Silicon Precursor Compound, Preparation Method Thereof, and Preparation Method of Silicon-Containing Thin Film Using the Silicon Precursor

Abstract

The present invention relates to a novel silicon precursor compound capable of preparing a silicon-containing thin film of excellent quality, a method for preparing the same, and a method for preparing a silicon-containing thin film using the silicon precursor compound.

Description

Technical Field

[0001] The present invention relates to a silicon precursor compound, a method for preparing the same, and a method for preparing a silicon-containing thin film using the silicon precursor compound.

Background Art

[0002] Silicon-containing thin films such as films of silicon oxide, silicon nitride, silicon oxynitride, and silicon carbonitride are essential thin films for the operation of microelectronic devices such as semiconductors and non-semiconductors (logic).

[0003] In recent years, with the high integration of semiconductor devices, silicon-containing thin films having various performances have been demanded. Along with the high integration of semiconductor devices, as the aspect ratio increases, there has been a problem that the deposition of silicon-containing thin films using conventional silicon precursor compounds cannot satisfy the required performance.

[0004] Atomic layer deposition (ALD) or chemical vapor deposition (CVD) is widely used for preparing silicon-containing thin films. Among these, atomic layer deposition (ALD) is a method of sequentially supplying a silicon compound gas and a reaction gas necessary for film formation, and has an advantage that a silicon-containing thin film having a uniform thickness can be formed even on a surface with large irregularities. For this reason, atomic layer deposition (ALD) is widely used.

[0005] The mechanisms of chemical vapor deposition (CVD) and atomic layer deposition (ALD) are different from each other. Silicon precursors used for the preparation of silicon-containing thin films are diverse according to various process conditions and their physical and chemical properties.

Summary of the Invention

Problems to be Solved by the Invention

[0006] An object of the present invention is to provide a novel silicon precursor compound and a method for preparing the same, which are advantageous for preparing a silicon-containing thin film of excellent quality.

[0007] Another object of the present invention is to provide a method for preparing a silicon-containing thin film using such a silicon precursor compound.

Means for Solving the Problems

[0008] The silicon precursor compound of the present invention for achieving the above object is characterized by being represented by the following formula 1.

[0009]

Chemical formula

[0010] The silicon precursor compound of the present invention is preferably selected from the following compounds (1) to (36).

Chemical formula

Chemical formula

[0011] The method for preparing the silicon precursor compound of the present invention may include a first step of reacting a chlorosilane derivative with a primary amine to form a first compound, a second step of reacting the first compound with an alkyl-lithium (alkyl-Li) to form a second compound containing lithium, and a third step of reacting the second compound with a silane compound to prepare a silicon precursor compound represented by formula 1.

[0012] The first compound is preferably a compound represented by the following formula 7.

[0013]

Chemical formula

[0014] In formula 7, R 0 is each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, and R 2 , R 3 and R 4 are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms.

[0015] In the method for preparing the silicon precursor compound of the present invention, when X and R 1 in the silicon precursor compound represented by formula 1 are each a halogen, the reaction may include a fourth step of reacting it with a metal hydride (MH).

[0016] In the method for preparing the silicon precursor compound of the present invention, the silane compound can be produced by reacting a chlorosilane derivative with a secondary amine.

[0017] The silicon precursor compound of formula 1 prepared by the method for preparing the silicon precursor compound of the present invention is selected from the above compounds (1) to (36).

[0018] To achieve other objects, the method for preparing a silicon-containing thin film according to the present invention can form a silicon-containing thin film using the silicon precursor compound represented by the above formula 1.

[0019] In the method for preparing the silicon-containing thin film of the present invention, the silicon precursor compound is preferably selected from the above compounds (1) to (36).

[0020] In a method for preparing a silicon-containing thin film according to the present invention, the silicon-containing thin film can be deposited by chemical vapor deposition (CVD) or atomic layer deposition (ALD). The atomic layer deposition in the present invention may include plasma-enhanced atomic layer deposition.

[0021] The silicon-containing thin film may be any one selected from the group consisting of a silicon oxide film (SiO 2 ), a silicon oxycarbide film (SiOC), a silicon nitride film (SiN), a silicon oxynitride film (SiON), a silicon carbonitride film (SiCN), and a silicon carbide film (SiC).

[0022] The silicon-containing thin film according to the present invention can be formed at a temperature of about 500 °C or lower.

