KR101380317B1 - Cyclic aminosilane compounds having excellent affinity towards silicon and metal atoms, preparing method thereof, and its application - Google Patents

Abstract

상기 화학식에서, n 및 m은 각각 독립적으로 0 내지 5의 정수이고, X는 각각 독립적으로 산소 원자, 황 원자 또는 NR기이고, R₁ 및 R₂는 각각 독립적으로 수소 원자, C1-C10 알킬기, C1-C10 알콕시기, C6-C12 아릴기, 비닐기 또는 알릴기이며, 및 R은 수소원자 또는 C1-C10 알킬기이다. 본 발명에 따른 상기 고리형 아미노실란 화합물은 실리콘 원자 및 금속 원자에 강한 친화력을 나타내기 때문에 이를 이용하면 고품질의 실리콘막을 효율적으로 얻을 수 있다.Disclosed are a cyclic aminosilane compound including a oxygen atom or a sulfur atom and a nitrogen atom together in one ring represented by one of the formulas (1) to (4), a method for preparing the same, and an application thereof:

In the above formula, n and m are each independently an integer of 0 to 5, X is each independently an oxygen atom, a sulfur atom or an NR group, R ₁ and R ₂ are each independently a hydrogen atom, a C1-C10 alkyl group, A C1-C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group, and R is a hydrogen atom or a C1-C10 alkyl group. Since the cyclic aminosilane compound according to the present invention exhibits a strong affinity for silicon atoms and metal atoms, it is possible to efficiently obtain a high quality silicon film.

Description

Cyclic aminosilane compounds having excellent affinity towards silicon and metal atoms, preparing method approximately, and its application}

The present invention relates to a cyclic aminosilane compound containing an oxygen atom or a sulfur atom and a nitrogen atom, a method for preparing the same, and an application thereof. More specifically, the present invention relates to a cyclic aminosilane compound capable of exhibiting strong affinity for silicon atoms and metal atoms as a silicon precursor compound used in the manufacture of semiconductor devices, a method for producing the same, and applications thereof.

Various silicon precursors for forming a silicon film or a material film containing silicon have been developed in the manufacturing process of a semiconductor device. Among them, bisdiethylaminosilane (BDEAS) and di-iso-propylaminosilane (DIPAS) have been evaluated as the most excellent silicon precursors and have recently been adopted for the development of semiconductor devices with a line width of 20 nm or less. The chained aminosilanes BDEAS and DIPAS belong to low boiling compounds. However, since BDEAS has a chemical structure in a chain structure, it has a low affinity and bonding strength to substructures (hereinafter, simply referred to as 'substructures') such as silicon oxide films, silicon nitride films, or various metal wiring films, so that deposition of low silicon films is performed. Speed, high pore density in the deposited silicon film, and low deposition uniformity of the deposited silicon film. Recently, as the line width becomes smaller, DIPAS having a relatively small molecular size is widely used. However, this compound is also a chained alkyl amine, resulting in poor affinity and binding capacity for the underlying structure.

Therefore, there is a demand for the development of a silicon precursor that can solve the problems of the conventional chain silicon precursor described above.

It is an object of the present invention to provide advantages such as high deposition rate of silicon film, low pore density in deposited silicon film, and / or high deposition uniformity of deposited silicon film due to high affinity and bonding strength with underlying structures in the manufacturing process of semiconductor devices. It is to provide a silicon precursor that can represent.

Another object of the present invention is to provide a method for producing the silicon precursor described above.

Still another object of the present invention is to provide a thin film forming method using the silicon precursor described above.

According to an aspect of the present invention,

Provided are a cyclic aminosilane compound comprising an oxygen atom or a sulfur atom and a nitrogen atom together in one ring or comprising two nitrogen atoms.

In one embodiment of the present invention, the cyclic aminosilane compound may be represented by any one of the following formulas (1) to (4):

In the above formula, n and m are each independently an integer of 0 to 5, each X is independently an oxygen atom, a sulfur atom or an NR group, R1 and R2 are each independently a hydrogen atom, a C1-C10 alkyl group, C1- A C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group, and R is a hydrogen atom or a C1-C10 alkyl group.

In one embodiment of the present invention, the cyclic aminosilane compound is any of a morpholinosilane compound, a thiomorpholinosilane compound represented by the following formulas (5) to (8), N-methyl piperazinosilane Can be one :.

.

.

According to another aspect of the present invention,

According to Scheme 1 below, one ring is formed by reaction of a halogenated silane compound (A) with a cyclic amine compound (B) containing oxygen atoms or sulfur atoms and nitrogen atoms together in one ring or two nitrogen atoms. A cyclic comprising the step of obtaining a cyclic aminosilane compound (1), (2), (3), or (4) which together contains an oxygen atom or a sulfur atom and a nitrogen atom or comprising two nitrogen atoms Provided are methods for preparing aminosilane compounds:

[Reaction Scheme 1]

Wherein A, B, C, and D are each independently F, Cl, Br, I or a hydrogen atom, n and m are each independently integers of 0 to 5, X is each independently an oxygen atom, sulfur An atom or an NR group, R1 and R2 are each independently a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group, and R is a hydrogen atom or a C1-C10 alkyl group to be.

In one embodiment of the present invention, the chemical reaction according to Scheme 1 occurs in an organic solvent, the organic solvent is C4 to C10 alkanes, C4 to C10 cycloalkanes, C6 to C8 aromatic hydrocarbons, C2 to C10 aliphatic ethers, C4 To C10 cyclic aliphatic ethers or mixtures thereof.

In one embodiment of the present invention, the halogenated silane compound (A) may be a chlorine substituted chlorine compound represented by the following formula (C), (D), (E) or (F):

.

.

