KR102417216B1 - Group 4 organometallic precursor compound into which η6 borata benzene ligand is introduced, a method for manufacturing the same, and a method for forming a thin film using the same - Google Patents

Abstract

The present invention relates to a Group 4 organometallic precursor compound to which η ⁶ Borata benzene ligand is introduced, a method for preparing the precursor compound, and a method for forming a thin film using the precursor compound, wherein the method for forming a thin film according to the present invention comprises the precursor compound When used as a raw material, a thin film containing an oxide of a Group 4 transition metal can be formed with a uniform and thin thickness on a surface with a high aspect ratio by using metal organometallic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) at high temperature. In addition, by using the thin film for manufacturing a semiconductor DRAM, the recording density of the semiconductor DRAM can be improved.

Description

Group 4 organometallic precursor compound into which η6 borata benzene ligand is introduced, a method for manufacturing the same, and a method for forming a thin film using the precursor compound {Group 4 organometallic precursor compound into which η6 borata benzene ligand is introduced, a method for manufacturing the same, and a method for forming a thin film using the same}

The present invention relates to a zirconium organometallic precursor compound or hafnium organometallic precursor compound used in the manufacture of semiconductor devices, and more particularly, η ⁶ Borata benzene ligand, which has superior thermal stability compared to η ⁵ C _p series ligands. It relates to an organometallic precursor compound containing the introduced zirconium or hafnium, a method for preparing the organometallic precursor compound, and a method for forming a thin film using the same.

A precursor used in a semiconductor process generally refers to a precursor used to form a specific thin film (metal, metal oxide film, or metal nitride film). The precursor is generally an organometallic compound in which a central metal and a ligand are bound. Various ligands that can be used in the precursor are studied, representative examples of which are alkoxide, diene, β-diketonato, diazadiene, aryl, alkyl There is an amido group (alkylamido group) or cyclopentadiene (Cyclopentadiene).

The properties of the precursor may vary depending on the composition of the various ligands, and it has been reported in many literatures that the properties of the final thin film are affected due to the properties of the precursor. The properties required for the precursor include thermal stability, high volatility, high reactivity of surface, and high purity, and development of a precursor having the above properties is urgently required. .

Metal oxides such as ZrO ₂ , HfO ₂ , Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₅ , BaTiO ₃ , SrTiO ₃ , or (Ba, Sr)TiO ₃ are used as materials recently applied to DRAM capacitors. , the metal oxide has a higher dielectric constant (high-k) than silicon oxide (SiO ₂ ), and has been applied to high-integration and high-capacity memory semiconductors.

For example, a metal oxide having a high dielectric constant is thin, uniform, and has excellent thin film properties, and in order to obtain excellent step coverage properties in a structure having a high aspect ratio (MOCVD) and atomic Used in layer deposition (ALD) processes. For a more detailed example, for the formation of a zirconia (ZrO ₂ ) thin film, tetrakisethylmethylamino zirconium (Zr(NMeEt) ₄ ; TEMAZ) is used as a precursor.

However, TEMAZ is a liquid at room temperature and a compound having a high vapor pressure, but has a low thermal stability, so step coverage is lowered and this generates a leakage current. Not suitable for use on the device.

Recently, as a cyclopentadiene (Cp) ligand, which is often used in metallocene catalyst compounds, was introduced as an alternative compound, the thermal stability of the precursor was dramatically increased. Among Cp-type precursors, RCpZr[N(CH ₃ ) ₂ ] ₃ (R=H, Methyl, Ethyl), [CH ₃ Cp] ₂ Zr(CH ₃ ) ₂ , (CH ₃ Cp) ₂ ZrCH ₃ OCH ₃ , Cp ₂ Zr(CH ₃ ) ₂ or RCpZr(CHIT) (CHIT = Cycloheptatrienyl) has been developed as an ALD precursor for forming ZrO ₂ with a thickness of about several tens of nm.

Cyclopentadienyl trisdiamido zirconium [RCpZr[N(CH ₃ ) ₂ ] ₃ (R=H): CpTDMAZ] compound as a Cp-type applied in the current semiconductor process is used as a precursor in the ALD process. This compound is a liquid at room temperature and has a high vapor pressure. Compared to Tetrakis-Ethyl-methyl-Amino-zirconium (TEMAZr), it is stable at a high deposition temperature, and thus ALD process. can be easily applied to However, this compound has a problem in that side reactants are generated in the ALD process.