[0023] According to one embodiment of the method for preparing the silicon-containing thin film of the present invention, the silicon oxide film (SiO 2 ) can be formed by atomic layer deposition. Atomic layer deposition according to one embodiment includes providing a substrate in a reactor, introducing a silicon precursor compound according to the present invention into the reactor, purging the reactor with a purge gas, introducing an oxygen source into the reactor to react with the silicon precursor compound according to the present invention to form a silicon oxide film, and purging the reactor with a purge gas.

[0024] The purge gas according to one embodiment is used to remove unconsumed reactants and reaction by-products, and is preferably selected from the group consisting of nitrogen, helium, argon, and mixtures thereof, but is not limited thereto.

[0025] The oxygen source according to one embodiment is preferably selected from the group consisting of oxygen, peroxide, oxygen plasma, water vapor, water vapor plasma, hydrogen peroxide, ozone source, and mixtures thereof, but is not limited thereto. Preferably, the oxygen source may include plasma, and the plasma may be generated in situ.

[0026] In addition, atomic layer deposition according to one embodiment can be carried out at one or more temperatures of about 500 °C or lower. In such a case, the lower limit of the temperature can be appropriately selected by those skilled in the art according to the type of oxygen source used. Preferably, the silicon oxide film can be formed at one or more temperatures of about 300 °C to 500 °C.

[0027] According to another embodiment of the method for preparing the silicon-containing thin film of the present invention, the silicon nitride film (SiN) can be formed by plasma-enhanced atomic layer deposition. Atomic layer deposition according to one embodiment includes providing a substrate in a reactor, introducing a silicon precursor compound according to the present invention into the reactor, purging the reactor with a purge gas, introducing a nitrogen-containing plasma source and an inert gas into the reactor to react with the silicon precursor compound according to the present invention to form a silicon nitride film, and purging the reactor with a purge gas.

[0028] The purge gas according to one embodiment is used to remove unconsumed reactants and reaction by-products, and is preferably selected from the group consisting of nitrogen, helium, argon, and mixtures thereof, but is not limited thereto.

[0029] The nitrogen-containing plasma source according to one embodiment is preferably selected from the group consisting of nitrogen plasma, nitrogen and argon mixed plasma (nitrogen / argon plasma), ammonia plasma, nitrogen and ammonia mixed plasma (nitrogen / ammonia plasma), ammonia and helium mixed plasma (ammonia / helium plasma), ammonia and argon mixed plasma (ammonia / argon plasma), ammonia and nitrogen mixed plasma (ammonia / nitrogen plasma), NF 3 plasma, organic amine plasma, and mixtures thereof, but is not limited thereto.

[0030] In addition, plasma-enhanced atomic layer deposition according to one embodiment can be carried out at one or more temperatures of about 400 °C or lower. In such a case, the lower limit of the temperature can be appropriately selected by those skilled in the art according to the type of nitrogen-containing plasma source used. Preferably, the silicon nitride film can be formed at one or more temperatures of about 150 °C to 350 °C, more preferably at a temperature of about 250 °C.

Advantages of the Invention

[0031] The silicon precursor compound of the present invention exhibits sufficient volatility to be applicable to both atomic layer deposition (ALD) and chemical vapor deposition (CVD) for preparing silicon-containing thin films. In particular, since deposition is possible at high temperatures and the deposition rate is high, there is an effect that a high-quality silicon-containing thin film can be prepared.

[0032] However, the effects of the present invention are not limited to the above.

Brief Description of the Drawings

[0033]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0034] Hereinafter, the silicon precursor compound according to the present invention, a method for preparing the same, and a method for preparing a silicon-containing thin film using the silicon precursor compound will be described in detail.

[0035] In this specification, the term "about" is intended to encompass ±5% of the defined number.

[0036] The silicon precursor compound of the present invention can be represented by the following formula 1.

[0037]

Chemical formula

[0038] In formula 1, R 0 , R 5 and R 6 are each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, and R 1 , R 2 , R 3 and R 4 are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, and X is hydrogen (H) or a halogen.

[0039] R 0 , R 1 , R 2 , R 3 , R 4 , R5 and R 6 The hydrocarbon groups in are each independently any one selected from the group consisting of a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, and isomers thereof.

[0040] The halogen may be any one selected from the group consisting of chlorine (Cl), bromine (Br), iodine (I), and fluorine (F). Among the above, chlorine (Cl) is preferred.

[0041] Specifically, R 0 is any one selected from a methyl group (Me), an ethyl group (Et), and an iso-propyl ( iso Pr), and R 1 , R 2 , R 3 and R 4 are each independently any one selected from hydrogen (H), chlorine (Cl), and a methyl group (Me), and R 5 and R 6 are each independently a methyl group (Me) or an ethyl group (Et), and X is preferably hydrogen (H) or chlorine (Cl).