Another aspect of the present invention to achieve the above another technical problem,

After reacting phenylsilane with trifluoromethanesulfonic acid to obtain silyl triflate, the silyl triflate contains oxygen or sulfur atom and nitrogen atom together in one ring or two nitrogen atoms. There is provided a process for the preparation of a cyclic aminosilane compound comprising the step of reacting with a cyclic amine compound (B) comprising the following cyclic aminosilane compound (1):

,

.

,

.

That is, according to the method for preparing the cyclic aminosilane compound, as shown in Scheme 2 below, phenylsilane and trifluoromethanesulfonic acid are reacted to obtain silyl triflate, and then the silyl triflate A cyclic aminosilane compound (1) is obtained by reacting with a cyclic amine compound (B) which together contains an oxygen atom or a sulfur atom and a nitrogen atom or comprising two nitrogen atoms in the ring:

[Reaction Scheme 2]

In the above formula, n and m are each independently an integer of 0 to 5, each X is independently an oxygen atom, a sulfur atom or an NR group, R1 and R2 are each independently a hydrogen atom, a C1-C10 alkyl group, C1- A C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group, and R is a hydrogen atom or a C1-C10 alkyl group.

Another aspect of the present invention to achieve the above another object,

As a thin film formation method,

Containing a silicon film or silicon on a substrate by a deposition process using a precursor comprising an oxygen atom or a sulfur atom and a nitrogen atom together in one ring, or a cyclic aminosilane compound containing two nitrogen atoms It provides a thin film forming method comprising the step of forming a material film.

A cyclic aminosilane compound including an oxygen atom or a sulfur atom and a nitrogen atom in one ring or two nitrogen atoms in one ring according to an aspect of the present invention exhibits strong affinity with silicon atoms and metal atoms. This is presumably because the cyclic aminosilane compound further has oxygen atoms, sulfur atoms, and nitrogen atoms having unshared electron pairs that can increase the interaction with silicon atoms, metal atoms and the like in one ring. The compound also has a high boiling point compared to the molecular size due to the strong intermolecular polar interactions. Therefore, the cyclic aminosilane compound according to an aspect of the present invention may be a silicon film such as an amorphous silicon film, a single crystal silicon film or a polycrystalline silicon film; For example, it is used for the deposition process of a material film containing silicon such as a polysilicon film, a silicon oxide film or a silicon nitride film, a metal silicon oxide film, or a metal silicon nitride film (hereinafter simply referred to as a 'silicon film'). The following effects can be achieved.

(1) Since the molecular size is small, many molecules per unit area of the lower structure are adsorbed in the deposition process proceeding at high temperature, so that the deposition rate of the silicon film, the deposition density of the silicon film, and the deposition uniformity, that is, the step coverage of the silicon film, are improved.

(2) Because of having a strong affinity with silicon atoms or metal atoms in the lower structure, not only the adhesion with the lower structure is large, but also the deposition rate of the silicon film, the deposition density of the silicon film, and the deposition uniformity of the silicon film, that is, the step coverage, are improved.

(3) Since the boiling point is high, the deposition process at a high temperature can be performed to further improve the deposition rate of the silicon film, the deposition density of the silicon film, and the deposition uniformity, that is, the step coverage.

1 is a graph showing the results of gas chromatography-mass spectrometry (GC-MASS) on morpholinosilanes synthesized in Example 2. FIG.
2A and 2B are graphs showing the results of ¹ H-NMR and ¹³ C-NMR structural analysis to confirm the structure of the morpholinosilanes synthesized in Example 2, respectively.
3 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for dimorpholinosilanes synthesized in Example 3. FIG.
4A and 4B are graphs showing the results of ¹ H-NMR and ¹³ C-NMR structural analysis to confirm the structure of the dimorpholinosilanes synthesized in Example 3, respectively.
5 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for trimorpholinosilanes synthesized in Example 4. FIG.
6A and 6B are graphs showing the results of ¹ H-NMR and ¹³ C-NMR structural analysis to confirm the structure of the trimorpholinosilanes synthesized in Example 4, respectively.
7 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for dithiomorpholinosilanes synthesized in Example 5. FIG.
8 is a graph showing the results of ¹ H-NMR structural analysis for confirming the structure of dithiomorpholinosilane synthesized in Example 5. FIG.
9 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for thiomorpholinosilanes synthesized in Example 6. FIG.
10 is a graph showing the results of ¹ H-NMR structural analysis for confirming the structure of thiomorpholinosilane synthesized in Example 6. FIG.

Hereinafter, a cyclic aminosilane compound, a method of manufacturing the same, and a method of manufacturing a semiconductor device using the same according to embodiments of the present invention will be described in detail.

The cyclic aminosilane compound according to the present invention is a cyclic aminosilane compound which includes an oxygen atom or a sulfur atom and a nitrogen atom together in one ring or includes two nitrogen atoms. The cyclic aminosilane compound is distinguished from the chained aminosilane compound which is commonly used as a silicon precursor, and a new chemical structure including oxygen atoms or sulfur atoms and nitrogen atoms together in one ring or two nitrogen atoms. Cyclic aminosilane compound. This cyclic aminosilane compound is a new type of silicon precursor with low molecular weight, high boiling point, and good binding power. That is, the compound has a high boiling point relative to low molecular weight due to strong intermolecular polar interactions due to oxygen atoms or sulfur atoms with lone pairs and additional nitrogen atoms with high electronegativity. In addition, oxygen atoms, sulfur atoms, and nitrogen atoms having unshared electron pairs present in one ring may increase interaction with silicon atoms, metal atoms, and the like on the surface of the underlying structure. That is, the oxygen atom or sulfur atom and nitrogen atom having the lone pair have a strong affinity with Si or Si-O, Si-OH on the surface of the lower structure in the manufacture of the semiconductor device. Therefore, the cyclic aminosilane compound of the present invention has excellent deposition property on the substructure. Therefore, when the cyclic aminosilane compound of the present invention is used in the deposition process of a silicon film during the manufacturing process of a semiconductor device, not only the deposition rate of the silicon film, the deposition density of the silicon film, and the deposition uniformity of the silicon film, that is, the step coverage, but also the lower structure and the A silicon film having a strong bonding force can be obtained. Therefore, the cyclic aminosilane compound of the present invention can be usefully used as a silicon precursor in the deposition process during the manufacturing process of the semiconductor device.