Meanwhile, currently widely used hafnium precursors include HfCl ₄ , Cp ₂ HfCl ₂ , HfI ₄ , tetrakis(dimethylamino)hafnium(TDMAH), or tetrakis(ethylmethylamino)hafnium(TEMAH), but HfCl ₄ has a high vapor pressure and Carbon- It is mainly used because of its free structure. In previous studies, HfO ₂ has a high dielectric constant (21 to 23) and low leakage current (about 10-7 to 10-9 _A /cm ² ), but chlorine (Cl) atoms from the precursor during the deposition process There is a problem of accumulation at the grain boundary. In addition, it acts as a factor to degrade the performance of the electric device, such as increasing the leakage current by forming a void (void) in a high temperature condition. To solve this problem, HfO ₂ deposition using Cp ₂ HfCl ₂ containing less Cl than HfCl ₄ has been studied, but it is confirmed that chlorine contamination is still present in HfO ₂ .

Therefore, there is a demand in the semiconductor industry for a novel organic zirconium raw material compound or hafnium raw material compound that has higher thermal stability and volatility than TEMAZ, CpTDMAZ or TDMAH, and does not decompose even when stored for a long time at high temperature.

1. Republic of Korea Patent Publication No. 10-2009-0103121 2. Republic of Korea Patent Publication No. 10-2012-0038369

The present invention is an organometal containing zirconium or hafnium into which η ⁶ borata benzene ligand having higher thermal stability and step coverage than TEMAZ, CpTDMAZ or TDMAH in order to solve the problems in the prior art as described above. A precursor compound is provided, and the precursor compound does not decompose even when stored for a long time at a high temperature.

In addition, the present invention is an organometallic precursor compound containing zirconium or hafnium into which η ⁶ borata benzene ligand having high thermal stability and volatility by applying an organometallic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) process, An object of the present invention is to provide a method for manufacturing the same and a method for forming a thin film using the same.

In order to solve the above problems, the present invention provides a group 4 organometallic precursor compound into which a novel η ⁶ borata benzene ligand represented by the following formula (1) is introduced, a method for preparing the same, and a method for forming a thin film using the same.

In the present invention, the organometallic precursor compound containing zirconium or hafnium into which η ⁶ borata benzene ligand is introduced may be represented by the following formula (1).

[Formula 1]

In Formula 1,

M is Zr or Hf,

R ₁ and R ₂ may each independently be hydrogen, a C ₁ -C ₁₀ alkyl group, or a silylamine group.

In addition, in the present invention, among the organometallic precursor compounds represented by Formula 1, R ₁ to R ₂ is a methyl group η ⁶ Borata benzene ligand is introduced into the organometallic precursor compound containing zirconium or hafnium is represented by the following Formula 2 can

[Formula 2]

In Formula 2,

M may be Zr or Hf.

In addition, in the present invention, among the organometallic precursor compounds represented by Formula 1, R ₁ to R ₂ are ethyl groups η ⁶ Borata benzene ligand is introduced into the organometallic precursor compound containing zirconium or hafnium is represented by the following Formula 3 can

[Formula 3]

In Formula 3,

M may be Zr or Hf.

In addition, in the present invention, among the organometallic precursor compounds represented by Chemical Formula 1, R ₁ is a methyl group and R ₂ is an ethyl group η ⁶ An organometallic precursor compound containing zirconium or hafnium into which a benzene ligand is introduced is represented by the following Chemical Formula 4 can be expressed

[Formula 4]

In Formula 4,

M may be Zr or Hf.

In addition, in the present invention, the organometallic precursor compound containing zirconium or hafnium into which the η ⁶ borata benzene ligand is introduced can be prepared by the following method.

[Scheme 1]

In Scheme 1,

M is Zr or Hf,

R ₁ to R ₂ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a silylamine group,

L may be triethylamine (Triethylamine), pyridine (Pyridine) or trimethylphosphine (Trimethylphosphane).

In addition, in the present invention, the organic solvent used in Scheme 1 may be zirconium or hafnium into which η ⁶ Borata benzene ligand, which is hexane or toluene, is introduced.

In addition, in the present invention, the organometallic precursor compound according to Chemical Formulas 1 to 4 and the precursor composition including the organic compound may be used to perform organic metal chemical vapor deposition (MOCVD) or atomic layer deposition (ALD).

