KR20220158601A - Metal precursor compound for forming semiconductor film and metal-containing film prepared by using the same - Google Patents

Abstract

The present invention relates to a metal precursor compound for forming a semiconductor thin film represented by formula 1, and a metal-containing thin film formed by using the same. According to the present invention, in the formula 1 of the metal precursor compound for forming a semiconductor thin film, each of R1 to R6 is independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and each of n and m is independently an integer of 1 to 5. The purpose of the present invention is to provide the metal precursor compound for forming a semiconductor thin film which can form a semiconductor metal-containing thin film representing a high dielectric constant (high-K) characteristic.

Description

Metal precursor compound for forming semiconductor thin film and metal-containing thin film manufactured using it

The present invention relates to a metal precursor compound for forming a semiconductor thin film and a metal-containing thin film manufactured using the metal precursor compound.

Since chemical vapor deposition (CVD) and atomic layer deposition (ALD) can achieve conformal thin films (metal, oxide, nitride, etc.) through fine tuning of parameters, thin film growth and/or Or it has been applied as a deposition process technology.

In particular, since thin film growth and/or deposition processes are mainly controlled by chemical reactions of metal-organic compounds (precursors), it is important to develop optimal precursors by predicting properties and reaction processes of these compounds. Therefore, the development of efficient precursors to obtain specific properties according to specific types of thin films is ongoing.

However, in that conventional precursors are solid materials or low-purity materials, there is a limit to improving the crystallinity and properties of thin films due to limitations in physical properties and quality. That is, when the precursor is a solid material, there is a problem in reproducibility in the process, and when the precursor is a low-purity material, deterioration in dielectric constant and leakage current characteristics due to impurities causes deterioration in thin film properties. Moreover, in the case of the conventional low-purity material, when the low-purity material is applied according to the miniaturization of the semiconductor process, the influence of impurities is further increased, thereby accelerating the deterioration of characteristics.

Accordingly, while securing characteristics of high dielectric constant (high-K) and low leakage current, long-term thermal stability is high under storage conditions and transportation conditions, and it has strong reactivity to reactive gases such as ammonia, oxygen, or ozone, and has gas phase There is an urgent need to develop new precursors for CVD and ALD processes that can easily transport the precursors into the reaction chamber.

Republic of Korea Patent Publication No. 2012-0093165 Republic of Korea Patent Publication No. 2015-0101318 Republic of Korea Patent Registration No. 10-2231296

The present invention has been made in view of the prior art as described above, and is intended to provide a metal precursor compound for forming a semiconductor thin film capable of forming a semiconductor metal-containing thin film exhibiting high dielectric constant (high-K) characteristics.

In addition, the present invention is to provide a metal precursor composition for forming a thin film.

In addition, the present invention is to provide a method of forming a metal-containing thin film using the metal precursor compound for forming the semiconductor thin film.

In addition, the present invention is to provide a metal-containing thin film using the metal precursor composition for thin film formation.

According to one embodiment, the present invention

Provided is a metal precursor compound for forming a semiconductor thin film represented by Formula 1 below.

[Formula 1]

In Formula 1,

R ₁ to R ₆ are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms;

n and m are each independently an integer of 1 to 5;

According to another embodiment, the present invention is a metal precursor compound for forming the semiconductor thin film; It provides a metal precursor composition for forming a thin film comprising; and a solvent.

According to another embodiment, the present invention

positioning a substrate within the chamber; and

It provides a method for forming a metal-containing thin film comprising: depositing a metal-containing thin film on a substrate by supplying a metal precursor compound for forming a semiconductor thin film of the present invention.

In this case, the metal precursor compound for forming the semiconductor thin film may be dissolved in a solvent and supplied in the form of a composition.

According to another embodiment, the present invention provides a metal-containing thin film using the metal precursor composition for forming the thin film.

The metal precursor compound of the present invention can maintain a liquid state at room temperature due to structural features including an asymmetric cyclopentadiene ligand and a guanidinate ligand, and satisfies sufficient volatility and excellent chemical-thermal stability. , there is an advantage in that it is possible to prepare a high-purity sample. By using the metal precursor compound of the present invention, a metal-containing thin film having a low content of impurities and excellent uniformity can be formed. Therefore, in the present invention, by including the metal-containing thin film, it is possible to implement a semiconductor device capable of securing low leakage current characteristics and high permittivity.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the contents of the above-described invention, so the present invention is limited to those described in the drawings. should not be construed as limited.
1 is a ¹ H-NMR analysis graph of synthesized compound 1-1.
Figure 2 is a graph showing the weight loss percentage according to the temperature for the synthesized compound 1-1.
3 is a ¹ H-NMR analysis graph of the synthesized compound 1-2.
Figure 4 is a graph showing the weight loss percentage according to the temperature for the synthesized compound 1-2.
5 is a ¹ H-NMR analysis graph of synthesized compounds 1-3.
Figure 6 is a graph showing the weight loss percentage according to the temperature for the synthesized compound 1-3.
7 is a graph showing a deposition rate according to temperature of a metal-containing thin film formed using a bubble deposition method.
8 is a graph showing a deposition rate of a metal-containing thin film formed using a liquid transfer deposition method according to supply time.
9 is a graph showing a deposition rate of a metal-containing thin film formed using a liquid transfer deposition method according to temperature.
10 is a graph showing the results of XRD elemental analysis of the metal-containing thin film prepared in Example 6.
11 is a graph of ToF-SiMS analysis results for the carbon element content according to the process temperature of the metal-containing thin film formed in Example 6.
12 is a graph showing evaluation results of step coverage in a structure having an aspect ratio of 40 or more according to process temperature of a metal-containing thin film formed in Example 6.

