KR102283752B1 - Novel group iv transition metal compounds and preparation method thereof - Google Patents

Abstract

The present invention relates to a novel Group 4 transition metal compound and a method for preparing the same.

Description

Novel group 4 transition metal compound and method for preparing the same

The present invention relates to a novel Group 4 transition metal compound and a method for preparing the same.

In the semiconductor process, silicon oxide (SiO ₂ ) has been mainly used as a gate dielectric because the manufacturing process is relatively simple, but since it has a relatively low dielectric constant (k), when the thickness is thin, the leakage current from the gate to the channel ( gate-to-channel leakage current).

Accordingly, research into suitable alternative thin film materials and process technologies for providing very thin, reliable and low-defect gate dielectrics to improve device performance is being actively pursued.

In order to solve this problem, research on a high-k metal oxide material as a high-k material having excellent insulation, high dielectric constant, and low dielectric loss is being actively conducted.

As the semiconductor structure becomes more direct and miniaturized, it can be applied to various processes (e.g., atomic layer deposition (ALD), chemical vapor deposition (CVD)) with excellent step coverage even in fine patterns. As a high-k thin film material that can be used, the demand for a precursor compound having high thermal stability is increasing.

As an example of such a high-k thin film material, a Group 4 transition metal precursor has been proposed, and specifically, titanium-containing, zirconium-containing, and hafnium-containing precursors may be mentioned.

Prior art, see for example J. Mater. Chem., 1994, 4, 1815, a zirconium oxide thin film using a zirconium alkoxide precursor is known, and Zr(OtBu) ₄ is used as a precursor. However, Zr(OtBu) ₄ has a very short shelf life because it has a very high reactivity, so it is very difficult to handle in the thin film manufacturing process, and it causes a catalytic hydrolytic decomposition reaction even in a trace amount of moisture.

Also Chem. Mater., 2002, 14, 4350 discloses a zirconium oxide thin film formed of a zirconium compound coordinated with an amido ligand as a precursor. Zirconium amido compounds represented by Zr(NMeEt) ₄ or Zr(NEt ₂ ) ₄ all exist in a liquid state with low viscosity at room temperature, have a very high vapor pressure and easily remove amido ligands by ozone and water vapor. _{ZrO 2} using a layer deposition process is most widely used as a precursor for thin film production. However, these zirconium amido compounds are very reactive, so long-term storage is not easy. In particular, it has been recently known that they are decomposed during vaporization due to their low thermal stability, greatly affecting the quality of the thin film.

In addition, Group 4 transition metal precursors according to US 8471049 and the like are not thermally stable at high temperatures, and thus have low deposition rates and low deposition rates during chemical vapor deposition (CVD) and atomic layer deposition (ALD) processes. It had the disadvantage of having a growth rate.

Therefore, there is still a need for research on a precursor compound having superior properties compared to the precursor compound used as a conventional high-k thin film material.

US 8471049

J. Mater. Chem., 1994, 4, 1815 Chem. Mater., 2002, 14, 4350

An object of the present invention is to provide a novel Group 4 transition metal compound that can be used as a precursor for thin film production.

In addition, the present invention provides a method for preparing the Group 4 transition metal compound.

Another object of the present invention is to provide a method for preparing a Group 4 transition metal-containing thin film using the Group 4 transition metal compound.

In order to achieve the above object, the present invention provides a novel Group 4 transition metal compound, a Group 4 transition metal compound represented by the following formula (1).

[Formula 1]

In Formula 1,

M is a Group 4 transition metal;

R ¹ to R ⁵ are each independently a C1 to C10 linear or branched alkyl group;

n is 0 to 5;

In addition, the present invention provides a method for preparing a Group 4 transition metal compound of Formula 1 by reacting a compound of Formula 2 with a compound of Formula 3 below.