[0042] The silicon precursor compound of the present invention can be prepared by a method as shown in the following Reaction Scheme 1 or Reaction Scheme 2.

[0043]

Chemical formula

[0044] The method for preparing a silicon precursor compound according to Reaction Scheme 1 can be carried out in the order of a first step of reacting a chlorosilane derivative represented by Formula 5 with a primary amine represented by Formula 6 to form a first compound represented by Formula 7, a second step of reacting the first compound with an alkyl-lithium (alkyl-Li) to form a second compound represented by Formula 8, and a third step of reacting the second compound with a silane compound represented by Formula 4 to prepare a silicon precursor compound represented by Formula 1.

[0045] As used herein, the first compound and the second compound are terms used only for the purpose of distinguishing the compounds formed in each step of the method for preparing a silicon precursor compound.

[0046] In the first step of the method for preparing a silicon precursor, a triorganochlorosilane, which is a chlorosilane derivative, is reacted with a primary amine at a low temperature of about -40 °C in a nonpolar solvent to carry out a substitution reaction between Cl and the amine, followed by filtration and distillation under reduced pressure to form a compound of Formula 7.

[0047] In the second step, the compound of Formula 7 formed in the first step is reacted with an alkyl-lithium (alkyl-Li) at a low temperature of about -40 °C in a nonpolar solvent to carry out a Li substitution reaction to form a compound of Formula 8.

[0048] Alkyl-Li is lithium having an alkyl group with 1 to 10 carbon atoms. Examples thereof include methyl lithium, ethyl lithium, propyl lithium, butyl lithium, and isobutyl lithium.

[0049] In the third step, after reacting with a silane compound represented by Formula 4 to form a silicon precursor compound represented by Formula 1, the reaction product salts (LiCl) and unreacted substances are removed by filtration, and then distilled under reduced pressure to obtain a silicon precursor compound represented by Formula 1.

[0050] Another method for preparing the silicon precursor compound according to Reaction Scheme 2 can be carried out in the same manner as Reaction Scheme 1. X and R in the silicon precursor compound represented by Formula 1' of Reaction Scheme 2 1 When each is a halogen selected from fluorine (F), chlorine (Cl), bromine (Br), or iodine (I), a fourth step of reacting with a metal hydride (MH) as a reducing agent is further carried out.

[0051] The metal hydride (MH) may be at least one selected from lithium hydride (LiH), sodium hydride (NaH), lithium borohydride (LiBH 4 ), lithium aluminum hydride (LiAlH 4 ), sodium aluminum hydride (NaAlH 4 ), and sodium borohydride (NaBH 4 ). For example, lithium hydride (LiH) which is a metal hydride (MH) can be used by reacting it with tetrahydrofuran (THF).

[0052] Preferably, the fourth step is carried out when X and R of Formula 1' 1 are chlorine (Cl).

[0053] In the method for preparing the silicon precursor compound according to Reaction Scheme 1 or 2, as shown in the following Reaction Scheme 3, a chlorosilane derivative represented by Formula 2 is reacted with a secondary amine of Formula 3 at a low temperature of about -40 °C in a non-polar solvent, and after a substitution reaction of Cl and the amine, it is filtered and distilled under reduced pressure to form a compound of Formula 4.

[0054]

Chemical formula

[0055] In the formulas of Reaction Schemes 1 to 3, R 0 , R 5 and R 6 are each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, R1 , R 2 , R 3 and R 4 are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, and X is hydrogen (H) or a halogen.

[0056] Preferably, in the formula of Reaction Scheme 1, R 0 may be any one selected from a methyl group (Me), an ethyl group (Et), and an iso-propyl ( iso Pr), and R 1 , R 2 , R 3 and R 4 are each independently may be any one selected from hydrogen (H), chlorine (Cl), and a methyl group (Me), and R 5 and R 6 are each independently may be a methyl group (Me) or an ethyl group (Et), and X may be hydrogen (H) or chlorine (Cl).

[0057] As the non-polar solvent used in Reaction Schemes 1 to 3, hexane, n-pentane, etc. can be used, but it is not limited thereto. A non-polar solvent generally used by those skilled in the art can be used.

[0058] As a preferred example, the silicon precursor compound of the present invention is selected from the following compounds (1) to (36).

Chemical formula

Chemical formula

[0059] In addition, in the method for preparing the silicon-containing thin film of the present invention, a silicon-containing thin film can be formed by chemical vapor deposition (CVD) or atomic layer deposition (ALD) using the silicon precursor compound represented by Formula 1.

