KR100622309B1 - Compound for depositing semiconductor film and method of depositing film using the same - Google Patents

Abstract

The present invention relates to a compound for semiconductor thin film deposition and a thin film deposition method using the same, the organic metal precursor represented by the following <Formula 1> or <Formula 2> and a thin film having a target thickness through a plurality of deposition and purge using the same Can be deposited.

<Formula 1>

<Formula 2>

Wherein M is Ti, Zr, Hf, Al, Ga, In, Ge, Si, Sn, Pb, P, As, Sb, Bi, S, Se, Te, V, Nb, Ta, Ce, Nd, D ₁ , R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each selected from C1-C3 alkyl (Alkyl) or hydrogen, and n is the valence of the metal. to be.

Chemical vapor deposition, atomic layer deposition, atomic layer, organometallic precursor, purge, step coverage

Description

Compound for depositing semiconductor thin film and method for thin film deposition using same {compound for depositing semiconductor film and method of depositing film using the same}

1 is a cross-sectional view of a deposition apparatus for explaining a thin film deposition method using a compound according to the present invention.

2 and 3 is a flow chart for explaining a thin film deposition method according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10 chamber 20 susceptor

30 wafer 40 container

45 gas inlet 50 pump

The present invention relates to a compound for semiconductor thin film deposition and a thin film deposition method using the same, and more particularly to a metal precursor containing a vinyl group or an acetylene group and an atomic layer deposition method and a chemical vapor deposition method for producing a metal oxide film using the same.

In recent decades, the development of the electronics industry has played a major role in the development of human life. The development direction of the electronic industry is changing due to the miniaturization, high integration, and processing speed of electronic components, and development of new electronic materials and thin film fabrication technology are essential for high integration of circuits. As the degree of integration of memory or non-memory semiconductor devices increases day by day, and the structure thereof becomes more complicated, the importance of step coverage in depositing various thin films on a substrate is increasing. However, conventionally used precursors have a problem in that they cannot be sufficiently satisfied with these requirements as precursors prepared for chemical vapor deposition. That is, since there are few precursors suitable for the atomic layer deposition method, there are many difficulties in high integration of semiconductors.

This is because it is very difficult to meet the conditions of the precursor required in the atomic layer deposition method. The conditions to be provided as metal precursors in such chemical vapor deposition or atomic layer deposition include high vaporization characteristics, large gaps in vaporization temperature and decomposition temperature, low toxicity, chemical stability, thermal stability, and ease of compound synthesis and pyrolysis. have. In addition, there should be no side reactions that spontaneously decompose or react with other substances in the process of vaporization and in the gas phase.

In addition, metal precursors for atomic layer deposition require more thermal stability and adequate reactivity with oxidants, such as H ₂ O, O ₂ , O ₃ , compared to precursors for chemical vapor deposition. Thermal stability and reactivity with oxidants are important factors in determining step coverage in atomic layer deposition.

Due to the above reasons, it is difficult to develop precursors for atomic layer deposition. Particularly, precursors for atomic layer deposition developed for manufacturing a metal thin film for semiconductor capacitors are precursors developed for chemical vapor deposition. In the case of titanium, there are typically metal chloride compounds such as titanium tetratrolide (TiCl ₄ ), metal alkoxides such as titanium tetra isopropoxide (TTIP), or metal amide compounds such as tetrakis dimethylmaminoitanium. The metal chloride compound has a high thermal decomposition temperature of the metal-Cl bond, thereby increasing the process temperature, and the leakage current characteristic tends to be deteriorated due to the residual of chlorine (Cl). In addition, the metal alkoxide has a problem that the pyrolysis temperature is somewhat low but the reactivity with oxidants, for example, H ₂ O, O ₂ , O ₃ is poor, so that the growth of the thin film is slow. In addition, the metal amide compound exhibits good reactivity with the oxidants, but is poorly deteriorated due to its poor thermal stability, and has a problem in that particles are generated in the process due to excessive instability with respect to moisture.

The present invention is to solve the above problems, to provide a metal oxide precursor precursor compound for semiconductors that prevents the generation of particles during the process, the thermal stability at the process temperature is good and has high reactivity with oxidants.

Another object of the present invention is to provide a thin film deposition method for depositing a metal oxide using the precursor compound.

