¹³ C NMR (C ₆ D ₆ ): δ 111.57 ( -C ₅ H ₅ ), 72.54 (-O C H (CH ₃ ) ₂ ), 27.41 (18H, -OCH ( C H ₃ ) ₂ )

Example 5 Synthesis of Cyclopentadienyl zirconium (IV) tri (3-methyl-3-pentoxide) [CpZr (mp) ₃ ]

33.06 g (100 mmol, 1.00 equiv) of pentadienyl zirconium (IV) triethylmethylamide (CpZr (NEtMe) ₃ ) was added to a flame-dried 125 mL Schlenk flask containing 100 mL of hexane, and then stirred. 30.66 g (300 mmol, 3.00 equiv) of 3-methyl-3-pentanol was slowly added while maintaining the temperature at -40 ° C, and the reaction temperature was slowly raised to room temperature. The mixed reaction solution was stirred for 2 hours at room temperature and terminated. After completion of the reaction, the solvent was removed under reduced pressure to give a yellow viscous liquid. Distillation under reduced pressure (boiling point: 130 ° C. @ 0.4 mmHg) to increase the purity of the resulting liquid yielded 24.84 g (yield 54%) of the title compound as a yellow liquid.

¹ H NMR (C ₆ D ₆ ): δ 6.34 (s, 5H, -C ₅ H ₅ ), 1.44, 1.41 (q, 12H, -OC ((CH ₃ ) (C H ₂ CH ₃ ) ₂ ) ,, 1.12 (s, 9H, -OC ((C H ₃ ) (CH ₂ CH ₃ ) ₂ )), 1.12 (t, 18H, -OC ((CH ₃ ) (CH ₂ C H ₃ ) ₂ ))

¹³ C NMR (C ₆ D ₆ ): δ 111.24 ( -C ₅ H ₅ ), 78.8 (-O C ((CH ₃ ) (CH ₂ CH ₃ ) ₂ )), 34.7 (-OC ((CH ₃ ) ( C H ₂ CH ₃ ) ₂ )), 26.3 (-OC (( C H ₃ ) (CH ₂ CH ₃ ) ₂ )), 7.6 (-OC ((CH ₃ ) (CH ₂ C H ₃ ) ₂ ))

Example 6 Synthesis of Cyclopentadienyl zirconium (IV) tri (t-butylthioleate) [CpZr (S ^t Bu) ₃ ]

33.06 g (100 mmol, 1.00 equiv) of pentadienyl zirconium (IV) triethylmethylamide (CpZr (NEtMe) ₃ ) was added to a flame-dried 125 mL Schlenk flask containing 100 mL of hexane, and then stirred. While 27.06 g (300 mmol, 3.00 eq) of 2-methyl-2-propanethiol was slowly added while maintaining the temperature of -40 ° C, the reaction temperature was slowly raised to room temperature. The mixed reaction solution was stirred for 2 hours at room temperature and terminated. After completion of the reaction, the solvent was removed under reduced pressure to give a yellow viscous liquid. To increase the purity of the resulting liquid, distillation under reduced pressure (boiling point: 42°C@5.8 mmHg) gave 16.95 g (yield 40%) of the title compound as a yellow liquid.

¹ H NMR (C ₆ D ₆ ): δ 6.29 (s, 5H, -C ₅ H ₅ ), 1.58 (s, 9H, -SC (C H ₃ ) ₃ )

¹³ C NMR (C ₆ D ₆ ): δ 113.34 ( -C ₅ H ₅ ), 52.19 (-S C (CH ₃ ) ₃ ), 37.02 (-SC ( C H ₃ ) ₃ )

Analysis of Zirconium Precursors

For the structural analysis of the respective zirconium oxide precursors prepared in Examples 1 to 6, each compound was dissolved in C ₆ D ₆ , and the results of ¹ H-NMR analysis are shown in FIGS. 1 to 4. Meanwhile, in order to measure thermal stability, volatility, and decomposition temperature of the zirconium oxide precursors synthesized in Examples 1 to 5, respectively, thermogravimetric analysis / differential thermal analysis, TGA / DTA) method was used. The TGA / DTA method injected argon (Ar) gas at a rate of 45 L / min while warming the product to 500 ° C at a rate of 10 ° C / min. TGA / DTA graphs of the respective zirconium complexes synthesized in Examples 1, 4 and 5 are shown in FIGS. 5 to 7, respectively.

The zirconium precursor compounds newly synthesized in the present invention from the DTA graphs of FIGS. 5 to 7 all had pyrolysis temperatures of 260 ° C. or higher, which is higher than that of the conventionally known tetrakisethylmethylaminozirconium (Zr (NEtMe) ₄ ) compound. As indicating the temperature, the zirconium oxide precursor synthesized according to the present invention was found to be a precursor having improved thermal stability.

As described above, the novel zirconium oxide precursor compounds, which are precursors for the zirconium oxides of the present invention, are less sensitive to moisture and advantageous in storage, in particular metal organic chemical vapor deposition (MOCVD) or atomic layers, which require good quality of oxide films. As a zirconium precursor used in the deposition method (ALD) is inferior, it can be usefully used as a precursor for producing an oxide thin film containing zirconium oxide.

Claims (7)

Method of preparing a zirconium thin film by depositing a zirconium oxide precursor represented by the formula (1). [Formula 1]

[In Formula 1, A is NR ² R ³ or ER ⁴ ; E is oxygen (O) or sulfur (S); R ¹ is hydrogen, methyl or ethyl; R ² and R ³ are independently of each other a C1-C4 alkyl group or SiR ⁵ _{3 with} or without fluorine; R ⁴ is a C1-C6 alkyl group with or without fluorine or SiR ⁵ ₃ ; R ⁵ is an alkyl group of C 1 -C 4.] The method of claim 1, A is NR ² R ³ , R ¹ is hydrogen or methyl, and R ² and R ³ are independently of each other methyl or ethyl by depositing a zirconium oxide precursor to prepare a zirconium thin film. The method of claim 1, By depositing a zirconium oxide precursor, wherein A is ER ⁴ , E is O or S, R ¹ is hydrogen or methyl, and R ⁴ is isopropyl, t-butyl or 3-methyl-3-pentyl Method of manufacturing zirconium thin film. A method for producing a zirconium oxide precursor of formula (1) comprising reacting a zirconium compound represented by Formula 2 with an alkali metal salt of an amide represented by Formula 3, an alkali metal salt of an alkoxide, or an alkali metal salt of thiolate. [Formula 1]

 [Formula 2]

[Formula 3] MA [Wherein A and R ¹ are the same as defined in Formula 1 of claim 1, X represents a chlorine atom, bromine atom or iodine atom, and M represents lithium, sodium or potassium.] A method for producing a zirconium oxide precursor of formula (1) comprising reacting a zirconium compound represented by Formula 2 with a compound represented by Formula 4. [Formula 1]

 [Formula 2]

[Formula 4] HA [Wherein A and R ¹ are the same as defined in Formula 1 of claim 1, and X represents a chlorine atom, bromine atom or iodine atom.] delete The method according to any one of claims 4 to 5, A method for preparing a zirconium oxide precursor of formula (I) further comprising the step of reacting with a compound of formula (7). [Formula 1]

[Formula 7] HER ⁴ [Wherein E and R ⁴ are the same as defined in the formula (1) of claim 1]

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