[0060] The silicon-containing thin film can be formed as any one selected from the group consisting of a silicon oxide film (SiO 2 ), a silicon oxycarbide film (SiOC), a silicon nitride film (SiN), a silicon oxynitride film (SiON), a silicon carbonitride film (SiCN), and a silicon carbide film (SiC).

Example

[0061] Hereinafter, the present invention will be described in more detail with reference to examples.

[0062] [Example 1] First, regarding 1-chloro-diethylamino-methylsilazane as a silane compound necessary for the preparation of a silicon precursor compound, 217 g (1.89 mol) of dichloromethylsilane (CH 3 SiHCl 2 ) and 2,722 g (20 mol) of n-pentane were placed in a 1-liter flask in an anhydrous inert atmosphere. While maintaining the temperature at -40°C, 283 g (3.87 mol) of diethylamine ((CH 3 CH 2 )) 2 NH) was gradually added, and then stirred for 3 hours. After the stirring was completed, diethylamine hydrochloride ((CH 3 CH 2 )) 2 NH 3 Cl) was removed by filtration, and 220 g (1.45 mol) of chlorodiethylaminomethylsilazane ((CH 3 CH 2 )) 2 NCH 3 SiHCl) (yield: 77%) was obtained by distillation under reduced pressure. 1 H NMR (C 6 D 6 ): δ 0.28 (s, 3H (-SiCH 3 )), 0.86 (m, 6H (-(N(CH 2 CH 3 )) 2 ), 2.69 (m, 4H (-N(CH 2 CH 3 )) 2 ), 5.07 (m, 1H (-SiH))

[0063] In the first step, isopropylaminotrimethylsilazane was prepared. In a 1-liter flask under an anhydrous inert atmosphere, 220 g (2.03 mol) of chlorotrimethylsilane ((CH 3 ) 3 SiCl) and 2,190 g (30 mol) of n-pentane were placed. While maintaining the temperature at -40°C, 251 g (4.25 mol) of isopropylamine ((CH 3 ) 2 CHNH 2 ) was gradually added, and then the mixture was stirred for 3 hours. After completion of stirring, isopropylamine hydrochloride ((CH 3 ) 2 CHNH 3 Cl) was removed by filtration, and then the product was distilled under reduced pressure to obtain 205 g (1.5 mol) of isopropylaminotrimethylsilazane ((CH 3 ) 2 CHNHSi(CH 3 ) 3 )(yield: 77%). 1 1H NMR (C 6 D 6 ): δ 0.06 (s, 6H (SiCH 3 )) 3 , 0.96 (d, 6H (NCH(CH 3 )) 2 ), 2.92 (m, 1H (NCH(CH 3 )) 2 )

[0064] In the second step, in a 1-liter flask under an anhydrous inert atmosphere, 161 g (1.11 mol) of isopropylaminotrimethylsilazane ((CH 3 ) 2 CHNHSi(CH 3 ) 3 ) prepared in the first step and 950 g (11.0 mol) of hexane were placed. While maintaining the temperature at -40°C, 470 mL (1.17 mol) of 2.5 M n-butyllithium (n-BuLi) was gradually added. Then, the reaction solution was gradually warmed to room temperature and stirred at room temperature for 12 hours. While maintaining the temperature of the mixed solution at -20°C again, 1-chloro-diethylamino-methylsilazane ((CH3 CH 2 ) 2 NCH 3 168 g (1.11 mol) of SiHCl was gradually added, and the mixture was stirred for 6 hours or more. After completion of stirring, lithium chloride (LiCl) salt was removed by filtration. The obtained filtrate was distilled under reduced pressure to obtain 190 g (yield: 70%) of diethylaminoisopropyltetramethyldisilazane ((CH 3 CH 2 ) 2 NCH 3 HSiNCH(CH 3 ) 2 Si(CH 3 ) 3 )), which is a silicon precursor compound.

[0065] Figure 1 shows the hydrogen nuclear magnetic resonance ( 1 H-NMR) spectrum of the silicon precursor compound prepared according to Example 1 of the present invention. As shown in Figure 1, it was confirmed that the silicon precursor compound prepared in Example 1 was diethylaminoisopropyltetramethyldisilazane. 1 H NMR(C 6 D 6 ): δ 0.20 (s, 9H (-Si(CH 3 ) 3 ), 0.25 (d, 3H (-SiHCH 3 )), 0.99 (m, 6H (-SiN(CH 2 CH 3 ) 2 ), 1.18 (m, 6H (-NCH(CH 3 ) 2 ), 2.83 (m, 4H (-SiN(CH 2 CH 3 ) 2 ), 3.25 (m, 1H (-NCH(CH 3 ) 2 ), 4.96 (m, 1H (-SiH))

[0066] [Example 2] In Example 2, dimethylaminoisopropyltetramethyldisilazane of compound (13) was prepared as the silicon precursor compound.