In addition, in the present invention, the organic compound is a non-polar solvent having 5 to 10 carbon atoms such as pentane, hexane, heptane, octane or cyclohexane, a polar solvent containing oxygen such as diethyl ether, dimethoxyethane or THF and benzene, It may be one or more solvents selected from the group consisting of aromatic solvents having 6 to 10 carbon atoms, such as toluene or xylene.

In addition, in the present invention, the precursor composition may be 0 to 50% by weight based on the organic compound.

In addition, in the present invention, a bubbling method, a vapor phase, a mass flow controller (MFC), a direct liquid injection (DLI), or a precursor as a delivery method for moving the precursor composition on a substrate It can be carried out by a liquid transport method in which the compound is dissolved in an organic solvent and transported.

Accordingly, when the thin film is deposited on the substrate using the precursor compound according to an embodiment of the present invention, the quality of the thin film deposited on the substrate is improved.

As described above, the method for forming a thin film using the Group 4 organometallic precursor compound into which the η ⁶ Borata benzene ligand is introduced according to the present invention is performed at a high temperature using an organometallic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) method. A thin film having a uniform and thin thickness can be implemented on a surface with a high aspect ratio.

However, the effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

Figure 1 is CpHf (NMe ₂ ) ₃ and A graph showing the results of thermogravimetic analysis (TGA) of the organometallic precursor compound prepared according to an embodiment of the present invention ([Me ₂ N·BC ₅ H ₅ ]Hf(NMe ₂ ) ₃ ).
Figure 2 is CpHf (NMe ₂ ) ₃ and An embodiment of the present invention ([Me ₂ N·BC ₅ H ₅ ]Hf(NMe ₂ ) ₃ ) A graph showing the results of differential thermal analysis (DTA) of the organometallic precursor compound prepared according to the present invention.
3 is a graph showing the thickness and GPC of the thin film according to the deposition temperature of the organometallic precursor compound prepared according to an embodiment of the present invention ([Me ₂ N·BC ₅ H ₅ ]Hf(NMe ₂ ) ₃ ) .

The present invention relates to a precursor compound, a method for preparing the same, and a method for forming a thin film using the same. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described below.

With the development of electronic technology, demands for miniaturization, low power consumption, and high capacity of electronic devices used in various electronic devices are rapidly increasing. The organometallic oxide for manufacturing an electronic device includes hafnium oxide (HfO ₂ ), zirconium oxide (ZrO ₂ ), or titanium oxide (TiO ₂ ). The most preferred organometallic oxide is hafnium oxide. Hafnium oxide exhibits excellent temperature stability, and has advantages of chemical stability and high dielectric constant.

In general, when forming a thin film using the organic metal oxide as a precursor, chemical vapor deposition (CVD) or atomic layer deposition (ALD, Atomic Layer Deposition) typified by Metal Organic Chemical Vapor Deposition (MOCVD) Thin film deposition is performed through a chemical deposition process such as

As a pulse cycle proceeds in the ALD process, as an example of an organometallic precursor, a metal alkyl amide may be injected in a pure form. Suitable metal alkyl amides include mixtures forming the structure:

M(NR ¹ R ² )n

wherein M is a Group 4 metal comprising hafnium, zirconium or titanium, R ¹ and R ² are selected from the group comprising substituted or unsubstituted linear, branched and cyclic alkyl, and n is 4 . Preferably R ¹ and R ² are each C ₁ -C ₆ alkyl such as methyl or ethyl, these ligands reducing carbon contamination in the final film. More preferably, NR ¹ R ² is ethyl methyl amide. The use of a metal alkyl amide with ethyl methyl amide as a ligand results in less carbon contamination in the metal oxide film. For example, hafnium tetraethylmethyl amide (Hf-TEMA) can generate less carbon pollution than closely related mixtures such as hafnium tetramethyl amide and hafnium tetra ethyl amide.

Meanwhile, recently, a cyclopentadienyl tris(dimethylamino)zirconium (Cyclopentadienyl Tris(dimethylamino)Zirconium, CpZr(NMe ₂ ) ₃ , ZAC) compound is most widely used as a precursor for forming a zirconium-based thin film such as zirconia. . This compound is a liquid with low viscosity at room temperature, and has excellent storage stability compared to zirconium organic compounds bound with amine ligands, and has excellent thermal stability and high vapor pressure. have. However, when this compound is applied to ALD, there is a problem in that a reaction by-product is generated.