Hereinafter, the present invention will be described in more detail. Terms or words used in this specification and claims should not be construed as being limited to ordinary or dictionary meanings, and the inventor may appropriately define the concept of terms in order to explain his or her invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

Meanwhile, the term "semiconductor thin film" used herein refers to at least one thin film among a metal thin film, a metal-containing thin film, a metal oxide thin film, and a metal nitride thin film.

In addition, the term "Cp" used herein refers to a substituted or unsubstituted cycloalkenylene group having 5 to 8 carbon atoms.

Metal precursor compound for semiconductor thin film formation

According to one embodiment, the present invention provides a metal precursor compound for forming a semiconductor thin film represented by Formula 1 below.

[Formula 1]

In Formula 1,

R ₁ to R ₆ are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms;

n and m are each independently an integer of 1 to 5;

In the case of using a low-purity solid material as a conventional precursor material, there is a reproducibility issue in the process, and a dielectric constant and leakage current according to impurities cause deterioration of thin film properties.

In the present invention, a solution to the above problems was sought by providing a metal precursor compound for forming a semiconductor thin film represented by Formula 1 below. That is, the metal precursor compound of the present invention includes a yttrium element in the structural center, and two or more asymmetric cyclopentadiene (Cp, cyclopentadiene) ligands and asymmetric guanidinate (Guanidinate, -NR) as end groups substituted for yttrium. By including the ₅ R ₆ ) ligand, it is possible to maintain a liquid state at room temperature, to satisfy sufficient volatility and excellent chemical-thermal stability, and to prepare a high-purity sample. In addition, there is an advantage in that a high-quality semiconductor metal-containing thin film having low impurity content and high uniformity can be formed using the metal precursor compound of the present invention.

Meanwhile, in Formula 1, R ₁ and R ₂ are each independently a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, R ₃ and R ₄ are each independently a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and , R ₅ and R ₆ may each independently be a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms.

Specifically, in Formula 1, R ₁ and R ₂ are each independently a substituted or unsubstituted alkyl group having 2 to 5 carbon atoms, and R ₃ and R ₄ are each independently a substituted or unsubstituted alkyl group having 2 to 4 carbon atoms. And, R ₅ and R ₆ may each independently be a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms.

More specifically, the metal precursor compound for forming a semiconductor thin film represented by Formula 1 may be at least one selected from the group consisting of compounds represented by Formulas 1-1 to 1-3 below.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

In addition, the metal precursor compound for forming a semiconductor thin film may be used in a wide range of fields where it can be used in general, and may be preferably included or used in a process of manufacturing a semiconductor material in the semiconductor field. More preferably, it can be used for manufacturing a metal-containing thin film for semiconductors.

Specifically, the metal precursor compounds for forming a semiconductor thin film may be used as a precursor for forming a metal (containing) thin film included in a semiconductor. A precursor refers to a material at a stage prior to becoming a specific material in metabolism or reaction, and a thin film used for a semiconductor can be formed by physically/chemically adsorbing the metal precursor compound onto a substrate.

Metal precursor composition for thin film formation

In another embodiment, the present invention provides a metal precursor composition for forming a thin film.

The metal precursor composition for forming a thin film includes a metal precursor compound for forming a semiconductor thin film and a solvent. At this time, the metal precursor compound for forming a semiconductor thin film is a metal precursor compound for forming a semiconductor thin film according to the present invention. As described above, A description thereof is omitted. Hereinafter, the solvent, which is another component, will be described.

The solvent is a component additionally provided so that the metal precursor composition for thin film formation of the present invention has a viscosity suitable for the liquid transfer method, and any solvent capable of dissolving or diluting the metal precursor compound for semiconductor thin film formation is the type. is not particularly limited, and examples thereof include at least one solvent selected from among saturated or unsaturated hydrocarbon solvents having 1 to 16 carbon atoms, cyclic ether organic solvents, linear ether solvents, glyme solvents, ester solvents, and tertiary amine solvents. Representative examples of the solvent include pentane, octane, tertiary amines such as dimethylethylamine, triethylamine, N,N,N',N'-tetramethylethylenediamine, tetrahydrofuran (THF), dibutyl ether, and dimethicone. and at least one solvent selected from toxymethane and dimethoxyethane.

The tertiary amine in the solvent increases the stability of the precursor material in the process of adsorbing the precursor material to the substrate, thereby minimizing the process of forming a semiconductor thin film, for example, chemical vapor deposition (CVD) in an ALD process.

The amount of the solvent is not particularly limited as long as it dissolves or dilutes the metal precursor compound for forming a semiconductor thin film to impart a viscosity suitable for the liquid transfer method, and specifically, the total weight of the metal precursor composition for forming a thin film. 0.1 to 99% by weight based on. Specifically, it may be included in 1% by weight to 50% by weight, more specifically 3% by weight to 50% by weight.

When the solvent content is within the above range, it is possible to improve the uniformity of the thin film and the effect of improving step coverage. At this time, if the solvent exceeds 99% by weight, the concentration of the precursor composition is too low and the deposition rate of the thin film slows down, resulting in poor productivity. insignificant

Method of forming a metal-containing thin film

According to another embodiment, the present invention provides a method of forming a metal-containing thin film comprising depositing a metal-containing thin film on a substrate using the metal precursor compound for forming a semiconductor thin film.