Provided is a compound for semiconductor thin film deposition represented by the following <Formula 1> according to the present invention.

<Formula 1>

[Wherein,

M is selected from Ti, Zr, Hf, Al, Ga, In, Ge, Si, Sn, Pb, P, As, Sb, Bi, S, Se, Te, V, Nb, Ta, Ce, Nd, Dy And;

R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each selected from C 1 -C 3 alkyl or hydrogen;

N is the valence of the metal.]

Here, each of R ₁ and R ₂ uses methyl or ethyl, and each of R ₃ , R ₄ and R ₅ preferably uses hydrogen. The metal M is preferably selected from Zr, Hf, Ti, and Ta.

It provides a compound for semiconductor thin film deposition represented by the following <Formula 2> according to the present invention.

<Formula 2>

[Wherein,

M is selected from Ti, Zr, Hf, Al, Ga, In, Ge, Si, Sn, Pb, P, As, Sb, Bi, S, Se, Te, V, Nb, Ta, Ce, Nd, Dy And;

R ₆ , R ₇ and R ₈ are each selected from C1-C3 alkyl or hydrogen;

N is the valence of the metal.]

Herein, each of R ₆ and R ₇ uses methyl or ethyl, and R ₈ preferably uses hydrogen. The metal M is preferably selected from Zr, Hf, Ti, and Ta.

In another aspect, the present invention provides a predetermined chamber on which a wafer is mounted, and preparing a compound for depositing a semiconductor thin film according to the present invention, and injecting the compound for depositing a semiconductor thin film into the chamber in a vapor phase to form a first atom on the wafer. It provides a thin film deposition method using a semiconductor thin film deposition compound comprising the step of depositing the layer and the semiconductor thin film deposition compound and by-products remaining after the deposition.

After purging the remaining compound and the by-products for depositing the semiconductor thin film, injecting ozone into the chamber to deposit a second atomic layer and purging the ozone and by-products remaining in the chamber. It may include.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like numbers refer to like elements in the figures.

The present invention provides a precursor compound, which is defined by the following Chemical Formula 1 or Chemical Formula 2, as a precursor compound for depositing a metal oxide film for semiconductors.

Wherein M is Ti, Zr, Hf, Al, Ga, In, Ge, Si, Sn, Pb, P, As, Sb, Bi, S, Se, Te, V, Nb, Ta, Ce, Nd, Dy Is selected from.

R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each selected from C1-C3 alkyl (Alkyl) or hydrogen, and n is the valence of the metal. That is, the n ligands R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ may each be selected from methyl, ethyl, propyl or hydrogen. Can be. Preferably, R ₁ , R ₂ , R ₆ , and R ₇ are each selected from methyl or ethyl, and R ₃ , R ₄ , R ₅ , and R ₈ use hydrogen.

In more detail, in Formula 1, R ₁ and R ₂ each use methyl or ethyl, R ₃ , R ₄ and R ₅ use hydrogen, and the metal M is Ti, Zr, Hf, Any one of Ta can be selected and used.

Alternatively, in Formula 2, R ₆ and R ₇ may each use methyl or ethyl, R ₈ may use hydrogen, and the metal M may be any one selected from Ti, Zr, Hf, and Ta.

As the precursor compound of the present invention, it is preferable to use any one of methyl buteneoxy hafnium, methyl buteneoxy zirconium, methyl buteneoxy titanium, methyl buteneoxy tantalum and methyl butylene oxytitanium.

Hereinafter, the method for preparing the precursor compound of the present invention described above will be described in more detail with reference to the following examples. The following examples are carried out in an inert argon or nitrogen atmosphere using a glove box or Schlenk Line.

Example 1

Synthesis of Methyl Butene Oxyhafnium.

Referring to Scheme 1, a nucleic acid solution (100 ml) of 43.07 g (0.5 mol) of 2-methyl-3-butene-2-ol was added to 100 ml of nucleic acid to which 46.72 g (0.1 mol) of tetrakisdiethylaminohafnium was added. ) Is added under a stream of nitrogen gas and refluxed for 2 hours. After 2 hours, the reaction product is cooled down to room temperature, and at room temperature (20 ° C), a vacuum is used to remove all volatilable substances to obtain a yellow liquid.