[Formula 1]

[Formula 2]

[Formula 3]

In Formulas 1 to 3,

M is a Group 4 transition metal;

R ¹ to R ⁵ are each independently a C1 to C10 linear or branched alkyl group;

n is 0 to 5;

In addition, the present invention provides a method for preparing a Group 4 transition metal-containing thin film using the Group 4 transition metal compound of Formula 1 above.

The Group 4 transition metal compound of the present invention has a novel structure including an aminoketone ligand, and can be used as a precursor to prepare a higher quality Group 4 transition metal-containing thin film, particularly a Group 4 transition metal oxide thin film.

In addition, the novel Group 4 transition metal compound according to the present invention exists as a solid or liquid at room temperature and has good handling properties.

That is, the Group 4 transition metal compound according to the present invention is a precursor material for a Group 4 transition metal-containing thin film such as a Group 4 transition metal oxide thin film and a Group 4 transition metal-containing particle such as a nano-sized Group 4 transition metal oxide. It is useful as a precursor.

Hereinafter, the present invention will be described in more detail. If there is no other definition in the technical and scientific terms used at this time, it has the meaning commonly understood by those of ordinary skill in the art to which this invention belongs, and may unnecessarily obscure the subject matter of the present invention in the following description. Descriptions of possible known functions and configurations will be omitted.

The present invention relates to a novel Group 4 transition metal compound that can be used as a precursor for preparing a nanomaterial containing a Group 4 transition metal-containing thin film, a Group 4 transition metal-containing nanoparticle and a Group 4 transition metal, and more specifically, It relates to a Group 4 transition metal compound represented by the formula (1).

[Formula 1]

In Formula 1,

M is a Group 4 transition metal;

R ¹ to R ⁵ are each independently a C1 to C10 linear or branched alkyl group;

n is an integer from 0 to 5;

The Group 4 transition metal compound of the present invention is a compound of a novel structure including an aminoketone ligand, and as a precursor for the preparation of a Group 4 transition metal-containing thin film, a Group 4 transition metal-containing nanoparticle and a nanomaterial containing a Group 4 transition metal. It can be useful. In particular, the Group 4 transition metal compound of Formula 1 is a precursor for preparing a Group 4 transition metal-containing thin film, and has high solubility in organic solvents widely used in semiconductor manufacturing processes, for example, benzene, tetrahydrofuran, toluene, chloroform, etc. Therefore, a high-quality group 4 transition metal-containing thin film can be manufactured using a known thin film manufacturing method.

In one embodiment of the present invention, M is titanium, zirconium or hafnium; R ¹ to R ⁵ are each independently a C1 to C7 linear or branched alkyl group; n may be an integer of 1 to 3, and preferably, R ¹ , R ² , R ⁴ and R ⁵ are each independently a C1 to C7 linear or branched alkyl group; R ³ may be a C3 to C7 branched alkyl group.

In one embodiment of the present invention, more preferably, M is zirconium or hafnium; R ¹ , R ² , R ⁴ and R ⁵ are each independently a C1 to C4 linear or branched alkyl group; R ³ is a C3 to C4 branched alkyl group; n may be an integer of 1 or 2.

Specifically, the R ¹ to R ⁵ are each independently methyl (methyl), ethyl (ethyl), propyl, isopropyl (iso-propyl), butyl (butyl), isobutyl (iso-butyl) or t -butyl (tert-butyl), more preferably R ¹ , R ² , R ⁴ and R ⁵ are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or t-butyl, R ³ may be isopropyl, isobutyl or t-butyl.

In addition, the present invention provides a method for preparing a Group 4 transition metal compound of Formula 1 above.

The Group 4 transition metal compound of Formula 1 may be prepared by reacting a compound represented by Formula 2 with a compound represented by Formula 3 below.