In addition, as a raw material for a hafnium oxide thin film or hafnium-containing composite oxide thin film by the ALD method, HfCl ₄ , Hf(acac) ₄ (acac=acetylacetonate), Hf(tmhd) ₄ (tmhd=2, 2, 6, 6 -tetramethyl-3, 5-heptanediionate) or Hf(OtBy) ₄ (tBu=tert-butyl) is used, in addition to the tetrakisamite complex Hf(NRR′)4 (R and R′ are methyl groups or an ethyl group) may be used.

Among the above raw materials, HfCl ₄ has low volatility and requires a high temperature to form an oxide film, so it is unsuitable as a raw material for forming a thin film used in a semiconductor device. HfCl(tmhd) ₃ or HfCl ₂ (tmhd) ₂ containing chlorine atoms has also been studied, but their vaporization temperature is high, and this is not satisfactory.

An example in which a hafnium oxide thin film was formed by the ALD method using the tetrakisamide complex Hf(NRR') ₄ as a raw material has been reported. However, the tetrakisamide complex has low thermal stability, for example, tetrakis(dimethylamido)hafnium [Hf(NMe ₂ ) ₄ ] at 90° C., tetrakis(ethylmethylamido)hafnium [Hf(NMeEt) ) ₄ ] can be decomposed slowly at 140°C. In Korean Patent Application Laid-Open No. 10-2008-0031835, Hf(NmeEt) ₄ was heated at 150° C. for 120 hours to investigate thermal stability, and it was confirmed that 78% of Hf(NMeEt) ₄ was decomposed. That is, it is difficult to say that these tetrakisamide complexes have sufficient thermal stability as industrial raw materials for thin film formation.

Therefore, the present invention provides a precursor material capable of depositing a thin film at a high temperature due to excellent thermal stability, improving the step coverage of the formed thin film, stably atomic layer deposition, and securing a wide ALD window. would like to provide

Hereinafter, embodiments of the present invention have been described in detail, but the present application may not be limited thereto.

The Group 4 organometallic-containing precursor compound into which the η ⁶ Borata benzene ligand is introduced according to an embodiment of the present invention may be prepared by the method represented by Scheme 1 below.

[Scheme 1]

In Scheme 1, M is selected from Zr and Hf, R ₁ to R ₂ are the same or different, respectively, hydrogen or an alkyl group having 1 to 5 carbon atoms or a silylamine group, and L is triethylamine ), pyridine (Pyrridine) or trimethylphosphine (Trimethylphosphane). In addition, the organic solvent may be selected from benzene, hexane, and toluene.

The Group 4 organometallic-containing precursor compound into which the η ⁶ borata benzene ligand prepared in Scheme 1 is introduced is a compound represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1, M is selected from metal elements belonging to groups 4A and 4B on the periodic table, and R ₁ to R ₂ are each independently hydrogen, a linear or branched alkyl group having 1 to 5 carbon atoms, or a silylamine group. .

A more preferred example of the precursor compound used in the present invention is an organometallic compound in which M in Formula 1 is Zr or Hf, and R ₁ and R ₂ are both a methyl group (—CH ₃ ), and is represented by Formula 2 below.

[Formula 2]

As a non-polar organic solvent used for synthesizing the organometallic precursor compound represented by the above [Formula 2], pentane, hexane, heptane, benzene or toluene may be used, and in order to suppress the decomposition reaction due to moisture during the reaction The reaction may proceed under a nitrogen (N ₂ ) or argon (Ar) stream.

The precursor composition for forming a thin film of the present invention may be prepared by uniformly mixing the organometallic precursor compound according to Formula 1 and the organic compound. Here, that the organometallic precursor compound and the organic compound are uniformly mixed means that the concentrations of the organometallic precursor compound and the organic compound are substantially the same in the entire region of the composition.

The organic compound may be a non-polar organic compound, an aromatic organic compound, or an electron-donating organic compound, alone or in combination.

As the non-polar organic compound, an aliphatic hydrocarbon compound having 5 to 10 carbon atoms, preferably a linear, branched or cyclo alkane compound having 5 to 10 carbon atoms, may be used. Specific examples of the non-polar organic compound may include hexane, heptane, octane, cyclohexane, neopentane, or a mixture thereof.