Said cyclic aminosilane compound of the present invention may be represented by any one of the following formulas (1) to (4):

In the above formula, n and m are each independently an integer of 0 to 5, each X is independently an oxygen atom, a sulfur atom or an NR group, R1 and R2 are each independently a hydrogen atom, a C1-C10 alkyl group, C1- A C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group, and R is a hydrogen atom or a C1-C10 alkyl group.

N and m are each independently an integer of 1 to 3, more preferably each independently 1 or 2. When R ₁ and R ₂ are each independently C 1 -C 10 alkyl groups, the alkyl group is preferably a C 1 -C 5 alkyl group, more preferably a C 1 -C 3 alkyl group. Specific examples of the alkyl group include methyl, ethyl, propyl, butyl, and pentyl. When R ₁ and R ₂ are each independently C 1 -C 10 alkoxy groups, the alkoxy groups are preferably C 1 -C 5 alkoxy groups, more preferably C 1 -C 3 alkoxy groups. Specific examples of the alkyl group include methoxy, ethoxy, protoxy, butoxy, and pentoxy. When R ₁ and R ₂ are each independently a C6-C12 aryl group, the aryl group may be substituted with a C1-C5 alkyl group or a C1-C5 alkoxy group. Specific examples of the aryl group include phenyl, tolyl and naphthyl. R is a C1-C10 alkyl group, preferably a C1-C5 alkyl group, more preferably a C1-C3 alkyl group. Specific examples of the alkyl group include methyl, ethyl, propyl, butyl, and pentyl.

Specific examples of the cyclic aminosilane compound include morpholinosilane compounds, thiomorpholinosilane compounds, or N-alkyl piperazinosilane compounds represented by the following formulas (5) to (8):

Next, a method for preparing the cyclic aminosilane compound according to specific embodiments of the present invention will be described in detail.

A method for producing a cyclic aminosilane compound according to one embodiment of the present invention is a direct synthesis method using a halosilane gas, as shown in Scheme 1 below, and oxygen in one ring with a halogenated silane compound (A). Containing oxygen atoms or sulfur atoms and nitrogen atoms together in one ring by condensation of a cyclic amine compound (B) containing atoms or sulfur atoms and nitrogen atoms together or comprising two nitrogen atoms Obtaining a cyclic aminosilane compound (1), (2), (3), or (4) comprising a nitrogen atom:

[Reaction Scheme 1]

Wherein A, B, C, and D are each independently F, Cl, Br, I or H, and n, m, X, R1, and R2 are as described above.

In the reaction, the usage ratio of the halogenated silane compound (A) and the cyclic amine compound (B) is 1 to 2.5 times or more of the cyclic amine compound (B) based on the theoretical reaction ratio determined according to stoichiometry. Use in excess of less than 2 times, preferably about 1.1 to 1.5 times, is preferable in terms of increasing the yield of the product.

The reaction typically proceeds for about 6 to about 12 hours, preferably about 4 to about 8 hours, at a reaction temperature of -30 ° C to 10 ° C, preferably at -20 ° C to 0 ° C.

The chemical reaction according to Scheme 1 takes place in an organic solvent. The organic solvent may be C4 to C10 alkanes, C4 to C10 cycloalkanes, C6 to C8 aromatic hydrocarbons, C2 to C10 aliphatic ethers, C4 to C10 cyclic aliphatic ethers, or mixtures thereof.

The C4 to C10 alkane solvent is preferably a C4 to C7 alkane solvent. Specific examples of the alkane solvent include butane, pentane, n-hexane, heptane and octane. The C4 to C10 cycloalkane is preferably C4 to C7 cycloalkane. Specific examples of the cycloalkane solvent include cyclobutane, cyclopentane, cyclohexane, and cycloheptane. Specific examples of the C6 to C8 aromatic hydrocarbon solvent include benzene, toluene, and xylene. The C2 to C10 aliphatic ether solvent is preferably C4 to C8 aliphatic ether. Specific examples of such aliphatic ether solvents include diethyl ether (commonly referred to as ether), dipropyl ether, dibutyl ether, methyl ethyl ether and dimethoxyethane. The C4 to C10 cyclic aliphatic ether is preferably a C4 to C7 cyclic aliphatic ether. Specific examples of the cyclic aliphatic ether include tetrahydrofuran (THF) and dioxane.

Typically, the amount of the organic solvent used in the chemical reaction according to Scheme 1 is such that the total concentration of the reaction reagent in the organic solvent is about 30 to about 90% by weight, preferably about 50 to about 80% by weight. to be.

The halogenated silane compound (A) may be a silane compound substituted with chlorine represented by the following formula (C), (D), (E) or (F):

.

.

The cyclic amine compound (B) including oxygen atoms or sulfur atoms and nitrogen atoms together in one ring capable of reacting with the halogenated silane compound (A) or two nitrogen atoms may be represented by the following formula have:

In the above formula, n, m, X, R ₁ and R ₂ are as described above.

For example, when X is an oxygen atom, the cyclic amine compound (B) may be represented by the following formula (G '):

Specific examples of the cyclic amine compound (B) include the cyclic amine compounds listed in Table 1 below.

No. Compound name Boiling point
(° C) Molecular Weight Chemical structure One 1,3-oxazetidine 73.093 59.0672

2 Oxazolidine 99.2 73.0938

3 2,6-dimethylmorpholine 147 115.17

4 3-methylmorpholine 137 101.15

5 Morpholine 132 87.12

6 1-methylpiperazine


139 100.16

7 Thiomorpholine 166.87 103.19

For example, when the halogenated silane compound (A) is chlorosilane represented by the formula (C) and the cyclic amine compound (B) is morpholine, Scheme 1 may be represented by Scheme 3 below. Thus, morpholinosilane is obtained.