Specifically, the method includes positioning a substrate within a chamber; and

It provides a method for forming a metal-containing thin film comprising: depositing a metal-containing thin film on a substrate by supplying the metal precursor compound and/or precursor composition for forming a thin film of the present invention into the chamber.

The method of forming a metal-containing thin film of the present invention may be performed according to a conventional method of manufacturing a semiconductor thin film by vapor deposition, except for using the metal precursor compound for forming a semiconductor thin film of the present invention.

(1) positioning the substrate in the chamber

First, the method of the present invention includes the step of supplying the metal precursor compound for forming a semiconductor thin film of the present invention onto a substrate for forming a semiconductor thin film.

At this time, as the substrate for forming the semiconductor thin film, any substrate used for manufacturing a semiconductor, which needs to be coated with a semiconductor thin film due to a technical operation, can be used without particular limitation. Specifically, the substrate is a silicon substrate (Si), a silica substrate (SiO ₂ ), a silicon nitride substrate (SiN), a silicon oxy nitride substrate (SiON), a titanium nitride substrate (TiN), a tantalum nitride substrate (TaN) , a tungsten substrate (W) or a noble metal substrate such as a platinum substrate (Pt), a palladium substrate (Pd), a rhodium substrate (Rh), or a gold substrate (Au) may be used.

(2) Depositing a metal-containing thin film

In addition, in the method of the present invention, a semiconductor metal-containing thin film may be deposited on a substrate by supplying the metal precursor compound for forming a semiconductor thin film of the present invention into a chamber.

At this time, the metal precursor compound for forming a semiconductor thin film of the present invention may be supplied alone or may be supplied in the form of a metal precursor composition for forming a thin film in which it is dissolved in a solvent.

Specifically, the metal precursor compound for thin film formation of the present invention (i) raises the temperature of the precursor compound to be deposited to the vaporization temperature, injects an inert gas to generate bubbles, and vaporizes the vapor of the precursor compound in a gaseous state. ) into the reaction chamber through a carrier gas, or (ii) dissolving a metal precursor compound for forming a semiconductor thin film in an organic solvent to prepare a liquid metal precursor composition for forming a thin film, and then changing it into a gas phase through a vaporizer After that, it can be supplied through a liquid delivery system (LDS) that is transferred onto a substrate for forming a semiconductor thin film.

Since the liquid transport system vaporizes the precursor material diluted in a solvent and transports it into the deposition chamber in a more uniform state, it can be evenly adsorbed to the substrate, and as a result, the uniformity and step coating of the deposited thin film can be improved. (step coverage) characteristics can be further improved.

On the other hand, the method of the present invention further comprises the step of additionally supplying other metal precursors, if necessary, when supplying the metal precursor composition for thin film formation in order to further improve electrical properties, that is, capacitance, in the final formed semiconductor thin film. can do.

The other metal precursors include silicon (Si), titanium (Ti), germanium (Ge), strontium (Sr), niobium (Nb), barium (Ba), hafnium (Hf), zirconium (Zr), tantalum (Ta) and One or more metals (M") selected from Group 2, 3, 4 or lanthanide atoms on the periodic table may be optionally further supplied, and specifically, an alkylamide-based compound or an alkoxy-based compound containing the metal may be mentioned.

For example, when the metal is Si, other metal precursors include SiH(N(CH ₃ ) ₂ ) ₃ , Si(N(C ₂ H ₅ ) ₂ ) ₄ , Si(N(C ₂ H ₅ )(CH ₃ )) ₄ , Si(N(CH ₃ ) ₂ ) ₄ , Si(OC ₄ H ₉ ) ₄ , Si(OC ₂ H ₅ ) ₄ , Si(OCH ₃ ) ₄ , Si(OC(CH ₃ ) ₃ ) _{4 ,} etc. can be used In addition, when the metal is Zr, Zr(N(CH ₃ CH ₂ )) ₄ , Zr(Cp)(N(CH ₃ ) ₂ ) ₃ and Hf, Hf(N(CH ₃ CH ₂ )) ₄ , Hf (Cp)(N(CH3) ₂ ) ₃ and the like can be used.

The supply of the other metal precursors may be carried out in the same way as the method of supplying the metal precursor composition for thin film formation, and the other metal precursors may be supplied together with the metal precursor composition for thin film formation on a substrate for thin film formation, Alternatively, the metal precursor composition for thin film formation may be supplied sequentially after supply is completed.

The other metal precursor may be supplied in an amount of 1 to 30 parts by weight based on 100 parts by weight of the total amount of the metal compound represented by Formula 1.

At this time, if the content of the other metal precursor exceeds 30 parts by weight, there is a problem affecting the crystallinity of the thin film, and if it is less than 1, the effect of improving the dielectric constant and leakage current characteristics may be insignificant.

In the method of the present invention, the metal precursor compound for forming a semiconductor thin film or the metal precursor composition for forming a thin film and other metal precursors optionally included all have sufficient vapor pressure before being supplied into the reaction chamber to contact the substrate for forming a semiconductor thin film. It is preferable to maintain a temperature of 100 ° C to 250 ° C for vaporization, and more preferably to maintain a temperature of 150 ° C to 200 ° C.

