KR100961562B1 - Novel siliconiv complexes and preparation method thereof - Google Patents

Abstract

The present invention relates to a novel silicone (IV) complex and a method for preparing the same, specifically a silicone complex represented by the following formula (1), wherein the complex in which the dialkylamino group is coordinated in silicon is thermally stable, stable in air, and volatile. New silicon useful as a precursor for chemical vapor deposition of silicon or silicon oxide thin films that can be advantageously used to produce high quality silicon or silicon oxide thin films due to high and no chemical contamination of carbon or halogen when forming thin films by chemical vapor deposition (CVD) (IV) complexes and methods for their preparation.

[Formula 1]

SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m

Wherein R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently C ₁ -C ₇ linear or branched alkyl, m, n is an integer ranging from 1 to 3.

Silicon, complex, silicon oxide, thin film, chemical vapor deposition

Description

New silicone complex and preparation method thereof {NOVEL SILICON (IV) COMPLEXES AND PREPARATION METHOD THEREOF}

The present invention relates to a novel silicon complex, to a compound useful as a precursor for chemical vapor deposition of a silicon or silicon oxide thin film and a method for producing the same.

Silicon oxide has been widely used as an insulator because of its stable, high quality silicon-silicon oxide interface and excellent electrical insulation properties. Recently, polycrystalline silicon thin films are used for thin film transistors (TFT), solar cells, and the like.

Metal Organic Chemical Vapor Deposition (MOCVD) process, which is used to manufacture various oxide thin films in the thin film manufacturing technology, is relatively simple in equipment, uniform in layer covering, easy to control ingredients, and difficult to convert to mass production. There is no advantage. In order to manufacture a thin film using such a MOCVD process, it is essential to develop a precursor material and to understand its characteristics. The precursors for MOCVD must have a sufficiently high vapor pressure below 200 ° C, be thermally stable enough for heating to vaporize, and decompose rapidly at the substrate temperature of 350 to 500 ° C without decomposition of organic materials, etc. Should be stable enough to air and moisture while. In addition, it should be non-toxic or less toxic to the precursor itself or to the decomposition products, the synthesis method should be simple and the raw material cost should be low.

There are four major precursors that have been used to make silicon compounds into thin films: silanes, silane chlorides, alkoxide compounds and β -diketonates.

Silane is a gas at room temperature, stable to high pressures and impacts, but burns or explodes when mixed with oxygen. It should also be handled with care as it reacts with moisture to form powders or particles. Silane tetrachloride (SiCl ₄ ) is a precursor of atomic layer deposition (ALD) with H ₂ O. A silicon oxide thin film is produced at a reactant pressure of 1-10 Torr and a temperature of 600-800 ㅀ K. (See JW Klaus, AW Ott, JM Johnson, and SM George, Appl. Phys. Lett. 1997 , 70 , 1092), and reacts sensitively to moisture as well as silanes to produce thin films. The surface may be contaminated with chlorides during the process. Dichlorosilanes (SiH ₂ Cl ₂ ) are also used to prepare silicon oxide thin films at 300 ° C. using atomic layer deposition with O ₂ or O ₃ ( Japanese Journal of Applied Physics, Part 2: Letters & Express Letters 2004 , 43 (3A) , L328-L33).

Among the alkoxide precursors, tetraethylorthosilicate (TEOS), which is most commonly used as a precursor of silicon oxide thin films, is liquid at room temperature and is easy to handle, but it reacts slowly with hydrolysis to SiO ₂ and ethanol. This precursor forms a thin film at a high temperature of about 400-900 ° C by LPCVD (Low-Pressure Chemical Vapor Deposition) or APCVD (Atmospheric Pressure Chemical Vapor Deposition) (J. Crowell et al . , J. Vac. Sci). A 1990 , 8 , 1864; L. Tedder et al. , J. Appl. Phys. 1991 , 69 , 7037; M. Islam Raja et al., J. Vac. Sci. Technol. B 1993 , 11 , 720 And D. Williams et al . , J. Electrochem. Soc. 1988 , 134 , 657).