[Reaction Scheme 3]

.

.

For example, when the halogenated silane compound (A) is dichlorosilane represented by the formula (D) and the cyclic amine compound (B) is morpholine, Scheme 1 may be represented by Scheme 4 below. In this way, dimorpholinosilane is obtained.

[Reaction Scheme 4]

.

.

The method for producing a cyclic aminosilane compound according to another embodiment of the present invention uses a synthesis method using trifluoromethanesulfonic acid, which is a super acid. That is, the method for producing a cyclic aminosilane compound of this type is to react with phenylsilane and trifluoromethanesulfonic acid to obtain silyl triflate as shown in Scheme 2 below, and then the silyl triflate A cyclic aminosilane compound (1) is obtained by reacting with a cyclic amine compound (B) which together contains an oxygen atom or a sulfur atom and a nitrogen atom or comprising two nitrogen atoms in the ring:

[Reaction Scheme 2]

Wherein n, m, X, R ₁ and R ₂ are as defined above. In the cyclic amine compound (B), when X is an oxygen atom, Scheme 2 becomes the following Scheme 2 '.

Scheme 2 '

Wherein n, m, R ₁ and R ₂ are each independently as defined above.

In the synthesis scheme according to Scheme 2, only the synthesis of the cyclic aminosilane compound (1) in which only one cyclic amine compound (B) is substituted is shown for convenience, but in the form in which two or more cyclic compounds are substituted It can also be applied to the synthesis of cyclic amino silane compounds (2), (3), or (4).

The morpholinosilane may be prepared for practical use by a direct synthesis method through a route as shown in Scheme 3 above, and may also be prepared for practical use by a synthetic method using a super acid through a route according to Scheme 5 below. Can be. That is, the morpholinosilanes belonging to the cyclic aminosilane compound (1) react with phenylsilane and trifluoromethanesulfonic acid to obtain silyl triflate with the release of benzene, as shown in Scheme 5 below, and then the silyl It can also be made practically by a synthesis method comprising the step of reacting triflate with morpholine to obtain morpholinosilanes:

[Reaction Scheme 5]

.

.

The cyclic aminosilane compound (2), (3), or (4) in a form in which two or more cyclic amine compounds (B) are substituted in the silicon atom of silane is a cyclic aminosilane compound according to Scheme 2 Even in the case of using the production method can be obtained in a yield and speed that can be practically used, in the case of using the direct synthesis method according to the reaction scheme 1 relatively can be obtained in high purity and high yield within a short reaction time and toxic seconds It is preferred because it does not handle strong acids. For example, as described above, the dimorpholinosilane can be obtained in a yield and speed that can be practically used when using the method for preparing the cyclic aminosilane compound according to Scheme 2, but according to Scheme 4 directly. It can be obtained with high purity and high yield within a short reaction time by the synthesis method.

The chemical reaction using the super acid trifluoromethanesulfonic acid according to Scheme 2 also occurs in an organic solvent as in the direct synthesis method according to Scheme 1. The organic solvent may be C4 to C10 alkanes, C4 to C10 cycloalkanes, C6 to C8 aromatic hydrocarbons, C2 to C10 aliphatic ethers, C4 to C10 cyclic aliphatic ethers, or mixtures thereof. Meanwhile, the reaction of the second step of the chemical reaction using the super acid trifluoromethanesulfonic acid according to Scheme 2 proceeds in the presence of a base such as triethylamine and tributylamine. Wherein the base neutralizes the super acid generated in the reaction. The amount of base used for the reaction is suitably 1 to 1.1 moles based on 1 mole of super acid.

The molar ratio of phenylsilane: trifluoromethanesulfonic acid: cyclic amine compound (B) in a chemical reaction using superfluoro acid trifluoromethanesulfonic acid according to Scheme 2 is typically 1: 1: 1 to 1: 1. 1: 0.9, preferably 1: 1: 1 to 1: 1: 0.8. The reaction typically proceeds at a reaction temperature of −30 ° C. to 10 ° C., preferably at a reaction temperature of −20 ° C. to 0 ° C. for about 1 to about 4 hours, preferably about 1 to about 2 hours.

Typically, the amount of the organic solvent used in the chemical reaction according to Scheme 2 is such that the total concentration of the reaction reagent in the organic solvent is about 30 to about 90% by weight, preferably about 50 to about 80% by weight. to be.

According to another aspect of the present invention, a method for forming a thin film includes a precursor including an oxygen atom or a sulfur atom and a nitrogen atom together in one ring or a cyclic aminosilane compound including two nitrogen atoms. Forming a silicon film or a material film containing silicon on the substrate.

A cyclic amine compound including an oxygen atom or a sulfur atom and a nitrogen atom together in one ring or two nitrogen atoms in one ring according to an aspect of the present invention may have affinity with an underlying structure including a silicon atom or a metal atom and Due to the high bonding strength, when used to form a silicon film on a silicon wafer, a silicon oxide film, a silicon nitride film, and a metal wiring layer in a semiconductor device manufacturing process, a high silicon film deposition rate, low pore density in the deposited silicon film, and / or deposition Advantages such as high deposition uniformity of the formed silicon film. Therefore, forming a polysilicon thin film using silicon as a seed using the thin film forming method according to another aspect of the present invention is effective for improving the surface roughness of polysilicon, and also gap fill of polysilicon. It can also be effective in improving the polysilicon void problem that is a problem during the process. In addition, when using the method of forming a thin film according to another aspect of the present invention, using an organometallic precursor together with the precursor is useful for forming a capacitor of a semiconductor device, for example, a capacitor of a DRAM semiconductor device.