In addition, in the method of the present invention, after the step of supplying the metal precursor compound for forming a semiconductor thin film and before the step of supplying a reactive gas, the metal precursor compound for forming a semiconductor thin film and/or the metal precursor composition for forming a thin film and other metal precursors A step of purging with an inert gas may be further included in order to move the substrate onto the substrate, to ensure that the inside of the reactor has an appropriate pressure for deposition, or to discharge impurities present in the reactor chamber to the outside. At this time, argon (Ar), nitrogen (N ₂ ), or helium (He) may be used as the inert gas, and the purge step is preferably performed such that the pressure in the reactor is 1 to 5 Torr.

In addition, in the method of the present invention, the step of depositing a metal-containing thin film on the substrate is a conventional semiconductor thin film deposition method, such as atomic layer deposition, chemical vapor deposition, under an atmosphere of 250 ° C to 400 ° C Deposition), or evaporation may be performed by at least one method, and may be specifically performed using an atomic layer deposition method.

For example, the ALD method may be performed by sequentially injecting a metal precursor compound for forming a semiconductor thin film and/or a metal precursor composition for forming a thin film and a reaction gas or a plasma of the reaction gas into a chamber under an atmosphere of 250° C. to 400° C. have. In addition, the chemical vapor deposition method or the evaporation method may be performed by simultaneously injecting the precursor and the reaction gas into the chamber at the above temperature.

At this time, in the method of the present invention, the step of depositing a metal-containing thin film on a substrate is a metal precursor compound for forming a semiconductor thin film and/or a metal precursor compound for forming a thin film using an ALD method on a substrate located in a reactor (chamber) as described above. While supplying the metal precursor composition, a reactive gas or plasma of the reactive gas is supplied into the reactor, or after supplying the metal precursor compound for forming a semiconductor thin film and/or the metal precursor composition for forming a thin film, a reactive gas or plasma of the reactive gas is supplied. The step of supplying may be further included to control the composition and type of the film to be formed.

Examples of the reactive gas include oxidizing gases such as water vapor (H ₂ O), oxygen (O ₂ ), ozone (O ₃ ) or hydrogen peroxide (H ₂ O ₂ ), hydrogen (H ₂ ), ammonia (NH ₃ ), and nitrogen monoxide ( NO), nitrous oxide (N ₂ O), nitrogen dioxide (NO ₂ ), hydrazine (N ₂ H ₄ ), and silane (SiH ₄ ), and at least one or more reducing gases such as may be applied.

Alternatively, hydrogen, ammonia, nitrogen monoxide (NO), nitrous oxide (N ₂ O), nitrogen dioxide (NO ₂ ) are used as reactive gases while supplying the metal precursor compound and/or metal precursor composition for forming the semiconductor thin film, When a reducing gas such as hydrazine or silane is supplied, a chemical reaction between the metal precursor compound for forming a semiconductor thin film and/or the metal precursor composition for forming a thin film and the reducing gas causes the yttrium oxide thin film, the yttrium nitride thin film, the metal oxide thin film, or the metal. A single film such as a nitride thin film can be formed.

In addition, the plasma of the reactive gas may be any one of RF plasma, DC plasma, or remote plasma.

The reactive gas may be directly supplied into the reduced pressure chamber through a pipe under a reduced pressure condition lower than atmospheric pressure of about 0.01 torr to about 100 torr. At this time, sufficient surface reaction can be performed under the conditions of the supply flow rate of the reactive gas and the time period of 0.01 second to 100 seconds.

Meanwhile, in the method of the present invention, deposition of a dielectric thin film formed on a substrate is performed by appropriately controlling the type and supply order of the reactive gas supplied together with the metal precursor compound for forming a semiconductor thin film and/or the metal precursor composition for forming a thin film. You can control the order.

In addition, in the method of the present invention, simultaneously with or after the step of depositing the metal-containing thin film, a reactive gas is moved onto the substrate, the reactor has an appropriate pressure for deposition, or impurities or by-products present in the reactor are discharged to the outside. To do so, purging an inert gas such as argon (Ar), nitrogen (N ₂ ), or helium (He) in the reactor may be further included.

In addition, the step of depositing a metal-containing thin film in the method of the present invention includes supplying a metal precursor compound for forming a semiconductor thin film according to the present invention; depositing a metal-containing thin film on a substrate while supplying a reactive gas or a plasma of the reactive gas into a chamber; The step of purging the inert gas may be performed as one cycle, and the cycle may be repeatedly performed one or more times.

Meanwhile, in the present invention, "semiconductor thin film" means at least one thin film among a metal-containing thin film, a metal oxide thin film, and a metal nitride thin film.

(3) surface treatment of the substrate on which the semiconductor thin film is deposited

Further, in the method of the present invention, after depositing the metal-containing thin film, a step of surface treating the formed metal-containing thin film may be additionally performed for thermal energy for deposition of the metal precursor or surface adsorption modification.

At this time, the surface treatment step is performed so that the temperature of the substrate in the reactor is 100 ° C. or more and 1,000 ° C. or less, preferably 300 ° C. or more and 500 ° C. or less, in order to manufacture a semiconductor thin film having a desired physical state and composition at a sufficient growth rate. It is desirable to do

Semiconductor thin films including metal-containing thin films

In addition, the present invention provides a metal thin film or a metal-containing thin film formed by using the metal precursor compound for forming a semiconductor thin film and/or the metal precursor composition for forming a thin film.

The metal precursor compound of the present invention may be included in the metal-containing thin film as it is, or the final form may be transformed during the process. That is, when manufacturing a thin film included in a semiconductor using the metal precursor compound of the present invention as a precursor, the final form may exist in various ways.