[0067] First, regarding chloro-dimethylamino-methylsilazane as a silane compound necessary for the preparation of a silicon precursor compound, 400 g (3.48 mol) of dichloromethylsilane (CH 3 SiHCl 2 ) and 4,516 g (62.59 mol) of n-pentane were placed in a 1-liter flask under an anhydrous inert atmosphere. While maintaining the temperature at -40°C, 313 g (6.95 mol) of dimethylamine ((CH 3 ) 2 NH) was gradually added, and then the mixture was stirred for 3 hours. After completion of stirring, dimethylamine hydrochloride ((CH 3 ) 2 NH 3 Cl) was removed by filtration, and 320 g (2.59 mol) of chlorodimethylaminomethylsilazane ((CH 3 ) 2 NCH 3 SiHCl) (yield: 74%) was obtained by distillation under reduced pressure. 1 H NMR (C 6 D 6 ): δ 0.23 (d, 3H (-SiCH 3 )), 2.25 (m, 6H (-(N(CH 3 ) 2 )), 5.0 (m, 1H (-SiH))

[0068] In the first step of Example 2, isopropylaminotrimethylsilazane was prepared in the same manner as in Example 1.

[0069] In the second step of Example 2, in a 1-liter flask under an anhydrous inert atmosphere, isopropylaminotrimethylsilazane ((CH 3 ) 2 CHNHSi(CH 3 ) 3)220 g (1.51 mol) and 1,304 g (15.1 mol) of hexane were added. While maintaining the temperature at -40 °C, 641 mL (1.59 mol) of 2.5 M n-butyllithium (n-BuLi) was gradually added. Then, the reaction solution was gradually warmed to room temperature and stirred at room temperature for 12 hours. While maintaining the temperature of the mixed solution at -20 °C again, 187 g (1.51 mol) of chloro-dimethylamino-methylsilazane ((CH 3 ) 2 NCH 3 SiHCl) was gradually added, and then stirred for 6 hours or more. After completion of stirring, lithium chloride (LiCl) salt was removed by filtration. The obtained filtrate was distilled under reduced pressure to obtain 231 g (yield: 70%) of dimethylaminoisopropyltetramethyldisilazane ((CH 3 ) 2 NCH 3 HSiNCH(CH 3 ) 2 Si(CH 3 ) 3 ) which is a silicon precursor compound.

[0070] Figure 2 shows the hydrogen nuclear magnetic resonance ( 1 H-NMR) spectrum of the silicon precursor compound prepared according to Example 2 of the present invention. As shown in Figure 2, it was confirmed that the silicon precursor compound prepared in Example 2 is dimethylaminoisopropyltetramethyldisilazane. 1 H NMR(C 6 D 6 ): δ 0.16 (s, 9H (-Si(CH 3 ) 3 ), 0.22 (d, 3H (-SiHCH 3 )), 1.13 (m, 6H (-NCH(CH 3 ) 2 )), 2.41 (s, 6H (-SiN(CH 3 ) 2 ),) 3.17 (m, 1H (-NCH(CH 3 ) 2 )), 4.88 (m, 1H (-SiH))

[0071] [Example 3] In Example 3, as the silicon precursor compound, chloro-isopropyl-dimethyl-(trimethylsilyl) silane diamine of compound (16) was prepared.

[0072] First, regarding dichloro-dimethylsilane amine as the silane compound necessary for the preparation of the silicon precursor compound, trichloromethylsilane (SiHCl 3 ) 400 g (2.95 mol) and n-pentane 4,200 g (59.0 mol) were placed in a 1-liter flask under an anhydrous inert atmosphere. While maintaining the temperature at -40°C, 266 g (5.91 mol) of dimethylamine ((CH 3 ) 2 NH) was gradually added, and then stirred for 3 hours. After completion of stirring, dimethylamine hydrochloride ((CH 3 ) 2 NH 3 Cl) was removed by filtration, and dichloro-dimethylsilane amine ((CH 3 ) 2 NSiHCl 2 ) 297 g (2.07 mol) (yield: 70%) was obtained by distillation under reduced pressure. 1 H NMR (C 6 D 6 ): δ 2.25 (s, 6H (-N(CH 3 ) 2 )), 5.28 (m, 1H (-SiH))

[0073] In the first step of Example 3, isopropylaminotrimethylsilazane was prepared in the same manner as in Example 1.