The cyclic aminosilane compound used in the thin film forming method according to another aspect of the present invention is a compound represented by any one of the following formulas (1) to (4):

In the above formula, n and m are each independently an integer of 0 to 5, each X is independently an oxygen atom, a sulfur atom or an NR group, R1 and R2 are each independently a hydrogen atom, a C1-C10 alkyl group, C1- A C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group, and R is a hydrogen atom or a C1-C10 alkyl group.

The cyclic aminosilane compound may be any one of a morpholinosilane compound, a thiomorpholinosilane compound, or an N-alkyl piperazinosilane compound represented by the following Formulas (5) to (8):

.

.

In the method of forming a thin film according to another aspect of the present invention, the deposition process is not particularly limited, but a deposition process used in manufacturing a semiconductor device, a solar cell, or the like, for example, an atomic layer deposition process (ALD) or a chemical vapor deposition process (CVD). ) Or other physical vapor deposition process (PVD).

The silicon-containing material film may be a silicon oxide film, a silicon nitride film, a metal silicon oxide film, or a metal silicon nitride film. The metal silicon nitride film is not particularly limited, but may be, for example, HfSiNx, ZrSiNx, or TiSiNx. The metal silicon oxide film is not particularly limited, but may be, for example, HfSiOx, ZrSiOx, or TiSiOx.

In order to increase the deposition rate during the deposition process, the substrate may be heated to a temperature of 50 to 500 ℃. To this end and / or thermal energy, plasma or electrical bias can be applied to the substrate such that precursors can be accelerated onto the substrate.

In the deposition process, the precursor may be supplied to the substrate by a bubbling method, a direct gas injection method, a direct liquid injection method, or an organic solution supply method of the precursor. In this case, when the precursor is injected by bubbling method or direct gas injection method, the precursor may be supplied onto the substrate by a flow of one or two or more kinds of mixture gas selected from argon, nitrogen, helium or hydrogen.

When the silicon nitride film or the metal silicon nitride film is deposited, at least one nitrogen-containing reactor selected from ammonia (NH ₃ ), hydrazine (N ₂ H ₄ ), nitrogen dioxide (NO ₂ ) and nitrogen (N ₂ ) may be used as the precursor. Together with the substrate.

Meanwhile, when the silicon oxide film or the metal silicon oxide film is deposited, at least one oxygen-containing reactor selected from water vapor (H ₂ O), oxygen (O ₂ ), and ozone (O ₃ ) is formed on the substrate together with the precursor. Supplied.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. These examples are provided for the purpose of more specifically illustrating embodiments of the invention and are not intended to limit the scope of the invention.

Example

The synthesis of the cyclic aminosilane compounds described in detail below was carried out using the standard vacuum line Schlenk technique, and all synthesis procedures were carried out in an inert atmosphere of nitrogen or argon gas atmosphere.

The morpholine, hexane, trifluorosulfonic acid, phenylsilane, pentane and diclosilane used in the experiment were purchased from Aldrich Inc. and chlorosilane was purchased from REC Silicon Inc. The pentane solvent and the hexane solvent used in the reaction were refluxed with sodium / benzophenone for 24 hours or more in a nitrogen atmosphere and used as a dry anhydrous solvent.

Example  1: according to scheme 5 Morpholinosilane  synthesis

14.1 g of trifluoromethanesulfonic acid in a 500 mL Schlenk flask was added in a nitrogen atmosphere and stirred while lowering the temperature in the flask to -30 ° C. When the temperature in the flask reached -30 ° C, 9.2 g of phenylsilane diluted in 60 ml of pentane was slowly added.

After the temperature in the flask was raised to 0 ° C., 17.4 g of tributylamine was slowly added to the solution obtained above, and 6.7 g of morpholine diluted in 60 ml of diethyl ether was immediately added.

The white salt precipitated when the temperature in the flask was raised to room temperature. Filtration under reduced pressure gave a clear solution. The solution was distilled under reduced pressure to obtain 8.9 g (yield: 90%) of morpholinosilanes. The obtained morpholinosilane was stored in nitrogen because it reacted with moisture in air to form SiO ₂ . The NMR structural analysis of this morpholinosilane was as follows:

¹ H-NMR (400 MHz, benzene- d6 ): 2.7 ppm [4H, morpholine], 3.7 ppm [4H, morpholine], 4.45 ppm [3H, Si-H].

¹³ C-NMR (400 MHz, benzene- d6 ): 46.9 ppm [2C, morpholine], 68.1 ppm [2C, morpholine].

Example  2: according to scheme 3 Morpholinosilane  synthesis

In a 500 mL Schlenk flask, 300 mL of hexane and 18.6 g of morpholine were added in a nitrogen atmosphere, and the temperature in the flask was stirred while lowering the temperature to -10 ° C. When the temperature in the flask reached −10 ° C., 5.7 g of chlorosilane gas was slowly added into the flask. At this time, the HCl gas generated in the reaction and the unreacted morpholine react to precipitate a white salt in the form of a tertiary amine.

After the addition of chlorosilane gas, the temperature in the flask was stirred for 4 hours while maintaining the temperature at -10 ° C, and the temperature in the flask was further stirred for 6 hours while slowly raising the temperature to room temperature. Upon completion of the reaction, the white salt was removed by filtration under reduced pressure to obtain a colorless solution. This colorless solution was fractionated under reduced pressure to obtain 9 g of pure morpholinosilane (yield: 90%). The obtained morpholinosilane was stored in nitrogen because it reacted with moisture in air to form SiO ₂ .

1 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for the morpholinosilanes.

As shown in (A) of FIG. 1, as a result of confirming through GC, morpholinosilane occupied 99%, and it was found that 1% of morpholine not removed was present. In addition, referring to the mass spectrometry data of FIG. 1B, the molecular weight of the synthesized morpholinosilane could be confirmed.