The metal-containing thin film of the present invention is a YxOy (wherein, 1≤x≤2, 1≤y≤3) film, an Alx1Oy1 (wherein, 1≤x1≤2, 1≤y1≤3) film, ZrOx2 (wherein, 1≤ x2≤2.5) and HfOx3 (here, 1≤x3≤2.5) may be formed by sequentially stacking one or more metal oxide films.

As such, in the present invention, an asymmetric cyclopentadiene (Cp, cyclopentadiene) ligand and a guanidinate (Guanidinate, -NR ₅ R ₆ ) ligand containing a yttrium element in the structure and an end group substituted for yttrium are used. By including, by using a metal precursor compound for forming a semiconductor thin film that can maintain a liquid state at room temperature and satisfies sufficient volatility and excellent chemical-thermal stability, a high-quality product having uniform and high-K characteristics even at high temperature A metal-containing thin film can be formed.

On the other hand, a semiconductor thin film including a metal thin film or a metal-containing thin film formed by using the metal precursor compound for forming the semiconductor thin film as a precursor is used as a high dielectric material film in a semiconductor device, in particular, a capacitor dielectric film or a gate insulating film of a transistor. useful

Specifically, the present invention can provide a capacitor dielectric film including the semiconductor thin film and a semiconductor device including the same.

That is, in a capacitor configured by sequentially stacking a lower electrode, a dielectric thin film, and an upper electrode, the lower electrode and the upper electrode may include a metal material, and the shape of the lower electrode may be a flat plate, cylinder, pillar shape, etc. It may have various shapes, and at this time, a semiconductor thin film formed by the precursor composition of the present invention may be applied as the dielectric thin film.

In this case, the semiconductor thin film may be a thin film including zirconium oxide, titanium oxide, and hafnium oxide, and at least two kinds of oxide thin films selected from Group 2, 3, and 4 or zirconium oxide, titanium oxide, and hafnium oxide on the periodic table are laminated or It can also be formed by mixing.

In the present invention, crystallinity, dielectric properties, and leakage current characteristics of the dielectric thin film may be improved by depositing the dielectric thin film of the present invention on a cylindrical or pillar-shaped lower electrode.

In addition, the present invention can provide a semiconductor device including a gate insulating film including the semiconductor thin film and a transistor including the same.

The capacitor has a configuration of a lower electrode, a dielectric layer, and an upper electrode, and a YxOy (where 1≤x≤2, 1≤y≤3) thin film may be applied to form the dielectric layer.

The transistor is formed on a substrate and includes a gate insulating layer, a gate electrode, a source region, and a drain region. The gate electrode may include a metal material, and the gate insulating layer may include a metal oxide or metal nitride thin film deposited using a composition for forming a thin film. For example, the gate insulating layer may include zirconium oxide, titanium oxide, or hafnium oxide. In addition, the gate insulating film may be formed by stacking or mixing at least two types of oxide thin films selected from among zirconium oxide, titanium oxide, and hafnium oxide. More specifically, a YxOy (where 1≤x≤2, 1≤y≤3) thin film may be applied as the gate insulating layer.

On the other hand, the semiconductor device of the present invention has the same configuration as a conventional semiconductor device except that the metal-containing thin film according to the present invention is included in a material film requiring high dielectric properties, such as the capacitor dielectric film or the gate insulating film of a transistor. .

Although the present invention has been described with preferred embodiments as described above, it is not limited to the above embodiments, and various modifications are made by those skilled in the art within the scope of not departing from the spirit of the present invention. and change is possible. Such modifications and variations are to be regarded as falling within the scope of this invention and the appended claims.

Hereinafter, a method of synthesizing a metal precursor compound for forming a semiconductor thin film and a method of forming a thin film using the same of the present invention will be described in detail with examples, but the configuration of the present invention is not limited to the following examples.

Example

I. Method for synthesizing a metal precursor compound for forming a semiconductor thin film

Example 1. Bisbutylcyclopentadienyl-diisopropyl-diethylamiguanidinato)yttrium (Y(nBuCp) of Formula 1-1 ₂ (dipdeg)) synthesis.

2048.5 ml (5.12 mol) of n-BuLi hexane solution (2.5 M) was slowly added dropwise with 625.9 g (5.12 mol) of butylcyclopentadiene in 3000 mL of THF at -78°C to prepare Li-BuCp. The solution was stirred at −78° C. for 30 min then warmed to room temperature and further stirred at room temperature for 1 hour. Add 500g (2.56 mol) of yttrium chloride and 1500mL of Toluene to a new flask. The mixture was prepared by stirring at -78 °C and then slowly adding the entire amount of the freshly prepared Li-BuCp solution to the flask containing the YCl mixture. The solution was stirred at −78° C. for 30 min then warmed to room temperature and stirred at room temperature overnight.

1024.3 ml (2.56 mol) of n-BuLi hexane solution (2.5 M) was slowly added dropwise with diethylamine (187.2 g, 2.56 mol) in 1500 mL of THF at -78°C to prepare Li-DEA. The solution was stirred at −78° C. for 30 min then warmed to room temperature and further stirred at room temperature for 1 hour. Li-dipdeg was prepared by slowly adding di-isopropylcarbodiimide (323.2 g, 2.56 mol) to a flask containing Li-DEA. The solution was stirred at -78 °C for 30 min, then warmed to room temperature and further stirred at room temperature for 2 h. The entire amount of the freshly prepared Li-dipdeg solution was slowly added dropwise to the flask containing Y(BuCp) ₂ Cl and reacted. The resulting mixture was stirred overnight. The mixture was filtered and the solvent and volatiles were evaporated under vacuum. The resulting pale yellow liquid was distilled at 175° C. and 132 mTorr. The yield was 569.6 g (42.0%). The obtained liquid compound was subjected to NMR measurement (Bruker AV400MHz HD (solvent: using benzene-d6), and the results are shown in FIG. 1 .