[0074] In the second step of Example 3, in a 1-liter flask under an anhydrous inert atmosphere, isopropylaminotrimethylsilazane ((CH 3 ) 2 CHNHSi(CH 3 ) 3)200 g (1.38 mol) and 593 g (6.88 mol) of hexane were added. While maintaining the temperature at -40 °C, 402 mL (1.45 mol) of 2.5 M n-butyllithium (n-BuLi) was gradually added. Then, the reaction solution was gradually warmed to room temperature and stirred at room temperature for 12 hours. While maintaining the temperature of the mixed solution at -20 °C again, 198 g (1.38 mol) of dichlorodimethylsilane ((CH 3 ) 2 NSiHCl 2 ) was gradually added and then stirred for 6 hours or more. After completion of stirring, lithium chloride (LiCl) salt was removed by filtration. The obtained filtrate was distilled under reduced pressure to obtain 197 g (yield: 60%) of chloro-isopropyl-dimethyl-(trimethylsilyl) silanediamine ((CH 3 ) 2 NHClSiNCH(CH 3 ) 2 Si(CH 3 ) 3 ) which is a silicon precursor compound. 1 H NMR (C 6 D 6 ): δ 0.16 (s, 9H (-Si(CH 3 ) 3 ), 1.15 (m, 6H (-NCH(CH 3 ) 2 ), 2.40 (s, 6H (-SiN(CH 3 ) 2 ), 3.20 (m, 1H (-NCH(CH 3 ) 2 ), 5.37 (m, 1H (-SiH))

[0075] [Example 4] In Example 4, isopropyldimethyltrimethylsilylsilanediamine of compound (19) was prepared as the silicon precursor compound.

[0076] First, chloro-isopropyl-dimethyl-(trimethylsilyl) silanediamine ((CH 3 ) 2 NHClSiNCH 2 (CH 3 ) required for the preparation of the silicon precursor compound2 Si(CH 3 ) 3 ) was prepared in the same manner as in Example 3.

[0077] To a 1-liter flask in an anhydrous inert atmosphere, 3.5 g (0.44 mol) of LiH and 452 g (6.28 mol) of tetrahydrofuran were added. While maintaining the temperature at 0 °C, chloro-isopropyl-dimethyl-(trimethylsilyl) silane diamine ((CH 3 ) 2 NHClSiNCH 2 (CH 3 ) 2 Si(CH 3 ) 3 ) 100 g (0.42 mol) was gradually added. Then, the temperature was gradually raised to room temperature and stirred at 67 °C for 12 hours. After completion of stirring, lithium chloride (LiCl) salt was removed by filtration. The obtained filtrate was purified by distillation under reduced pressure to obtain 59 g of isopropyl dimethyl trimethylsilyl silane diamine ((CH 3 ) 2 NH 2 SiNCH(CH 3 ) 2 Si(CH 3 ) 3 )(yield: 70%). 1 H NMR(C 6 D 6 ): δ 0.16 (s, 9H (-Si(CH 3 )) 3 ), 1.14 (d, 6H (-NCH(CH 3 )) 2 ), 2.42 (s, 6H (-SiN(CH 3 )) 2 ), 3.19 (m, 1H (-NCH(CH 3 )) 2 ), 4.80 (s, 2H (-SiH 2 ))

[0078] Thermogravimetric analysis (TGA) was performed to analyze the thermal properties of the silicon precursor compounds prepared in Examples 1 and 2. The results are shown in Figure 3.

[0079] As shown in FIG. 3, the silicon precursor compounds of Example 1 exhibit volatility in various temperature ranges of 200° C. or lower, 200° C. to 500° C., and 500° C. or higher. In particular, the silicon precursor compound of Example 2 exhibits volatility in temperature ranges of 160° C. or lower, 160° C. to 500° C., and 500° C. or higher, which are lower than those of Example 1. Therefore, these are excellent silicon precursors capable of forming silicon-containing oxide thin films and silicon-containing nitride thin films in a wide temperature range.

[0080] The above results indicate that all the silicon precursor compounds prepared according to Examples 1 and 2 exhibit sufficient volatility for application to atomic layer deposition (ALD) or chemical vapor deposition (CVD).

[0081] In order to confirm that the silicon precursor compounds prepared according to Examples 1 and 2 have a vapor pressure suitable for the preparation of silicon nitride thin films by a deposition method, their vapor pressures were measured. The results are shown in FIG. 4.

[0082] As shown in FIG. 4, both the silicon precursor compounds of Examples 1 and 2 exhibited a high vapor pressure of 10 Torr at about 100° C. In particular, Example 2 exhibited a higher vapor pressure at a lower temperature than Example 1.