2A and 2B are graphs showing the results of ¹ H-NMR and ¹³ C-NMR structural analysis to confirm the structure of the morpholinosilane, respectively.

Referring to ¹ H-NMR of FIG. 2B, the peaks of three hydrogens (@ chemical shift 4.45 ppm) bound to Si, the peaks of four hydrogens (@ chemical shift 2.77 ppm) and four hydrogens present in the morpholine moiety The peak of (@ chemical shift 3.40 ppm) was confirmed. More specifically, the NMR structural analysis for this morpholinosilane was as follows:

¹ H-NMR (400 MHz, benzene- d6 ): 2.77 ppm [4H, morpholine], 3.40 ppm [4H, morpholine], 4.45 ppm [3H, Si-H].

¹³ C-NMR (400 MHz, benzene- d6 ): 46.9 ppm [2C, morpholine], 68.1 ppm [2C, morpholine].

Example  3: according to scheme 4 Dimorpholinosilane  synthesis

In a 500 mL Schlenk flask, 300 mL of hexane and 43 g of morpholine were added in a nitrogen atmosphere, and the temperature in the flask was stirred while lowering the temperature to -10 ° C. When the temperature in the flask reached −10 ° C., 10 g of dichlorosilane gas was slowly added into the flask. At this time, HCl gas and unreacted morpholine reacted to precipitate a white salt of a tertiary amine form.

After all of the dichlorosilane gas was added, the mixture was stirred for 4 hours while maintaining the temperature in the flask at -10 ° C, and further stirred for 6 hours while slowly raising the temperature in the flask to room temperature. Upon completion of the reaction, the white salt was removed by filtration under reduced pressure to obtain a colorless solution. Fractional distillation of this colorless solution under reduced pressure afforded 18 g of pure dimorpholinosilane (yield: 90%). The resulting dimorpholinosilane was stored in nitrogen because it reacted with moisture in air to form SiO ₂ .

3 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for the dimorpholinosilane.

As shown in (A) of FIG. 3, the purity of the synthesized dimorpholinosilane was 100%. Mass spectrometry using this result showed a molecular weight of 202. As a result, the purity and molecular weight of the synthesized dimorpholinosilane could be confirmed.

4A and 4B are graphs showing the results of ¹ H-NMR and ¹³ C-NMR structural analysis to confirm the structure of the dimorpholinosilanes synthesized in Example 3, respectively.

Referring to the ¹ H-NMR chart of FIG. 4B, peaks of two hydrogen atoms bonded to Si (@ chemical shift 4.45 ppm) and peaks of eight hydrogens present in the morpholine moiety (@ chemical shift 2.77 ppm) and 8 Peaks (@ chemical shift 3.40 ppm) of dogs were found. More specifically, the NMR structural analysis of this dimorpholinosilane was as follows.

¹ H-NMR (400 MHz, benzene- d6 ): 2.77 ppm [8H, morpholine], 3.40 ppm [8H, morpholine], 4.45 ppm [2H, Si-H].

¹³ C-NMR (400 MHz, benzene- d6 ): 46.5 ppm [4C, morpholine], 68.4 ppm [4C, morpholine].

Example  4: according to the following scheme Trimorpholinosilane  synthesis

300 ml of hexane and 10 g of trichlorosilane were added in a nitrogen atmosphere in a 500 mL Schlenk flask. Under stirring the temperature in the flask was lowered to −10 ° C. and 41.81 g of morpholine was added. When the exothermic reaction was completed, the temperature in the flask was raised to room temperature. At this time, the HCl gas generated in the reaction and the unreacted morpholine reacted to precipitate a white salt in the form of a tertiary amine.

After stirring for about 4 hours at room temperature, the reaction was terminated to remove the white salt through filtration under reduced pressure to give a colorless solution. This solution was recrystallized in hexane to obtain 24.27 g (yield 90%) of needle-shaped white solid trimorpholinosilane.

5 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for the trimorpholinosilane.

As shown in FIG. 5A, the purity of the synthesized trimorpholinosilane was 100%. In addition, referring to the mass spectrometry data of FIG. 5B, it was confirmed that the molecular weight of the synthesized trimorpholinosilane was 287 g / mol.

6A and 6B are graphs showing the results of ¹ H-NMR and ¹³ C-NMR structural analysis to confirm the structure of the trimorpholinosilanes synthesized in Example 4, respectively.

Referring to the ¹ H-NMR chart of FIG. 6A, the peak of one hydrogen atom (@ chemical shift 4.26 ppm) bound to Si and the peak of twelve hydrogens (@ chemical shift 2.51 ppm) present in the morpholine moiety and 12 Peaks (@ chemical shift 3.61 ppm) were found. More specifically, the NMR structural analysis of this trimorpholinosilane was as follows.

¹ H-NMR (400 MHz, benzene- d6 ): 2.51 ppm [8H, morpholine], 3.61 ppm [8H, morpholine], 4.26 ppm [H, Si-H].

¹³ C-NMR (400 MHz, benzene- d6 ): 45.5 ppm [4C, morpholine], 68.9 ppm [4C, morpholine].

Example 5 Synthesis of Dithiomorpholinosilanes According to the Reaction Schemes

In a 500 mL Schlenk flask, 300 ml of hexane, 20.4 g of thiomorpholine and 20.0 g of triethylamine were added in a nitrogen atmosphere. The temperature in the flask was lowered to -10 ° C under stirring. When the temperature in the flask reached −10 ° C., 10 g of dichlorosilane gas was slowly added into the flask. At this time, the generated HCl gas and triethyl amine reacted to precipitate a white salt in the form of a tertiary amine.