The dried yellow liquid was distilled while maintaining a vacuum (30 mtorr) state at 110 ° C. for primary purification. The light yellow liquid obtained by primary purification was distilled again while maintaining a vacuum (30 mtorr) state at 110 ° C. 2 Tea purification was carried out to obtain 45.2 g (89%) of a high purity methylbuteneoxyhafnium compound.

Example 2

Synthesis of Methylbuteneoxyzirconium.

Referring to Scheme 2 below, a nucleic acid solution (100 ml) in which 43.07 g (0.5 mol) of 2-methyl-3-butene-2-ol was added to a 100 ml solution of 37.9 g (0.1 mol) of tetrakisdiethylaminozirconium was added. ) Is added under a stream of nitrogen gas and refluxed for 2 hours. After 2 hours, the reaction product is cooled down to room temperature, and at room temperature (20 ° C), a vacuum is used to remove all volatilable substances to obtain a yellow liquid.

The dried yellow liquid was distilled while maintaining a vacuum (30 mtorr) state at 110 ° C. for primary purification, and the light yellow liquid obtained by primary purification was distilled again while maintaining a vacuum (30 mtorr) state at 110 ° C. 2 Tea purification was carried out to obtain 37 g (87%) of a high purity methylbuteneoxyzirconium compound.

Example 3

Synthesis of Methylbuteneoxytitanium.

Referring to Scheme 3 below, a nucleic acid solution (100 ml) in which 43.07 g (0.5 mol) of 2-methyl-3-butene-2-ol was added to a 100 ml solution of 33.6 g (0.1 mol) of tetrakisdiethylaminotitanium was added. ) Is added under a stream of nitrogen gas and refluxed for 2 hours. After 2 hours, the reaction product is cooled down to room temperature, and is removed at room temperature (20 ℃) using vacuum to remove all volatilable substances to obtain a yellow liquid.

The dried yellow liquid was distilled while maintaining a vacuum (30 mtorr) state at 110 ° C. for primary purification, and the light yellow liquid obtained by primary purification was distilled again while maintaining a vacuum (30 mtorr) state at 110 ° C. 2 Tea purification was carried out to obtain 36.3 g (91%) of a high purity methylbuteneoxytitanium compound.

Example 4

Synthesis of Methyl Butene Oxy Tantalum.

Referring to Scheme 4, a benzene solution (100 ml) added with 51.6 g (0.6 mol) of 2-methyl-3-butene-2-ol was added to 100 ml of benzene with 35.8 g (0.1 mol) of tantalum chloride. It is added under a stream of gas and 50.5 g (0.5 mol) of triethylamine is added slowly and refluxed for 2 hours. After 2 hours, the reaction product was cooled down to room temperature, and then (C ₂ H ₅ ) ₃ NHCl was removed by filtration, and at room temperature (20 ° C), all volatile substances were removed using a vacuum to obtain a yellow liquid. .

The dried yellow liquid was distilled while maintaining a vacuum (30 mtorr) state at 110 ° C. for primary purification, and the light yellow liquid obtained by primary purification was distilled again while maintaining a vacuum (30 mtorr) state at 110 ° C. The second purification was carried out to obtain 51.5 g (85%) of a high purity methylbuteneoxy tantalum compound.

Example 5

Synthesis of Methylbutyneoxytitanium.

Referring to Scheme 5 below, a nucleic acid solution (100 ml) in which 43.07 g (0.5 mol) of 2-methyl-3-butyn-2-ol was added to a 100 ml solution of 33.6 g (0.1 mol) of tetrakisdiethylaminotitanium was added. ) Is added under a stream of nitrogen gas and refluxed for 2 hours. After 2 hours, the reaction product is cooled down to room temperature, and at room temperature (20 ° C), a vacuum is used to remove all volatilable substances to obtain a yellow liquid.

The dried yellow liquid was distilled while maintaining a vacuum (30 mtorr) state at 110 ° C. for primary purification, and the light yellow liquid obtained by primary purification was distilled again while maintaining a vacuum (30 mtorr) state at 110 ° C. 2 Tea purification was carried out to obtain 32.7 g (87%) of a high purity methylbutyneoxytitanium compound.

Table 1 is a table listing the analysis results according to the nuclear magnetic resonance analysis measured to identify the properties of the compounds and the compounds according to the above embodiment.