¹ H NMR (C ₆ D ₆ , 25° C.): 0.93 (t, 6H), 0.97 (t, 6H), 1.05 (d, 12H), 1.39 (s, 4H), 1.64 (q, 4H), 2.63 ( t, 4H), 2.79 (q, 4H), 3.55 (m, 2H), 6.15 (d, 8H).

The obtained light yellow liquid was heated at 10°C/min in an atmosphere in which nitrogen flowed at 200 mL/min, and the weight loss percentage according to temperature change was evaluated by TGA (manufactured by TA instrument (SDT Q600)), and the results were It is shown in Figure 2. Referring to Figure 2, 20.1% residual mass remained during the TGA analysis measured at a rate of 10 °C/min.

Example 2. Bisethylcyclopentadienyl-diisopropyl-ethylmethylamiguanidinato)yttrium (Y(EtCp) of Formula 1-2 ₂ (dipemg)) synthesis.

2048.5 ml (5.12 mol) of n-BuLi hexane solution (2.5 M) was slowly added dropwise with 482.2 g (5.12 mol) of ethylcyclopentadiene in 3000 mL of THF at -78°C to prepare Li-EtCp. The solution was stirred at −78° C. for 30 min then warmed to room temperature and further stirred at room temperature for 1 hour. Add 500g (2.56 mol) of yttrium chloride and 1500mL of Toluene to a new flask. The mixture was prepared by stirring at -78 °C and then slowly adding the entire amount of the freshly prepared Li-EtCp solution to the flask containing the YCl mixture. The solution was stirred at −78° C. for 30 min then warmed to room temperature and stirred at room temperature overnight.

1024.3 ml (2.56 mol) of n-BuLi hexane solution (2.5 M) was slowly added dropwise with ethylmethylamine (151.35 g, 2.56 mol) in 1500 mL of THF at -78°C to prepare Li-EMA. The solution was stirred at −78° C. for 30 min then warmed to room temperature and further stirred at room temperature for 1 hour. Li-dipemg was prepared by slowly adding di-isopropylcarbodiimide (323.2 g, 2.56 mol) to a flask containing Li-EMA. The solution was stirred at -78 °C for 30 min, then warmed to room temperature and further stirred at room temperature for 2 h. The entire amount of the freshly prepared Li-dipemg solution was slowly added dropwise to the flask containing Y(EtCp) ₂ Cl and reacted. The resulting mixture was stirred overnight. The mixture was filtered and the solvent and volatiles were evaporated under vacuum. The resulting pale yellow liquid was distilled at 180°C and 40 mTorr. The yield was 733.8 g (62.4%). The obtained liquid compound was subjected to NMR measurement (Bruker AV400MHz HD (solvent: using benzene-d6), and the results are shown in FIG. 3 .

¹ H NMR (C ₆ D ₆ , 25° C.): 0.9 (t, 3H), 1.00 (d, 12H), 1.24 (t, 6H), 2.4 (s, 3H), 2.6 (q, 4H), 2.72 ( q, 2H), 3.44 (m, 2H), 6.10 (d, 8H).

The obtained light yellow liquid was heated at 10°C/min in an atmosphere in which nitrogen flowed at 200 mL/min, and the weight loss percentage according to temperature change was evaluated by TGA (manufactured by TA instrument (SDT Q600)), and the results were It is shown in Figure 4. Referring to Figure 4, 4.8% residual mass was left during the TGA analysis.

Example 3. Synthesis of bisisopropylcyclopentadienyl-diisopropyl-ethylmethylamidoganidinato)yttrium (Y(iPrCp) 2 ( _dipemg )) of Formula 1-3.

2048.5 ml (5.12 mol) of n-BuLi hexane solution (2.5 M) was slowly added dropwise with 482.2 g (5.12 mol) of isopropylcyclopentadiene in 3000 mL of THF at -78°C to prepare Li-iPrCp. The solution was stirred at −78° C. for 30 min then warmed to room temperature and further stirred at room temperature for 1 hour. Add 500g (2.56 mol) of yttrium chloride and 1500mL of Toluene to a new flask. The mixture was prepared by stirring at -78 °C and then slowly adding the entire amount of the freshly prepared Li-iPrCp solution to the flask containing the YCl mixture. The solution was stirred at −78° C. for 30 min then warmed to room temperature and stirred at room temperature overnight.

1024.3 ml (2.56 mol) of n-BuLi hexane solution (2.5 M) was slowly added dropwise with ethylmethylamine (151.35 g, 2.56 mol) in 1500 mL of THF at -78°C to prepare Li-EMA. The solution was stirred at −78° C. for 30 min then warmed to room temperature and further stirred at room temperature for 1 hour. Li-dipemg was prepared by slowly adding di-isopropylcarbodiimide (323.2 g, 2.56 mol) to a flask containing Li-EMA. The solution was stirred at -78 °C for 30 min, then warmed to room temperature and further stirred at room temperature for 2 h. The entire amount of the freshly prepared Li-dipemg solution was slowly added dropwise to the flask containing Y(iPrCp) ₂ Cl and reacted. The resulting mixture was stirred overnight. The mixture was filtered and the solvent and volatiles were evaporated under vacuum. The resulting pale yellow liquid was distilled at 180°C and 40 mTorr. The yield was 615.3 g (49.3%). The obtained liquid compound was subjected to NMR measurement (Bruker AV400MHz HD (solvent: using benzene-d6), and the results are shown in FIG. 5 .