After all of the dichlorosilane gas was added, the temperature in the flask was further stirred for 4 hours while maintaining the temperature at −10 ° C., and the temperature in the flask was further stirred for 6 hours while slowly raising the temperature to room temperature. Upon completion of the reaction, the white salt was removed by filtration under reduced pressure to obtain a colorless solution. Fractional distillation of this colorless solution under reduced pressure yielded 20.86 g of pure dithiomorpholinosilane (yield: 90%). The obtained dithiomorpholinosilane was stored in nitrogen because it reacted with moisture in air to form SiO ₂ .

7 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for the dithiomorpholinosilane.

As shown in FIG. 7A, the purity of the synthesized dithiomorpholinosilane was found to be 97%. In addition, referring to the mass spectrometry data of FIG. 7B, it was confirmed that the molecular weight of the synthesized dithiomorpholinosilane was 234.46 g / mol.

8 is a graph showing the results of ¹ H-NMR structure analysis for confirming the structure of the dithiomorpholinosilane synthesized in the present embodiment.

Referring to the ¹ H-NMR chart of FIG. 8, peaks of two hydrogen atoms bonded to Si (@ chemical shift 4.35 ppm) and peaks of eight hydrogens present in the morpholine moiety (@ chemical shifts 2.17 ppm) and 8 Hydrogen peaks (@ chemical shift 2.95 ppm) were found. More specifically, the NMR structural analysis of this dithiomorpholinosilane was as follows.

¹ H-NMR (400 MHz, benzene- d6 ): 2.17 ppm [8H, morpholine], 2.95 ppm [8H, morpholine], 4.35 ppm [2H, Si-H].

Example  6: according to the following scheme Of thiomorpholinosilane  synthesis

In a 500 mL Schlenk flask, 300 mL of dimethoxymethane, 10.3 g (0.1 mol) of thiomorpholine and 10.1 g (0.1 mol) of triethylamine were added in a nitrogen atmosphere. The temperature in the flask was lowered to -10 ° C under stirring. When the temperature in the flask reached −10 ° C., 6.7 g (0.1 mol) of monochlorosilane gas was slowly added into the flask. At this time, the generated HCl gas and triethyl amine reacted to precipitate a white salt in the form of a tertiary amine.

After all of the monochlorosilane gas was added, the temperature in the flask was further stirred for 4 hours while maintaining the temperature at −10 ° C., and the temperature in the flask was further stirred for 6 hours while slowly raising the temperature to room temperature. Upon completion of the reaction, the white salt was removed by filtration under reduced pressure to obtain a colorless solution. Fractional distillation of this colorless solution under reduced pressure afforded 11.9 g of pure thiomorpholinosilane (yield: 90%). The thiomorpholinosilane thus obtained was stored under nitrogen because it reacted with moisture in air to form SiO ₂ .

9 is a graph showing gas chromatography-mass spectrometry (GC-MASS) results for the thiomorpholinosilane.

As shown in FIG. 9, the purity of the synthesized thiomorpholinosilane was 96%.

10 is a graph showing the results of ¹ H-NMR structural analysis for confirming the structure of the thiomorpholinosilane synthesized in the present embodiment.

Referring to the ¹ H-NMR chart of FIG. 10, the peaks of three hydrogen atoms bonded to Si (@ 4.3 ppm chemical shift) and the peaks of four hydrogens present in the thiomorpholine moiety (@ 2.7 ppm chemical shift) and Four hydrogen peaks (@ 4.3 ppm chemical shift) were found. More specifically, the NMR structural analysis of this thiomorpholinosilane was as follows.

¹ H-NMR (400 MHz, benzene- d6 ): 2.7 ppm [4H, thiomorpholine], 2.0 ppm [4H, thiomorpholine], 4.3 ppm [3H, Si-H].

Comparative Example  One

Bisdiethylaminosilane (BDEAS), best known as a conventional silicon precursor commercially available from Hansol Chemical, was used for the silicon film deposition test.

Nuclear magnetic resonance NMR Structural analysis

¹ H-NMR and ¹³ C-NMR structural analysis of the compounds synthesized in Examples 1-6 were performed using JEOL JNM-ECS 400 MHz NMR spectrometer ( ¹ H-NMR 400 MHz, ¹³ C-NMR 400 MHz). NMR solvent benzene- d ₆ was used after completely removing residual moisture by stirring with CaH ₂ for one day.

GC - MASS  analysis

Gas chromatography-mass spectrometry of the compounds synthesized in Examples 1-6 was performed using an Agilent 6890 GC & 5973N mass spectrometer. The sample concentration was 1 mg / L = 1 ppm.

Silicon film  Deposition test

The deposition test of the silicon film using the dimorpholinosilane synthesize | combined in Example 3, the dithiomorpholinosilane synthesize | combined in Example 5, and the BDEAS of the comparative example 1 was performed. The conditions of the deposition test of the silicon film were as follows. That is, while maintaining the pressure in the deposition chamber of the vacuum evaporator to 0.2 to 2.0 torr in a vacuum state, while flowing an argon gas into the deposition chamber at a flow rate of 250 sccm, the silicon wafer was heated to 400 ° C. in a state of 300 mm diameter. On the test again, a silicon film was deposited.

Table 3 shows the result of the silicon film formation test using the dimorpholinosilane synthesized in Example 3, the dithiomorpholinosilane synthesized in Example 5, and the BDEAS of Comparative Example 1. Referring to Table 3, the case where the silicon film deposition test using the dimorpholinosilane and the dithiomorpholinosilane obtained in Examples 3 and 5 was performed using BDEAS, which is a silicon precursor currently used in Comparative Example 1 In comparison, the number of pores formed in the silicon film was significantly reduced, and the surface roughness of the silicon film was remarkably low, resulting in a more uniform silicon film. Specifically, in the case of the BDEAS of Comparative Example 1, there are 10 pores having a size of about 15 nm per 30 cells, whereas in the case of the dimorpholinosilane of Example 3, only two of about 15 nm are present, It was confirmed that no morpholinosilane was present at all. In addition, the BDEAS of Comparative Example 1 had a surface roughness of about 0.35 nm, while the dimorpholinosilanes and dithiomorpholinosilanes of Examples 3 and 5 had surface roughness of 0.249 nm and 0.214 nm, respectively. Could. From this, it was confirmed that the cyclic aminosilane compound including the oxygen atom or the sulfur atom and the nitrogen atom together in one ring is a silicon precursor superior to the chain amino silane compound.