As the aromatic organic compound, an aromatic hydrocarbon compound having 6 to 10 carbon atoms may be used. Specific examples of the aromatic organic compound include benzene, toluene, xylene, and mixtures thereof.

Examples of the electron-donating organic compound include an alkylamine compound having 2 to 12 carbon atoms, an alkylallyl compound having 3 to 12 carbon atoms, a heterocyclic compound containing oxygen and/or nitrogen, an ether compound having 2 to 10 carbon atoms, mixtures thereof and the like can be used. More specifically, as the alkylamine compound having 2 to 12 carbon atoms, secondary or tertiary amines having 2 to 12 carbon atoms may be used. Specific examples of the secondary amine include dimethylamine, diethylamine, ethylmethylamine, diisopropylamine, and the like, and specific examples of the tertiary amine include ethyldimethylamine, methyldiethylamine, and triethylamine. , tributyl, and tetramethylethylenediamine can be exemplified.

Such an organic compound improves the thermal stability and storage stability of the precursor compound and lowers the viscosity during the storage and transport of the organometallic precursor compound represented by Formula 1 above. In addition, the organic compound serves to be uniformly deposited on the substrate after vaporization at a temperature similar to that of the organometallic precursor compound.

When the organic compound is mixed with the organometallic precursor compound represented by Chemical Formula 1, the dispersibility thereof is excellent and the vaporization temperature is similar, so that the η ⁶ borata benzene ligand is introduced into the group 4 organometallic-containing precursor compound Physical properties can be improved

The amount of the organic compound used is 0.1 to 10 moles, preferably 0.2 to 5 moles, more preferably based on 1 mole of the Group 4 organometallic-containing precursor compound into which the η ⁶ Borata benzene ligand represented by Formula 1 is introduced. Preferably 0.5 to 3 moles. Here, if the amount of the organic compound used is too small, the thermal stability of the precursor composition for forming a thin film may be insufficient or the viscosity may not be sufficiently decreased. There is a possibility that deposition efficiency may be lowered, such as time and energy required.

In the method for depositing a thin film using an organometallic precursor compound according to an embodiment of the present invention, a deposition process for forming a thin film is not particularly limited. Chemical vapor deposition and other physical vapor deposition (PVD) may be used, preferably chemical vapor deposition (CVD) such as metal organic chemical vapor deposition (MOCVD), low pressure CVD (LPCVD) plasma enhanced chemical vapor deposition ( Plasma Enhanced Chemical Vapor Deposition (PECVD), pulsed PECVD, atomic layer deposition (ALD), plasma enhanced atomic layer deposition (PEALD), and combinations thereof may be used.

Since the organometallic precursor compound according to an embodiment of the present invention has excellent thermal stability, a thin film of good quality can be formed at a low temperature as well as a high temperature deposition process such as metal organic chemical vapor deposition (MOCVD). In addition, a single atomic layer can be uniformly grown according to a self-limiting reaction in the atomic layer deposition (ALD) process. In addition, since the precursor compound according to an embodiment of the present invention has almost no residue even at a high temperature of about 500° C. or higher, there is an advantage in that the temperature of the evaporator can be increased during the thin film deposition process.

In the thin film deposition method of the present invention, the deposition temperature at which the organic metal precursor composition according to an embodiment of the present invention is deposited on a substrate may be in a temperature range of 50 to 500°C. The temperature range of the deposition temperature may be preferably 50 to 250 °C, more preferably 50 to 100 °C. In addition, the internal pressure of the process chamber in which the deposition reaction is performed may be maintained at 0.2 to 10 torr.

In the method of depositing a thin film using the organometallic precursor composition according to an embodiment of the present invention, if necessary for the process, the step of transferring the organometallic precursor composition onto the substrate before deposition may be preceded. Methods of transferring the organometallic precursor composition onto the substrate include a bubbling method, a vapor phase MFC (Mass Flow controller), a direct gas injection method (DGI, Direct Gas Injection), and a direct liquid injection method ( One or more types may be selected from DLI, Direct Liquid Injection) or an organic solution supply method in which an organometallic precursor composition is dissolved in an appropriate organic solvent and transferred.

In the organic solution supply method, suitable organic solvents may include ethylbenzene, mesitylene, decane or dodecane.