As shown in Table 1, the color and hydrogen nuclear magnetic resonance ( ¹ H-NMR) analysis data of the compounds according to the first to fifth embodiments of the present invention are shown.

In general, the alkoxy metal compound is very weak in reactivity with ozone, which makes it difficult to deposit an atomic layer using ozone. However, the alkenoxy metal compound and the alkynoxy metal compound developed in the present invention have very high reactivity with ozone. Atomic layer deposition is very easy. In addition, in the case of alkylamino metal compounds, which are widely used in the past, they are excessively sensitive to moisture and air, thereby causing problems of deterioration and particle generation of precursor compounds in the process. In the case of excellent thermal stability and excellent stability against moisture can improve the problems of deterioration or particle generation of the precursor compound.

In another aspect, the present invention can be prepared by the metal oxide film or metal nitride thin film by chemical vapor deposition or atomic layer deposition using the precursor compound defined in the formula (1) or (2).

Hereinafter, a method of depositing a metal oxide film of the present invention will be described with reference to the accompanying drawings.

1 and 2, first, the wafer 30 is mounted on the susceptor 20 inside the reaction chamber 10, and the temperature of the chamber 10 is maintained at about 200 ° C. to 500 ° C. (S10). .

Next, the raw material precursor of the present invention contained in the predetermined container 40 is supplied to the gas injection hole 45 (S20). At this time, the raw material precursor is supplied in a vaporized state, and is supplied to the gas injection hole 45 together with a predetermined carrier gas. Of course, each may be supplied through a separate gas inlet (not shown). To this end, one side of the gas inlet may be supplied by vaporizing the raw material precursor, and the other side of the gas inlet may supply the transport gas to prevent particle generation. In addition, the raw material precursor may be heated to a temperature of room temperature to 100 ° C, and then injected into the chamber 10 together with the transport gas. In addition, although the inert gas is used as the transport gas, at least one of hydrogen (H), nitrogen (N ₂ ), argon (Ar), and helium (He) may be used.

As a result, an atomic layer having a thin thickness is deposited on the wafer 30 mounted in the chamber 10 by the raw material precursor and the transport gas supplied into the reaction chamber 10 (S30). After purging using an inert gas to discharge the raw material remaining in the chamber 10 (S40). Alternatively, vacuum purging may be performed. As a result, unreacted raw materials or by-products are discharged to the outside through the pump 50.

The above-described deposition and purging are repeatedly performed a plurality of times until the thin film formed using the precursor of the present invention has a target thickness (S50). At this time, by introducing a reaction gas such as water (H ₂ O), ozone (O ₃ ) or ammonia (NH ₃ ) together into the chamber, a thin film having a desired composition such as oxide and nitride can be prepared, and the deposition rate and the deposition The temperature can be improved.

Although the atomic layer deposition method has been described above, a semiconductor thin film having desired characteristics may be manufactured by chemical vapor deposition using the precursor compound of the present invention as a raw material. Generally, the purge step is omitted in chemical vapor deposition.

Hereinafter, a method of preparing the HfO ₂ thin film using the precursor compound methylbuteneoxyhafnium prepared through the first embodiment of the present invention will be described in more detail.

1 and 3, the temperature of the silicon wafer 30 substrate in the chamber 10 is about 350 ° C., and the temperature of the methylbuteneoxy hafnium precursor in the stainless steel bubbler container 40 is 60 ° C. Referring to FIGS. do. Subsequently, first, methyl buteneoxy hafnium precursor is injected into the reaction chamber for about 5 seconds using argon gas as a transport gas (S100). This results in the formation of an atomic layer as previously mentioned. Second, purging with the vacuum pump 50 for about 5 seconds (S110) to remove the residual gas or methyl butene oxy hafnium precursor present in the chamber (10). Third, ozone (O ₃ ) is injected for about 5 seconds (S120) to react with the precursor adsorbed on the silicon wafer 30 to form an HfO ₂ thin film. Fourth, the residue decomposed by the reaction for about 5 seconds to purge again by using the vacuum pump 50 (S130) to remove. Through the above-described process step, an HfO ₂ thin film having a thickness of about 0.6 mW per cycle is formed. Thus formed HfO ₂ thin film can be repeated by the above cycle according to the desired characteristics to adjust the film thickness. Such a thin film may be used in an insulating film, a dielectric film, a diffusion barrier, a barrier film, a metal film, or the like of a semiconductor device to prevent metal diffusion, and may be used in an area requiring excellent step coverage.