In addition, compounds containing β -diketonate include SiClMe (acac) ₂ , SiClPh (acac) ₂ , SiMe ₂ (acac) ₂ (acac = acetylacetonate), which are very unstable and have low yields. There is this. Si (OAc) ₂ (acac) ₂ and SiX ₂ (thd) ₂ (X = Me, O ^t Bu, O ^t Am, thd = 2,2,6,6-tetramethyl-3,5-heptanedion) Although more stable, compounds containing β -diketonate have the disadvantage of high deposition temperature during the MOCVD process due to high thermal stability (C. Xu, et al . , Inorg . Chem . 2004 , 43 , 1568); [ R. West, J. Am . Chem . Soc . 1958 , 80 , 3246; RM Pike et al . , J. Am . Chem . Soc . 1966 , 88 , 2972; DW Thompson, Inorg. Chem. 1969 , 8 , 2015] and KM Taba et al. , J. Organomet. Chem. 1985 , 280 , 27).

The present inventors have introduced a novel ligand that can solve the problems of the compounds to develop a novel precursor for depositing silicon or silicon oxide thin films with improved thermal stability and volatility.

It is an object of the present invention to provide a thermally stable and increased volatility silicon compound precursor that is capable of forming high quality silicon or silicon oxide thin films.

In order to achieve the above object, the present invention provides a novel silicone compound precursor, wherein a dialkylamino group is coordinated to silicone, represented by the following formula (1).

[Formula 1]

SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m

Wherein R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently C ₁ -C ₇ linear or branched alkyl, m, n is an integer ranging from 1 to 3.

In addition, the present invention provides a method for producing a silicon complex compound of formula (1) characterized in that the reaction of the silicon compound of formula (2) and the alkali metal salt of formula (3).

[Formula 1]

SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m

[Formula 2]

SiR ¹ _m Cl _{4 -m}

(3)

MOCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵

In Formula 1, Formula 2 and Formula 3, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently C ₁ -C ₇ Linear or branched alkyl, m, n is an integer ranging from 1 to 3, and M is hydrogen or an alkali metal.

The present invention also provides a method for growing a silicon thin film or a silicon oxide thin film using the above-described silicon complex compound as a precursor.

The present invention also provides a method for growing a silicon thin film or a silicon oxide thin film, characterized in that the method for growing the thin film by metal organic chemical vapor deposition (MOCVD).

The present invention also provides a silicon thin film or silicon oxide thin film grown by the above method.

Hereinafter, the present invention will be described in more detail.

The present invention provides a novel silicone compound precursor, wherein a dialkylamino group is coordinated to silicon, represented by the following formula (1).

[Formula 1]

SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m

Wherein R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently C ₁ -C ₇ linear or branched alkyl, m, n is an integer ranging from 1 to 3.

In Chemical Formula 1, R ¹ , R ² , R ³ , R ^4, and R ⁵ are each independently an alkyl group selected from the group consisting of CH ₃ , C ₂ H _5, and CH (CH ₃ ) ₂ .

Specific examples of the silicone complex include tri (methyl)-(1-dimethylamino-2-methyl-2-propoxy) silicon (IV), di (methyl) -bis (1-dimethylamino-2-methyl-2-prop Foxy) silicone (IV) or (methyl) -tri (1-dimethylamino-2-methyl-2-propoxy) silicone (IV), etc. are mentioned.

The complex compound represented by Chemical Formula 1 according to the present invention may be prepared by a substitution reaction in a polar organic solvent with an alkali metal salt of a silicone compound represented by Chemical Formula 2 and an alcohol of Chemical Formula 3 as a starting material.

[Formula 2]

SiR ¹ _m Cl _{4 -m}

(3)

MOCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵

Wherein R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently C ₁ -C ₇ linear or branched alkyl as described above, m, n is an integer ranging from 1 to 3, M Is hydrogen or an alkali metal such as Li, Na and K.