[0083] The above vapor pressure results indicate that the silicon precursor compounds prepared according to Examples 1 and 2 both exhibit a high vapor pressure at a low temperature of about 100° C. or lower and exhibit a sufficient vapor pressure for application to atomic layer deposition (ALD) or chemical vapor deposition (CVD).

[0084] To evaluate the silicon-containing thin film formed using the silicon precursor compound prepared according to the present invention, a silicon nitride thin film was deposited on a silicon substrate by atomic layer deposition (ALD) using diethylaminoisopropyltetramethyldisilazane of Example 1 as the silicon precursor compound. In such a case, an ALD reactor using a double showerhead to separately supply the silicon precursor compound and the reactive gas in the vertical direction was used.

[0085] Table 1 and FIG. 9 show the specific conditions for depositing the silicon nitride thin film.

[0086]

Table 1

[0087] The thickness of the thin film deposited in this way was measured with an ellipsometer. Table 2 and FIG. 6 show the results of analyzing the characteristics of a specific silicon nitride thin film.

[0088]

Table 2

[0089] As shown in Table 2, when the substrate temperature was 250°C, the deposition rate was faster and the film thickness was thicker than when the substrate temperature was 350°C. Therefore, it can be seen that a high deposition rate was obtained at a lower temperature, and when the N / Si composition ratio was examined, a silicon-containing thin film with high purity was formed. Also, FIG. 6 is a graph showing the deposition rate of the silicon nitride thin film with respect to the substrate temperature. As shown in FIG. 6, the deposition rate was the same under the conditions of 250°C and 350°C.

[0090] As another example, to evaluate the silicon oxide film (SiO 2 ) formed using the silicon precursor compound prepared according to the present invention, dimethylaminoisopropyltetramethyldisilazane of Example 2 was used as the silicon precursor compound, and a silicon oxide film was deposited on a silicon substrate by atomic layer deposition (ALD). In such a case, an atomic layer deposition (ALD) reactor that separately supplies the silicon precursor compound and the reactive gas vertically using a double showerhead was used.

[0091] In this specification, SiN and SiO, which are silicon-containing thin films, are described as representative examples 2 , but the present invention is not limited thereto. SiN, SiO 2, silicon-containing thin films known in the art such as SiOC, SiON, SiCN, and SiC can be formed.

[0092] Specific conditions for silicon oxide film deposition are shown in Table 3 and Figure 7.

[0093]

Table 3

[0094] The composition of the silicon oxide film was analyzed using X-ray photoelectron spectroscopy (XPS) of the thin film deposited by the above method, and the step coverage was confirmed using a transmission electron microscope (TEM). Tables 4, 8, and 9 show the results of analyzing the characteristics of a specific silicon oxide film.

[0095]

Table 4

[0096] As shown in Table 4, the silicon oxide film formed using the silicon precursor compound of Example 2 was 90 Å thick. When the O / Si composition ratio was examined, a high-purity silicon-containing thin film was formed.

[0097] Figure 8 is a transmission electron microscope (TEM) photograph of a silicon oxide film deposited at a substrate temperature of 400 °C. As shown in Figure 8, the silicon oxide film was uniformly formed with a thickness of 90 Å.

[0098] Figure 9 is a graph showing the deposition rate of the silicon oxide film with respect to the substrate temperature. As shown in Figure 9, the deposition rate was similar in the temperature ranges of 300 °C and 500 °C.

[0099] Figure 10 shows the composition of a silicon oxide film deposited at a substrate temperature of 400 °C, analyzed using X-ray photoelectron spectroscopy (XPS).

[0100] As described above, the cyclodisilazane derivative as a silicon precursor compound prepared according to the present invention is suitable for forming a high-purity silicon-containing thin film at a high deposition rate by atomic layer deposition (ALD).

[0101] The above-described embodiments are merely for explaining the preferred embodiments of the present invention. The scope of the present invention is not limited to the described embodiments. Those skilled in the art will be able to make various changes, modifications, and substitutions within the technical idea and scope of the claims of the present invention. It should be understood that such embodiments are within the scope of the present invention.