¹ H NMR (C ₆ D ₆ , 25° C.): 1.0 (t, 3H), 1.02 (d, 12H), 1.3 (d, 12H), 2.39 (s, 3H), 2.72 (q, 2H), 2.99 ( q, 2H), 3.44 (m, 2H), 6.16 (d, 8H).

The obtained light yellow liquid was heated at 10°C/min in an atmosphere in which nitrogen flowed at 200 mL/min, and the weight loss percentage according to temperature change was evaluated by TGA (manufactured by TA instrument (SDT Q600)), and the results were It is shown in Figure 4. Referring to Figure 4, 9.1% residual mass was left during the TGA analysis.

II. Thin film formation method

Example 4. Bubble deposition method

The liquid bisethylcyclopentadienyl-diisopropyl-ethylmethylamidoguanidinato)yttrium of Chemical Formula 1-2 obtained in Example 2 was raised to the vaporization temperature alone, and then an inert gas was supplied through the DIP line. Bubbles were generated by injection, and vapor of the precursor compound in a gaseous state was supplied into the reaction chamber through a carrier gas.

As shown in Table 1 below, while maintaining the reaction chamber at 280 to 350 ° C., the precursor compound is supplied for 4 seconds, and an inert gas is supplied for 30 seconds to perform a purge process for excess precursor, and also, an oxide film An oxidizing reaction gas for forming was supplied into the reaction chamber for 10 seconds, and an inert gas was supplied for 15 seconds to perform a purge process for excess oxidizing reaction gas.

The precursor was vaporized by heating a canister at 115° C., and ozone generated by mixing oxygen and nitrogen at a ratio of 97:3 using an ozone generator was used as the oxidizing reaction gas.

In addition, argon, an inert gas, was used as a carrier gas for delivering the precursor compound to the reaction chamber and supplied at a flow rate of 80 cc/min. In the subsequent purge process, argon was supplied at a rate of 2000 cc/min to obtain the precursor compound and the precursor compound supplied to the reaction chamber. Oxidizing reaction gases were removed.

Then, the deposition rate was measured according to the reaction chamber temperature conditions, and the results are shown in FIG. 7 .

Precursor supply time [sec] 4 purge time [sec] 30 Oxidizing gas supply time [sec] 10 purge time [sec] 15 carrier gas [sccm] 80 Reaction chamber temperature [°C] 280 to 350

Referring to FIG. 7, while maintaining the reaction chamber temperature at 280 to 350 ° C, the deposition rate showed a value around 0.6 Å / cycle, especially in the 300 to 340 ° C section, showed a value of almost 0.6 Å / cycle level. Through this result, it was confirmed that it has a wide ALD window even at high temperatures.

Examples 5 to 6. Liquid transfer deposition method

The composition obtained by dissolving the liquid bisethylcyclopentadienyl-diisopropyl-ethylmethylamidoganidinato)yttrium metal precursor compound of Formula 1-2 obtained in Example 2 in a solvent (octane) was prepared on the canister DIP line was converted into a vapor state through a vaporizer at 160° C., and then injected into the reaction chamber to perform a deposition process under the conditions shown in Table 2.

As shown in Table 2 below, while maintaining the reaction chamber at 290 to 340 ° C, the precursor compound is supplied in the range of 0.2 to 1.5 seconds, and after supply, an inert gas is supplied for 40 seconds to remove excess metal precursor compounds. A purge process was performed. In addition, a purge process was performed in which an oxidizing reaction gas for forming an oxide film was supplied into the reaction chamber in a range of 2 to 5 seconds, and then an inert gas was supplied for 15 seconds to remove excess oxidizing reaction gas.

As the oxidizing reaction gas, ozone generated by mixing oxygen and nitrogen at a ratio of 97:3 using an ozone generator was used.

In addition, argon, an inert gas, was used as a carrier gas for delivering the precursor compound to the reaction chamber and supplied at a flow rate of 400 cc/min, and the precursor compound was supplied to the reaction chamber at a flow rate of 0.01 to 0.05 g/min.

Thereafter, in the purge process, argon was supplied at 2000 cc/min to remove the precursor compound and oxidizing reaction gas supplied to the reaction chamber.

Then, the deposition rate according to supply time was measured, and the results are shown in FIG. 8 . In addition, the deposition rate was measured according to the reaction chamber temperature conditions, and the results are shown in FIG. 9 .

Example 5 Example 6 Precursor supply time [sec] 0.2~1.5 0.23 purge time [sec] 30 40 Oxidizing gas supply time [sec] 2 5 purge time [sec] 15 carrier gas [sccm] 400 Vaporizer temperature [℃] 160 Reaction chamber temperature [°C] 310 290 to 340

Referring to FIGS. 8 to 9, as the supply time of the material increases, the initial rapid deposition rate is shown, but the deposition width gradually decreases. In addition, as a result of checking the change in the deposition rate according to the temperature change at a specific supply time standard, it was confirmed that it had a constant deposition rate of 0.3Å/cycle in the range of 290 ~ 340 ℃. Therefore, through the ALD process using this material, it is possible to form a thin film with a desired deposition rate in a wide temperature range.