Here, the pores represent voids formed in the silicon film when the silicon film is deposited on the silicon wafer using the silicon precursor, and the smaller the number of pores, the better the silicon precursor. In addition, the surface roughness represents a roughness formed on the surface of the silicon film when the silicon film is deposited using the silicon precursor on the silicon wafer, and the smaller the surface roughness value, the better the silicon precursor.

Pore count

Scannig Electron Microscopy (SEM) for each of the dimorpholinosilanes synthesized in Example 3, the dithiomorpholinosilanes synthesized in Example 5, and the silicon film deposited using the BDEAS of Comparative Example 1 It was confirmed how many pores of about 15 nm size per 30 cells.

Surface roughness  How to measure

The dimorpholinosilanes synthesized in Example 3, the dithiomorpholinosilanes synthesized in Example 5, and the silicon films deposited using the BDEAS of Comparative Example 1 are shown in Table 2 below at five positions. Surface roughness was measured using Atomic Force Microscopy (AFM), and the average value was summarized in Table 3 as surface roughness. At this time, the (X, Y) coordinate of the center point of the 300 mm diameter wafer was set to (0,0).

Measuring point X coordinate (mm) Y coordinate (mm) Center point 0 0 Upper point 0 145 Left point -145 0 Bottom point 0 -145 Right point 145 0

Comparative Example 1 Example 3 Example 5 Compound name Bisdiethylaminosilane
(BDEAS) Dimorpholinosilane Dithiomorpholinosilane compound
Chemical structure

Pore count
(30 cells)
10 @ 15 nm 2 @ 15 nm 0 @ 15 nm Surface roughness
(nm) 0.35 0.249 0.214

From the above results, a cyclic ring containing oxygen atoms or sulfur atoms and nitrogen atoms together or containing two nitrogen atoms in one ring according to the present invention, which is characterized by a new type of silicon precursor having a low molecular weight and a high boiling point. The aminosilane compound is very excellent in affinity and bonding strength with substructures containing silicon atoms such as silicon wafers or containing metal atoms. Therefore, by forming the silicon film or the silicon-containing material film using the cyclic aminosilane compound according to the present invention it is possible to obtain a uniform film on the surface of the substructure at a high speed.

M / Z: ratio of mass / charge
δ: chemical shift

Claims (12)

delete A cyclic aminosilane compound represented by any one of the following formulas (1) to (4):

In the above formula, n and m are each independently an integer of 0 to 5, X is a sulfur atom, R ₁ and R ₂ are each independently a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, C6-C12 It is an aryl group, a vinyl group, or an allyl group. The cyclic aminosilane compound according to claim 2, wherein the cyclic aminosilane compound is dithiomorpholinosilane represented by the following formula (8) or thiomorpholinosilane represented by the formula (9):

. A ring including both a sulfur atom and a nitrogen atom in one ring by reaction of a halogenated silane compound (A) with a cyclic amine compound (B) including both a sulfur atom and a nitrogen atom in one ring according to Scheme 1 below. A process for preparing a cyclic aminosilane compound comprising the step of obtaining the type aminosilane compound (1), (2), (3), or (4):
[Reaction Scheme 1]

Wherein A, B, C, and D are each independently F, Cl, Br, I or a hydrogen atom, n and m are each independently an integer from 0 to 5, X is a sulfur atom, R ₁ and R ₂ is each independently a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, a C6-C12 aryl group, a vinyl group or an allyl group. The method according to claim 4, wherein the chemical reaction according to Scheme 1 takes place in an organic solvent, the organic solvent is C4 to C10 alkanes, C4 to C10 cycloalkanes, C6 to C8 aromatic hydrocarbons, C2 to C10 aliphatic ethers, C4 to C10 rings A method for producing a cyclic aminosilane compound, characterized in that the aliphatic ether, or a mixture thereof. The cyclic aminosilane compound according to claim 4, wherein the halogenated silane compound (A) is a silane compound substituted with chlorine represented by the following formulas (C), (D), (E) or (F): Manufacturing method of:

. After reacting phenylsilane with trifluoromethanesulfonic acid to obtain silyl triflate, the silyl triflate is combined with the following cyclic amine compound (B) containing a sulfur atom and a nitrogen atom in one ring. A method for producing a cyclic aminosilane compound comprising the step of reacting to obtain the following cyclic aminosilane compound (1):

,

.
In the above formula, n and m are each independently an integer of 0 to 5, X is a sulfur atom, R ₁ and R ₂ are each independently a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, C6-C12 It is an aryl group, a vinyl group, or an allyl group. As a thin film formation method,
A method of forming a thin film comprising forming a silicon film or a silicon-containing material film on a substrate by a deposition process using a cyclic aminosilane compound represented by any one of the following Formulas (1) to (4):

In the above formula, n and m are each independently an integer of 0 to 5, X is a sulfur atom, R ₁ and R ₂ are each independently a hydrogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, C6-C12 It is an aryl group, a vinyl group, or an allyl group. delete The method for forming a thin film according to claim 8, wherein the cyclic aminosilane compound is dithiomorpholinosilane represented by the following general formula (8) or thiomorpholinosilane represented by the general formula (9):

. The method of claim 8, wherein the deposition process is an atomic layer deposition process (ALD) or a chemical vapor deposition process (CVD). The method of claim 8, wherein the material film containing silicon is a polysilicon film, a silicon oxide film, a silicon nitride film, a metal silicon oxide film, or a metal silicon nitride film.


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