Claims

1. The following formula 1: 【Chemical 1】 (In Formula 1, R ０ , R ５ and R ６ are each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, and R １ , R ２ , R ３ and R ４ are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, and X is hydrogen (H) or a halogen), a silicon precursor compound represented by

2. The following compounds (1) to (36): 【Chemical 2】 [Chemical Formula 3] The silicon precursor compound according to claim 1, selected from

3. A method for preparing a silicon precursor compound, comprising: a first step of reacting a chlorosilane derivative with a primary amine to form a first compound; a second step of reacting the first compound with an alkyl-lithium (alkyl-Li) to form a second compound containing lithium; reacting the second compound with a silane compound to obtain the following formula 1: 【Chemical Formula 4】 (In Formula 1, R ０ , R ５ , and R ６ are each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, and R １ , R ２ , R ３ , and R ４ are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, and X is hydrogen (H) or a halogen), and a third step of preparing a silicon precursor compound represented by the formula:

4. The first compound is the following formula 7: [Chemical Formula 5] (In formula 7, R ０ is each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, and R ２ , R ３ and R ４ are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms), a method for preparing the silicon precursor compound according to claim 3, which is a compound represented by

5. X and R in the silicon precursor compound represented by the formula (1) １ When each is a halogen, a method for preparing the silicon precursor compound according to claim 3, including a fourth step of reacting it with a metal hydride.

6. The method for preparing a silicon precursor compound according to claim 3, wherein the silane compound is produced by reacting a chlorosilane derivative with a secondary amine.

7. A method for preparing a silicon-containing thin film, comprising the following formula 1: 【Chemical Formula 6】 (In Formula 1, R ０ , R ５ , and R ６ are each independently a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms or an isomer thereof, and R １ , R ２ , R ３ , and R ４ are each independently hydrogen (H), a halogen, or a linear or branched saturated or unsaturated hydrocarbon group having 1 to 4 carbon atoms, and X is hydrogen (H) or a halogen), a method comprising forming a silicon-containing thin film using a silicon precursor compound represented by

8. The silicon precursor compound is selected from the following compounds (1) to (36): [Chemical Formula 7] 【Chemical 8】 The method for preparing a silicon-containing thin film according to claim 7.

9. The method for preparing a silicon-containing thin film according to claim 7, wherein the silicon-containing thin film is deposited by chemical vapor deposition (CVD) or atomic layer deposition (ALD).

10. The silicon-containing thin film is any one selected from the group consisting of a silicon oxide film (SiO ２ ), a silicon oxycarbide film (SiOC), a silicon nitride film (SiN), a silicon oxynitride film (SiON), a silicon carbonitride film (SiCN), and a silicon carbide film (SiC). The method for preparing the silicon-containing thin film according to claim 7.

11. The silicon-containing thin film is a silicon oxide film (SiO ２ ), and the silicon oxide film is deposited by atomic layer deposition, The method for preparing a silicon-containing thin film according to claim 9, wherein the atomic layer deposition comprises providing a substrate in a reactor, introducing the silicon precursor compound into the reactor, purging the reactor with a purge gas, introducing an oxygen source into the reactor to react with the silicon precursor compound to form a silicon oxide film, and purging the reactor with the purge gas.

12. The method for preparing a silicon-containing thin film according to claim 11, wherein the purge gas is selected from the group consisting of nitrogen, helium, argon, and mixtures thereof.

13. The method for preparing a silicon-containing thin film according to claim 11, wherein the oxygen source is selected from the group consisting of oxygen, peroxide, oxygen plasma, water vapor, water vapor plasma, hydrogen peroxide, ozone source, and mixtures thereof.

14. The method for preparing a silicon-containing thin film according to claim 11, wherein the oxygen source contains plasma.

15. The method for preparing a silicon-containing thin film according to claim 14, wherein the plasma is generated in situ.

16. The method for preparing a silicon-containing thin film according to claim 11, wherein the atomic layer deposition is carried out at one or more temperatures of about 500 °C or lower.

17. The silicon-containing thin film is a silicon nitride film (SiN), and the silicon nitride film is deposited by plasma-enhanced atomic layer deposition. The plasma-enhanced atomic layer deposition includes providing a substrate in a reactor, introducing the silicon precursor compound into the reactor, purging the reactor with a purge gas, introducing a nitrogen-containing plasma source and an inert gas into the reactor to react with the silicon precursor compound to form a silicon nitride film, and purging the reactor with a purge gas. The method for preparing a silicon-containing thin film according to claim 9.

18. The nitrogen-containing plasma source is selected from the group consisting of nitrogen plasma, nitrogen and argon mixed plasma, ammonia plasma, nitrogen and ammonia mixed plasma, ammonia and helium mixed plasma, ammonia and argon mixed plasma, ammonia and nitrogen mixed plasma, NF ３ plasma, organic amine plasma, and mixtures thereof, a method for preparing the silicon-containing thin film according to claim 17.

19. The method for preparing a silicon-containing thin film according to claim 17, which is carried out at one or more temperatures of about 400 °C or lower.

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