[Formula 2]

[Formula 3]

In Formulas 2 and 3,

M is a Group 4 transition metal;

R ¹ to R ⁵ are each independently a C1 to C10 linear or branched alkyl group;

n is an integer from 0 to 5;

In one embodiment of the present invention, the reaction may be carried out in an organic solvent, and the usable organic solvent is not limited, but it is preferable to use an organic solvent having high solubility for the reactants, more Preferably, hexane (Hexane), diethyl ether (diethylether), toluene (toluene), tetrahydrofuran (THF), etc. may be used, and more preferably, toluene may be used.

In an embodiment of the present invention, the Group 4 transition metal compound of Formula 1 is obtained by reacting the compound of Formula 2 and the compound of Formula 3 in an equivalence ratio of 1:2.0 to 2.5 at room temperature (rt) in an organic solvent. can be obtained in yield. At this time, after the above reaction, if necessary, you may purify by recrystallization or sublimation. In addition, the reaction may be carried out under an inert gas such as nitrogen.

In addition, the present invention provides a method for preparing a Group 4 transition metal-containing thin film using the Group 4 transition metal compound of Formula 1 above.

In an embodiment of the present invention, a thin film containing a Group 4 transition metal can be prepared through a known solution process or vacuum deposition using the Group 4 transition metal compound of Formula 1, and for example, Examples include chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), and atomic layer deposition (ALD).

Specifically, the Group 4 transition metal-containing thin film represents a Group 4 transition metal nitride thin film or a Group 4 transition metal oxide thin film.

The present invention provides a thin film prepared by the above method, and the thin film may be formed on various substrates. In this case, the substrate may be a metal substrate, an inorganic substrate, an organic-inorganic hybrid substrate, and the like, but is not limited thereto. Non-limiting examples of the metal substrate may be in the form of a foil, a sheet, a film, etc., copper (Cu), aluminum (Al), iron (Fe), silver (Ag) , palladium (Pd), nickel (Ni), chromium (Cr), molybdenum (Mo), tungsten (W), may be a metal substrate selected from the group consisting of stainless steel or alloys thereof, An example may be a graphite sheet, a carbon fabric, a glass fabric, a glass paper, a ceramic paper, a glass sheet, etc., -A non-limiting example of the inorganic hybrid substrate may be a polymer film containing inorganic particles, fiber reinforced plastic (FRP) manufactured by impregnating resin in glass fiber or carbon fiber, and the like.

The Group 4 transition metal compound of the present invention is a heteroleptic precursor to which ligands with different reactivity are introduced, that is, a precursor in which two kinds of ligands, namely amido and alkoxy, are combined. It has the advantage of compensating for disadvantages such as low reactivity and thermal stability of the introduced homoleptic precursor.

In addition, since the Group 4 transition metal compound of the present invention has a carbon-carbon double bond in the alkoxy ligand, it exhibits improved reactivity with ozone in the thin film deposition process, enabling thin film deposition under milder conditions.

The present invention may be better understood by the following examples, which are for illustrative purposes of the present invention and are not intended to limit the scope of protection defined by the appended claims.

At this time, unless there are other definitions in the technical terms and scientific terms used, those of ordinary skill in the art to which this invention belongs have the meanings commonly understood. In addition, repeated description of the same technical configuration and operation as in the prior art will be omitted.

Hereinafter, the synthesis of the Group 4 transition metal compound according to the present invention was performed under an inert argon or nitrogen atmosphere using a glove box or a Schlenk line. ^{The structure of the Group 4 transition metal compound obtained through 1} H and ¹³ C NMR spectrum (Bruker Advance 400 NMR) and elemental analysis (Thermo Scientific Flash 2000) was analyzed.

[Example 1] Preparation of zirconium compound Zr(OC( ^t Bu)=CHCH ₂ NMe ₂ ) ₂ (NMe ₂ ) ₂

After dissolving Tetrakis(dimethylamido)zirconium (1 g, 3.74 mmol) in toluene (50 mL), 1-(dimethylamino)-4,4-dimethylpentan-3-one (1 -(dimethylamino)-4,4-dimethylpentan-3-one) (1.17 g, 7.48 mmol) was added dropwise. After stirring at room temperature (25° C.) for 12 hours, toluene was removed under reduced pressure, and recrystallized from n-hexane to obtain the title compound Zr(OC( ^t Bu)=CHCH ₂ NMe ₂ ) ₂ (NMe ₂ ) ₂ as a white solid. (1.5 g, yield 81%).