The process of reacting the silicon starting material represented by Formula 2 with an alkali metal salt of an alcohol represented by Formula 3 to prepare a silicone complex of Formula 1 of the present invention may be represented by the following Scheme 1:

Scheme 1

SiR ¹ _m Cl _{4 -m} + (4-m) MOCR ² R ³ CH ₂ NR ⁴ R ⁵ → SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m + (4-m ) MCl

Wherein R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently C ₁ -C ₇ linear or branched alkyl, m, n is an integer ranging from 1 to 3, and M is hydrogen or Li Alkali metals such as, Na and K.

According to the reaction, for example, one equivalent of the compound of formula (2) and the compound (4-m) equivalent of formula (3) are dissolved in a polar solvent such as tetrahydrofuran, followed by a substitution reaction at room temperature for about 12 hours, and then filtered under reduced pressure. Then, the solvent is removed under reduced pressure from the resulting filtrate to obtain the compound of Formula 1.

In the above reaction, the compound of formula 2 containing halogen ions is reacted with MOCR ¹ R ² (CH ₂ ) _n NR ³ ₂ (compound of formula 3), which is an alkali metal salt, to (4-m) equivalents. MCl is produced.

The novel precursor for silicon or silicon oxide thin film according to the present invention represented by the formula (1) is a stable complex compound (chelate), an organic solvent having a non-polar alkyl group bonded to the α-carbon position with respect to the oxygen of the alkoxide to be bonded to the metal It can be present as a monomer because it has a high affinity for and a steric hindrance to prevent intermolecular interactions with oxygen and nitrogen of neighboring ligands. Due to these structural properties, the silicone complex compound of Formula 1 is a stable liquid at room temperature, has high solubility in organic solvents such as pentane, hexane, diethyl ether, tetrahydrofuran, toluene, etc. It does not include, and is stable at room temperature and stable in air, and advantageous in storage, and these can be used to obtain a higher quality silicon or silicon oxide thin film.

The novel silicon complexes of the present invention can be suitably applied to metal organic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) processes, particularly as a method of growing thin films widely used in semiconductor manufacturing processes. In particular, a method of growing the thin film is more preferably characterized by metal organic chemical vapor deposition (MOCVD).

As described above, the silicon complex compound of the present invention is a complex compound containing no halogen component and coordinated with a dialkylamino group in silicon, which is stable to moisture and advantageous in storage, and particularly, a metal organic chemical vapor deposition method (MOCVD) which requires excellent quality of oxide film. ) Or as a precursor of silicon used in atomic layer deposition (ALD), and thus can be usefully used as a precursor for producing an oxide thin film containing silicon.

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. Example 1 The structure of each reaction product obtained in to 3 hydrogen nuclei magnetic resonance ⁽¹ H nuclear magnetic resonance, NMR), carbon nuclear magnetic resonance ⁽¹³ C NMR), Fourier transform infrared spectroscopy (FTIR) analysis, elemental analysis and (elemental analysis, EA), thermogravimetric analysis / differential thermal analysis (TGA / DTA).

Preparation of Silicone Complexes

Example  One

Synthesis of tri (methyl)-(1-dimethylamino-2-methyl-2-propoxy) silicon (IV) [Si (CH ₃ ) ₃ (dmamp)]

To a 250 mL Schlenk flask containing tetrahydrofuran (150 mL) was added Compound 1 (1 g, 9.20 mmol) and dissolved in Nadmamp (1-dimethylamino-2-methyl-2-propoxy sodium). , 1.28 g, 9.20 mmol) was added and stirred for 12 hours. This solution was then filtered to remove the solvent under reduced pressure to give the title compound (0.70 g) as a white solid (yield: 40%).

¹ H NMR (C ₆ D ₆ , 300.13 MHz): δ 2.25 (s, 6 H, CH ₂ N (C H ₃ ) ₂ ), 2.20 (s, 2 HC H ₂ N), 1.26 (s, 6 H, C (C H ₃ ) ₂ ), 0.14 (s, 9 H, Si (C H ₃ ) ₃ ).

Elemental Analysis C ₉ H ₂₃ NOSi {calculated (calculated)}: C, 57.08 (40.82); H, 12.24 (9.44); N, 7.40 (5.86).

Hydrogen nuclear magnetic resonance ( ¹ H-NMR) spectra and Fourier transform infrared spectroscopy (FT-IR) spectra of the compounds are shown in FIGS. 1 and 2, respectively.