In the bubbling method or the direct gas injection method, the organometallic precursor composition may be moved onto the substrate together with an appropriate carrier gas, and a gas that does not react with the organometallic precursor composition according to an embodiment of the present invention may be used as the carrier gas. have. The carrier gas may include a gas composed of argon (Ar), nitrogen (N ₂ ), helium (He), hydrogen (H ₂ ), and combinations thereof.

In addition, in addition to the carrier gas, a reactive gas may be supplied onto the substrate together with the organometallic precursor composition according to an embodiment of the present invention. Examples of the reactive gas may include an oxygen source or a nitrogen source, silane (SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , etc.) or alkylsilane having a silane bond (SiH ₂ Me ₂ , SiH ₂ Et ₂ , etc.) or amino silane (N(SiH ₃ ) ₃ ) or mixtures thereof.

The method for depositing a thin film of the present invention, in particular, a specific method for performing atomic layer deposition (ALD) using the precursor composition according to an embodiment of the present invention is as follows. i) transferring the precursor composition to the chamber ii) adsorbing the transferred precursor composition onto the substrate to form a precursor layer on the substrate iii) injecting a first purge gas into the chamber to remove excess zirconium or hafnium precursor The removal step, iv) injecting a reaction gas into the chamber to form a zirconium oxide film or a hafnium oxide film, and v) injecting a second purge gas into the chamber to remove excess reaction gas and by-products are one cycle, , 10 to 1000 times, preferably 100 to 600 cycles can be repeated. An inert gas such as argon may be used as the first purge gas and the second purge gas.

Hereinafter, the present invention will be described in detail by way of Examples. However, the following examples are merely illustrative of the present invention, and the content of the present invention is not limited by the following examples.

Prerequisites for the experiment

The technique for synthesizing the organometallic compound in the present invention used the standard pore line Schlenk technique, and the synthesis of all materials was performed under a nitrogen atmosphere. Hexane and borabenzyl pyridine used in Examples of the present invention were manufactured by Aldrich. All solvents were stirred with CaH ₂ for one day before use to completely remove residual moisture, and then used after fractionation. TDMAHf([Tetrakis(dimethylamino) hafnium] and TDMAZr([Tetrakis(dimethylamino) Zirconium]) were manufactured by Aldrich. CpHf(DMA) ₃ was manufactured by Soulbrain. Quantification of the material was carried out in a glove box. .

To analyze the structure of the compound, a JEOL JNM-ECS 400 Hz NMR spectrometer ( ¹ H-NMR 400 MHz) was used. The solvent benzene-d ₆ (C ₆ D ₆ ) used for NMR analysis was used after completely removing residual moisture by stirring with CaH ₂ for one day. The thermal stability and decomposition temperature of the compound were analyzed using TA-Q 600, and the sample amount was 10 mg.

The result of ¹ H-NMR is expressed as a chemical shift (δ), which measures the difference in how much the position of the resonance absorption line differs from that of the reference material due to the structural difference of the sample to relatively confirm the position of the absorption line of the sample. is used as a measure of As a representative reference material, Tetra-methyl silane is the most used.

The chemical shift (δ) is recorded in units of parts per million (PPM), means the ratio of the frequency (Hz) shifted from the TMS to the total device frequency (Hz), and is expressed as δ (delta scale) .

[Example]

<Example 1> [Me ₂ NBC ₅ H ₅ ]Hf(NMe ₂ ) ₃ manufacture of

After quantifying 20 g (56.3 mmol) of TDMAHf ([Tetrakis(dimethylamino) hafnium] in a flame-dried 500 mL Schlenk flask), it was diluted by dissolving it in 150 mL of hexane and then maintained at -10 °C. To a flask maintained at -10 ° C, 8.84 g (57 mmol) of borabenzyl pyridine was slowly added dropwise to prepare a mixture, and the mixture was stirred for 4 hours at 25 ° C. When the reaction was completed, all the solvents in the solution were removed under reduced pressure. After removal, the remaining viscous orange liquid was distilled under reduced pressure to obtain an orange liquid compound [Me ₂ N·BC ₅ H ₅ ]Hf(NMe ₂ ) ₃ .