¹ H NMR (400 MHz, C ₆ D ₆ ) δ 1.29 (s, 18H, 6C H ₃ ), 2.03 (s, 12H, 2N( CH ₃ ) ₂ ), 2.57 (s, 4H, 2NC H ₂ ), 3.27 (s, 12H, 2N ( C H 3) 2) 4.23 (t, 2H, 2CH 2 C H)

¹³ C NMR (400 MHz, C ₆ D ₆ ) δ 28.91, 36.46, 44.86, 47.85, 58.09, 88.77, 169.58

Elemental Analysis C ₂₂ H ₄₈ N ₄ O ₂ Zr - Calcd. (found): C, 53.72 (50.63); H, 9.84 (9.85); N, 11.39 (11.06)

[Example 2] Preparation of hafnium compound Hf(OC( ^t Bu)=CHCH ₂ NMe ₂ ) ₂ (NMe ₂ ) ₂

After dissolving Tetrakis(dimethylamido)hafnium (1 g, 2.82 mmol) in toluene (50 mL), 1-(dimethylamino)-4,4-dimethylpentan-3-one (1 -(dimethylamino)-4,4-dimethylpentan-3-one) (0.89 g, 5.64 mmol) was added dropwise. After stirring at room temperature (25° C.) for 12 hours, toluene was removed under reduced pressure, and recrystallized from n-hexane to obtain the title compound Hf (OC( ^t Bu)=CHCH ₂ NMe ₂ ) ₂ (NMe ₂ ) ₂ as a white solid. (1.3 g, yield 80%).

¹ H NMR (400 MHz, C ₆ D ₆ ) δ 1.28 (s, 18H, 6C H ₃ ), 2.05 (s, 12H, 2N( CH ₃ ) ₂ ), 2.56 (s, 4H, 2NC H ₂ ), 3.31 (s, 12H, 2N ( C H 3) 2) 4.20 (t, 2H, 2CH 2 C H)

¹³ C NMR (400 MHz, C ₆ D ₆ ) δ 28.90, 36.70, 44.89, 48.00, 57.96, 88.71, 169.36

Elemental analysis C ₂₂ H ₄₈ N ₄ O ₂ Hf - Calcd. (found): C, 45.63 (45.50); H, 8.36 (8.39); N, 9.67 (9.52)

Although the embodiments of the present invention have been described in detail as described above, those of ordinary skill in the art to which the present invention pertains, without departing from the spirit and scope of the present invention as defined in the appended claims The invention may be practiced with various modifications. Accordingly, modifications of future embodiments of the present invention will not depart from the technology of the present invention.

Claims (5)

delete A Group 4 transition metal compound represented by the following formula (1).
[Formula 1]

In Formula 1,
M is titanium, zirconium or hafnium;
R ¹ to R ⁵ are each independently a C1 to C7 linear or branched alkyl group;
n is an integer from 1 to 3. 3. The method of claim 2,
R ¹ , R ² , R ⁴ and R ⁵ are each independently a C1 to C7 linear or branched alkyl group;
R ³ is a C3 to C7 branched alkyl group, a Group 4 transition metal compound. A method for preparing a Group 4 transition metal compound of Formula 1 by reacting a compound of Formula 2 with a compound of Formula 3 below.
[Formula 1]

[Formula 2]

[Formula 3]

In Formulas 1 to 3,
M is titanium, zirconium or hafnium;
R ¹ to R ⁵ are each independently a C1 to C7 linear or branched alkyl group;
n is an integer from 1 to 3. A method for producing a thin film containing a Group 4 transition metal using the Group 4 transition metal compound according to any one of claims 2 and 3