Example  2

Synthesis of di (methyl) -bis (1-dimethylamino-2-methyl-2-propoxy) silicon (IV) [Si (CH ₃ ) ₂ (dmamp) ₂ ]

To a 250 mL Schlenk flask containing tetrahydrofuran (150 mL) was added Compound 1 (1 g, 7.75 mmol) and dissolved in it. Nadmamp (1-dimethylamino-2-methyl-2-propoxy sodium) , 2.16 g, 15.49 mmol) was added and stirred for 12 hours. Subsequently, the solution was filtered to remove the solvent from the filtrate under reduced pressure to obtain a title compound (1.61 g) as a colorless liquid (yield: 71.4%) through distillation (70 ^° C / 10 ^-2 torr).

¹ H NMR (C ₆ D ₆ , 300.13 MHz): δ 2.28 (s, 12 H, CH ₂ N (C H ₃ ) ₂ ), 2.26 (s, 4 HC H ₂ N), 1.37 (s, 12 H, C (C H ₃ ) ₂ ), 0.26 (s, 6 H, Si (C H ₃ ) ₃ ).

¹³ C NMR (C ₆ D ₆ , 75.04 MHz): δ 76.19, 71.6, 48.3, 28.3, 2.47.

Elemental Analysis C ₁₄ H ₃₄ N ₂ O ₂ Si (calculated): C, 57.88 (56.67); H, 11.80 (12.89); N, 9.64 (9.77).

Hydrogen nuclear magnetic resonance ( ¹ H NMR) spectra, carbon nuclear magnetic resonance ( ¹³ C NMR) spectra, and Fourier transform infrared spectroscopy (FTIR) spectra of the compounds are shown in FIGS. 4 to 6, respectively.

Example  3

Synthesis of (methyl) -tri (1-dimethylamino-2-methyl-2-propoxy) silicon (IV) [Si (CH ₃ ) (dmamp) ₃ ]

In a 250 mL Schlenk flask containing tetrahydrofuran (150 mL) was added Compound 1 (1 g, 6.69 mmol) and dissolved in it, followed by Nadmamp (1-dimethylamino-2-methyl-2-propoxy sodium). , 2.79 g, 20.07 mmol) was added and stirred for 12 hours. Subsequently, the solution was filtered to remove the solvent under reduced pressure, and the title compound (1.38 g) as a colorless liquid was obtained through distillation (100 ^o C / 10 ^-2 torr) (yield: 52.5%).

¹ H NMR (C ₆ D ₆ , 300.13 MHz): δ 2.36 (s, 6 HC H ₂ N), 2.31 (s, 18 H, CH ₂ N (C H ₃ ) ₂ ), 1.48 (s, 18 H, C (C H ₃ ) ₂ ), 0.33 (s, 3 H, Si (C H ₃ ) ₃ ).

¹³ C NMR (C ₆ D ₆ , 75.04 MHz): δ 76.2, 71.6, 48.3, 28.3, 2.47.

Elemental Analysis C ₁₉ H ₄₅ N ₃ O ₃ Si (calculated): C, 58.26 (57.77); H, 11.58 (12.39); N, 10.73 (11.52).

Hydrogen nuclear magnetic resonance ( ¹ H NMR) spectra, carbon nuclear magnetic resonance ( ¹³ C NMR) spectra, and Fourier transform infrared spectroscopy (FTIR) spectra of the compounds are shown in FIGS. 8 to 10, respectively.

The thermogravimetric analysis (TGA) and differential thermal analysis (DTA) of each of the silicon compounds synthesized in Examples 1 to 3 are shown in FIGS. 3, 7 and 11.

Referring to FIG. 3, it was found that Si (CH ₃ ) ₃ (dmamp) of Example 1 rapidly volatilized two times near 116 ° C. and 141 ° C. to complete volatilization at around 212 ° C. and remained 19.55% of residue. Can be.

Referring to FIG. 7, it can be seen that Si (CH ₃ ) ₂ (dmamp) ₂ of Example 2 rapidly volatilized at about 100 ° C., and volatilization was completed at about 169 ° C., and a residue of 0% remained.