Yield: 20.9 g (86%);

Boiling Point (b.p): 130° C., 0.56 torr;

¹ H-NMR (400 MHz, C ₆ D ₆ , 25° C.): δ 2.75(s, 6H, BN( CH ₃ ) ₂ ),

δ 2.96(s, 18H, Hf[N (CH ₃ ) ₂ ] ₃ ),

δ 5.64 (tt, 1H, CH CHCHB),

δ 5.74 (dd, 2H, CHCH CH B),

δ 7.05 (dd, 2H, CH CH CHB),

<Example 2> [Me ₂ NBC ₅ H ₅ ]Zr(NMe ₂ ) ₃ manufacture of

After quantifying 20 g (74.7 mmol) of TDMAZr ([Tetrakis(dimethylamino) Zirconium] in a flame-dried 500 mL Schlenk flask), it was diluted by dissolving it in 150 mL of hexane and then maintained at -10°C. To a flask maintained at -10 ° C, 12.7 g (82.2 mmol) of borabenzyl pyridine was slowly added dropwise to prepare a mixture, and the mixture was stirred for 4 hours at 25 ° C. When the reaction was completed, the solvent in the solution was removed under reduced pressure. After removing all, the remaining viscous orange liquid was distilled under reduced pressure to obtain an orange liquid compound [Me ₂ N·BC ₅ H ₅ ]Zr(NMe ₂ ) ₃ .

Yield: 21.5 g (84%);

Boiling Point (b.p): 126° C., 0.54 torr;

¹ H-NMR (400 MHz, C ₆ D ₆ , 25° C.): δ 2.76(s, 6H, BN( CH ₃ ) ₂ ),

δ 2.91(s, 18H, Hf[N (CH ₃ ) ₂ ] ₃ ),

δ 5.66 (tt, 1H, CH CHCHB),

δ 5.76 (dd, 2H, CHCH CH B),

δ 7.06 (dd, 2H, CH CH CHB),

<Example 3> Thermal analysis of compounds and precursor compositions

CpHf (DMA) ₃ and the borata benzene compound prepared in Example 1 and thermogravimetic analysis (TGA) and differential thermal analysis (DTA, differential thermal analysis) to determine the thermal properties of the precursor composition containing the same Analysis was performed. For material analysis, transport gas argon (Ar), transport gas flow rate 100 cc/min, temperature increase rate 10° C./min, and temperature range were set to 30 to 500° C. (confirmed). The results of the DTA analysis according to this experiment are shown in FIG. 2 . In FIG. 1 , the green curve represents the TGA analysis result, and in FIG. 2 , the blue curve represents the DTA analysis result.

As can be seen from the graph analysis result of FIG. 1 , the temperatures at which 50% of the mass of the organometallic compound and the precursor composition for forming a thin film including the same are decomposed are 181.3 and 231.7° C., respectively. Therefore, it can be seen that the temperature at which 50% of the mass of the precursor composition for forming a thin film including the same according to an embodiment of the present invention is high is high, so that the thermal stability is relatively high. can be deposited and formed.

On the other hand, as a result of checking the residue remaining after the temperature was raised to 499° C., it was confirmed that the residues of the organometallic compound and the precursor composition for forming a thin film including the same were 0.11 and 1.83%, respectively. The generation of these residues is a factor that greatly affects the flame retardancy and improves the thermal stability of the material. Excellent thermal stability of the precursor composition for forming a thin film according to an embodiment of the present invention was confirmed. Therefore, since the residue of the precursor composition for forming a thin film according to an embodiment of the present invention is small, storage stability is increased, and the temperature of a vaporizer can be increased, so that a thin film having good film properties can be deposited. have.

In FIG. 2, a differential thermal analysis (DTA) analysis graph of CpHf (DMA) ₃ and the borata benzene compound prepared in Example 1 is shown. From the number, shape, and location of the peaks in the DTA graph, the type or properties of the sample can be identified, and the width of the peak corresponds to the change in enthalpy, so quantitative measurement of the heat of reaction is also possible.

2, the graph on the left and the graph on the right are graphs using CpHf (DMA) ₃ and Example 1, respectively. In the graph, it can be seen that the start of the peak indicates that the reaction starts at the time when the denaturation of the corresponding material occurs. First, in the graph on the left, the first peak appears at 198.7° C., and it can be seen that crystallization occurs at the corresponding peak time. The second peak appears at 213.3° C. and it can be seen that melting occurs at the corresponding peak point. The third peak appears at 413.5° C., and it can be seen that oxidation occurs at the corresponding peak point. The temperature at which the peak returns to its original state means that the phenomenon of material denaturation ends, and therefore, in the case of the left graph, it can be seen that the material is stabilized at 450°C.