In addition, it will be described in more detail through the method for producing a ZrO ₂ thin film using the compound precursor methylbuteneoxyzirconium prepared in the second embodiment of the present invention.

1 and 3, the temperature of the silicon wafer 30 substrate in the chamber 10 is about 350 ° C., and the temperature of the methylbuteneoxyzirconium precursor in the stainless steel bubbler container 40 is 60 ° C. Referring to FIGS. do. Subsequently, first, methyl buteneoxy zirconium precursor is injected into the reaction chamber for about 5 seconds using argon gas as a transport gas (S100). This results in the formation of an atomic layer as previously mentioned. Second, purging with the vacuum pump 50 for about 5 seconds (S110) to remove the residual gas or methyl butene oxy zirconium precursor present in the chamber (10). Third, ozone (O ₃ ) is injected for about 5 seconds (S120) to react with the precursor adsorbed on the silicon wafer 30 to form a ZrO ₂ thin film. Fourth, the residue decomposed by the reaction for about 5 seconds to purge again by using the vacuum pump 50 (S130) to remove. Through the above-described process step, a ZrO ₂ thin film having a thickness of about 0.6 mW per cycle is formed. The ZrO ₂ thin film formed as described above may adjust the film thickness by repeating the above cycle according to desired characteristics. Such a thin film may be used in an insulating film, a dielectric film, a diffusion barrier, a barrier film, a metal film, or the like of a semiconductor device to prevent metal diffusion, and may be used in an area requiring excellent step coverage.

As described above, the present invention provides a metal oxide film precursor compound having excellent properties. That is, it provides a compound having good volatility and thermal stability at high process temperature, high reactivity with oxidants, and low metal toxicity, low toxicity, chemical stability, easy synthesis and pyrolysis of the compound. Can be.

In addition, a thin film having excellent step coverage may be formed by chemical vapor deposition or atomic layer deposition using a metal oxide film precursor compound.

Claims (8)

It is represented by <Formula 1>, <Formula 1>

M is selected from Ti, Zr, Hf, Al, Ga, In, Ge, Si, Sn, Pb, P, As, Sb, Bi, S, Se, Te, V, Nb, Ta, Ce, Nd, Dy Become; R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each selected from C 1 -C 3 alkyl or hydrogen; N is a valence of a metal compound for semiconductor thin film deposition. The method according to claim 1, Wherein each of R ₁ and R ₂ uses methyl or ethyl, and each of R ₃ , R ₄ and R ₅ uses hydrogen. It is represented by <Formula 2>, <Formula 2>

M is selected from Ti, Zr, Hf, Al, Ga, In, Ge, Si, Sn, Pb, P, As, Sb, Bi, S, Se, Te, V, Nb, Ta, Ce, Nd, Dy Become; R ₆ , R ₇ and R ₈ are each selected from C1-C3 alkyl or hydrogen; N is a valence of a metal compound for semiconductor thin film deposition. The method according to claim 3, Each of R ₆ and R ₇ uses methyl or ethyl, and R ₈ uses hydrogen. The method according to any one of claims 1 to 4, The metal M is a compound for semiconductor thin film deposition, characterized in that selected from Zr, Hf, Ti, Ta used. Providing a predetermined chamber on which a wafer is mounted and a compound for depositing a semiconductor thin film according to any one of claims 1 to 4; Depositing a first atomic layer on the wafer by injecting the semiconductor thin film deposition compound into the chamber in a vapor phase; And After the deposition, the thin film deposition method using a semiconductor thin film deposition compound comprising the step of purging the remaining compound and semiconductor by-product deposition. The method according to claim 6, After purging the remaining compound and the by-products for depositing the semiconductor thin film, Injecting ozone into the chamber to deposit a second atomic layer; And Thin film deposition method using the compound for semiconductor thin film deposition further comprising the step of purging the ozone and by-products remaining in the chamber. The method according to claim 6, The metal M is a thin film deposition method using a compound for semiconductor thin film deposition, characterized in that selected from Zr, Hf, Ti, Ta.

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