Referring to FIG. 11, it can be seen that Si (CH ₃ ) (dmamp) ₃ of Example 3 volatilizes rapidly at around 146 ° C., and volatilization is completed at around 226 ° C., and 2.03% of residue remains.

1 is a hydrogen atom magnetic resonance ( ¹ H NMR) spectrum of [Si (CH ₃ ) ₃ (dmamp)] according to Example 1 of the present invention.

2 is a Fourier transform infrared spectroscopy (FT-IR) spectrum of [Si (CH ₃ ) ₃ (dmamp)] according to Example 1 of the present invention.

3 is a thermogravimetric analysis (TGA) and differential thermal analysis (DTA) results of [Si (CH ₃ ) ₃ (dmamp)] according to Example 1 of the present invention.

4 is a hydrogen atom magnetic resonance ( ¹ H-NMR) spectrum of [Si (CH ₃ ) ₂ (dmamp) ₂ ] according to Example 2 of the present invention.

5 is a carbon atom magnetic resonance ( ¹³ C-NMR) spectrum of [Si (CH ₃ ) ₂ (dmamp) ₂ ] according to Example 2 of the present invention.

6 is a Fourier transform infrared spectroscopy (FT-IR) spectrum of [Si (CH ₃ ) ₂ (dmamp) ₂ ] according to Example 2 of the present invention.

7 is a thermogravimetric analysis and differential thermal analysis of [Si (CH ₃ ) ₂ (dmamp) ₂ ] according to Example 2 of the present invention.

8 is a hydrogen atom magnetic resonance ( ¹ H NMR) spectrum of [Si (CH ₃ ) (dmamp) ₃ ] according to Example 3 of the present invention.

9 is a carbon atom magnetic resonance ( ¹³ C-NMR) spectrum of [Si (CH ₃ ) (dmamp) ₃ ] according to Example 3 of the present invention.

10 is a Fourier transform infrared spectroscopy (FT-IR) spectrum of [Si (CH ₃ ) (dmamp) ₃ ] according to Example 3 of the present invention.

11 shows thermogravimetric and differential thermal analysis of [Si (CH ₃ ) (dmamp) ₃ ] according to Example 3 of the present invention.

Claims (8)

Silicone complex represented by the following formula (1). [Formula 1] SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m [In Formula 1, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are independently of each other a C ₁ -C ₇ linear or branched alkyl group; m and n are each independently an integer ranging from 1 to 3.] The method of claim 1, In Chemical Formula 1, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently an alkyl group selected from the group consisting of CH ₃ , C ₂ H ₅ and CH (CH ₃ ) ₂ . The method of claim 1, The silicone complex is tri (methyl)-(1-dimethylamino-2-methyl-2-propoxy) silicone (IV), di (methyl) -bis (1-dimethylamino-2-methyl-2-propoxy) A silicone complex comprising silicon (IV) or (methyl) -tri (1-dimethylamino-2-methyl-2-propoxy) silicon (IV). A process for producing a silicon complex compound of formula (1) comprising reacting a silicon compound of formula (2) with an alkali metal salt of formula (3). [Formula 1] SiR ¹ _m (OCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ ) _4-m [Formula 2] SiR ¹ _m Cl _4-m (3) MOCR ² R ³ (CH ₂ ) _n NR ⁴ R ⁵ [In Formula 1, Formula 2 and Formula 3, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are independently of each other a C ₁ -C ₇ linear or branched alkyl group; m and n are each independently an integer ranging from 1 to 3; M is hydrogen or an alkali metal.] The method of claim 4, wherein In Formula 3, wherein M is H, Li, Na or K method of producing a silicon complex. A method of growing a silicon thin film or a silicon oxide thin film using the silicon complex compound according to claim 1 as a precursor. The method of claim 6, The method of growing the thin film is a method of growing a silicon thin film or silicon oxide thin film, characterized in that by metal organic chemical vapor deposition (MOCVD). A silicon thin film or a silicon oxide thin film grown by the method of claim 6 or 7.

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