On the other hand, in the case of the right graph of FIG. 2 , the temperature at which the first peak occurs is 238.1° C., and the temperature at which the second peak occurs is 262.6° C. It can be seen that peaks occur at higher temperatures with respect to the graph on the left.

In addition, since the area of the peak in the graph represents the change in enthalpy, it is possible to quantitatively measure the heat of reaction. In the graph on the left, the area of the peak is -159.177 K's, and in the graph on the right, the area of the peak is -129.814 K's. Therefore, in the case of CpHf(DMA) ₃ , the enthalpy change is relatively large compared to that of borata benzene when heat is applied. It can be seen that the thermal stability is low.

<Example 4> Thin film thickness and GPC according to temperature

[Me ₂ N·BC ₅ H ₅ ]Hf(NMe ₂ ) ₃ obtained in Example 1 was used as a precursor to form an organometallic oxide layer using an atomic layer deposition (ALD) experiment. In this case, a silicon (Si) wafer was used as the substrate. The substrate was heated to 300°C to 350°C. In addition, the precursor compound contained in a container made of stainless steel was heated to a temperature of 150° C., and argon (Ar) gas at a flow rate of 50 sccm was passed through the container to supply the precursor compound to an ALD reactor for atomic layer deposition. . The internal pressure of the ALD reactor was maintained at 3 torr. The precursor compound gas was supplied to the ALD reactor for 5 seconds, and then argon gas was supplied for 10 seconds. After that, ozone (O ₃ ) gas was supplied for 5 seconds, and argon gas was supplied again for 10 seconds to complete ALD 1 cycle, and this was repeated 500 times. The chamber temperature was carried out at 150-350 °C, and the results are shown in Table 1.

Film thickness and GPC as a function of temperature Dep.temp.(℃) Thickness(nm) Growth rate (nm/cycle) 150 13 0.026 200 17 0.034 250 27 0.054 300 33 0.066 350 31 0.062

3 is an organic metal oxide film formed using an atomic layer deposition method (ALD) using [Me ₂ N·BC ₅ H ₅ ]Hf(NMe ₂ ) ₃ obtained in Example 1 as a precursor according to temperature and The result graph of thin film growth rate cycle (GPC) is shown.

Referring to FIG. 3 , it can be seen that as the temperature of the chamber increases, the thickness and thin film growth rate increase in proportion to the temperature example. When the chamber temperature is 300℃, the growth rate of the thin film is the largest, and the thickness of the thin film is also the thickest, and at this point, the equipment use time is the shortest and the productivity is good.

The description of the present invention described above is for illustration, and those of ordinary skill in the art to which this application belongs will understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. . Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and likewise components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are interpreted as being included in the scope of the present invention. should be

Claims (10)

delete delete delete delete A method for preparing an organometallic precursor compound containing zirconium or hafnium into which η ⁶ borata benzene ligand is introduced as represented by the following Reaction Scheme 1:
[Scheme 1]

In Scheme 1,
M is Zr or Hf,
R ₁ to R ₂ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a silylamine group,
L is triethylamine, pyridine, or trimethylphosphane. 6. The method of claim 5,
The organic solvent used in Scheme 1 is hexane (hexane) or toluene (toluene) η ⁶ Borata benzene ligand is introduced a method of producing an organometallic precursor compound containing zirconium or hafnium. Using a precursor composition comprising an organometallic precursor compound and an organic compound prepared by the manufacturing method according to any one of claims 5 to 6, organometallic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD) A method for forming a thin film, characterized in that performed by 8. The method of claim 7,
The organic compound is a non-polar solvent having 5 to 10 carbon atoms such as pentane, hexane, heptane, octane or cyclohexane, a polar solvent containing oxygen such as diethyl ether, dimethoxyethane or THF, benzene, toluene or xylene, etc. A method for forming a thin film comprising at least one solvent selected from the group consisting of aromatic solvents having 6 to 10 carbon atoms. 8. The method of claim 7 .
A method for forming a thin film, characterized in that 0 to 50% by weight of the organic compound with respect to the precursor composition. 8. The method of claim 7 .
The delivery method of moving the precursor composition on the substrate is a bubbling method, a vapor phase, a mass flow controller (MFC), direct liquid injection (DLI), or a precursor compound in an organic solvent. A method for forming a thin film, characterized in that it is carried out by a liquid transfer method for dissolving and transferring.

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