Experimental example

Experimental Example 1. Evaluation of thin film properties (1)

Elemental analysis and crystallinity were evaluated using the XRD method for the metal-containing thin film formed in Example 6, and the results are shown in FIG. 10 and Table 3 below.

At this time, the XRD was measured using (Rigaku smartlab, Cu Ka1 λ=1.540593Å).

Referring to FIG. 10, the composition of Y and O was confirmed at a ratio of 2:3, which is close to the stoichiometric ratio, and C and N impurities except for the Si component were not detected, confirming that it was a pure Y ₂ O ₃ thin film. . In addition, referring to Table 3 below, it can be seen that the deposited Y ₂ O ₃ thin film has cubic crystallinity.

analysis item result XRD (crystalline) Cubic crystallinity

Experimental Example 2. Evaluation of thin film properties (2)

In order to confirm the carbon content according to the process temperature for the metal-containing thin film formed in Example 6, ToF-SiMS (Cameca SC ultra, Cs 500eV) analysis was performed, and the results are shown in FIG. 11 and Table 4 below. .

analysis item above 300℃ ToF-SIMS (C content) 1x10 ^-3 or less

Referring to FIG. 11 and Table 4, it can be seen that the C content is also very low at a process temperature of 300° C. or higher, at a level of 1x10 ^-3 or less.

Experimental Example 3. Evaluation of thin film properties (3)

In order to confirm the step coverage characteristics of the metal-containing thin film formed in Example 6, the metal-containing thin film was deposited on a substrate on which a hole pattern having an aspect ratio of 40 or more was formed, and then FIB-TEM (Hitachi HD-2700, acceleration voltage 200 kV) The application uniformity according to the process temperature was evaluated by the analysis method, and the step coverage was calculated, and the results are shown in Table 5 and FIG. 12 below.

290℃ 300℃ 310℃ 320℃ Int./THK ^*) 7.9 8.2 9.2 11.9 Step Coverage - 98.5% 96.1% 98.5%

In the above table, Int/THK ^*) means the largest "Peak intensity"/"film thickness (Int./THK), and the size of the XRD crystal peak is proportional to the thickness.

Looking at Table 5 and FIG. 12, it can be seen that the step coverage shows very high uniformity at the level of 96 to 98% when a process temperature of 300 ° C or 320 ° C is applied.

Claims (15)

A metal precursor compound for forming a semiconductor thin film represented by Formula 1 below:
[Formula 1]

In Formula 1,
R ₁ to R ₆ are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms;
n and m are each independently an integer of 1 to 5;
The method of claim 1,
In Formula 1, R ₁ and R ₂ are each independently a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, R ₃ and R ₄ are each independently a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and R ₅ and R ₆ are each independently a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, a metal precursor compound for forming a semiconductor thin film.
The method of claim 1,
In Formula 1, R ₁ and R ₂ are each independently a substituted or unsubstituted alkyl group having 2 to 5 carbon atoms, R ₃ and R ₄ are each independently a substituted or unsubstituted alkyl group having 2 to 4 carbon atoms, and R ₅ and R ₆ are each independently a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms, a metal precursor compound for forming a semiconductor thin film.
The method of claim 1,
The metal precursor compound for forming a semiconductor thin film represented by Formula 1 is at least one selected from the group consisting of compounds represented by the following Formulas 1-1 to 1-3:
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

A metal precursor compound for forming a semiconductor thin film of claim 1; and
A metal precursor composition for forming a thin film comprising a solvent;
The method of claim 5,
The solvent is at least one of a saturated or unsaturated hydrocarbon solvent having 1 to 16 carbon atoms, a cyclic ether solvent, a linear ether solvent, a glyme solvent, an ester solvent, and an amine solvent.
The method of claim 5,
The solvent is pentane, octane, tertiary amine, dimethylethylamine, triethylamine, N,N,N',N'-tetramethylethylenediamine, tetrahydrofuran (THF), dibutylether, dimethoxymethane And a metal precursor composition for forming a thin film comprising at least one of dimethoxyethane.
positioning a substrate within the chamber; and
A method of forming a metal-containing thin film comprising: depositing a metal-containing thin film on a substrate by supplying the metal precursor compound of claim 1 into the chamber.
The method of claim 8,
The metal precursor compound for forming the thin film is a method of forming a metal-containing thin film that is supplied by dissolving in a solvent.
The method of claim 8,
Wherein the metal-containing thin film deposition step is performed by a bubble deposition method or a liquid transfer deposition method.
The method of claim 8,
The metal-containing thin film deposition step is a method of forming a metal-containing thin film that is performed under a temperature condition of 250 ° C. or more and 400 ° C. or less.
A metal-containing thin film formed from the metal precursor compound for forming a thin film of claim 1.
The method of claim 12,
The metal-containing thin film includes a Y _x O _y (where 1≤x≤2, 1≤y≤3) film, an Al _x1 O _y1 (where 1≤x1≤2, 1≤y1≤3) film, and ZrO _x2 (In this case, 1≤x2≤2.5) and HfO _x3 (wherein, 1≤x3≤2.5) one or more metal oxide films are sequentially stacked.
12. A capacitor dielectric film comprising a metal-containing thin film.
12. A gate insulating layer comprising a metal-containing thin film.

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