Precursors for forming scandium- or yttrium-containing thin films, a method for forming scandium- or yttrium-containing thin films using the same, and a semiconductor device including the scandium- or yttrium-containing thin film

Abstract

The present invention relates to a precursor for forming a scandium- or yttrium-containing thin film, which is characterized by containing a compound represented by Chemical Formula 1, a method for forming a scandium- or yttrium-containing thin film using the same, and a semiconductor device including the scandium- or yttrium-containing thin film. By including an amidinate ligand in the precursor for thin film formation, it exhibits chemical properties of low viscosity, high volatility, high heat resistance, and high volatility, and can form a high-quality thin film.

Description

Technical Field

[0001] The present invention relates to a precursor for forming a scandium (Sc) or yttrium (Y) metal-containing thin film, a method for forming a scandium or yttrium metal-containing thin film using the same, and a semiconductor device including the scandium or yttrium-containing thin film. More specifically, the present invention relates to a precursor for forming a scandium or yttrium metal-containing thin film having low viscosity, high heat resistance, and high volatility due to a chemical structure containing an amidinate ligand, and a method for forming a high-quality thin film using the same, and a semiconductor device including the thin film.

Background Art

[0002] With the improvement of integration due to the miniaturization of the line width of semiconductor devices, the space allowed for realizing the capacitor structure is limited in terms of the line width, while the existing silicone-based dielectrics have limitations in the manufacturing method of semiconductor devices for realizing the capacitor structure. In addition, while high-k thin films are applied to replace silicone-based dielectrics, there is a problem that the leakage current due to the band gap deteriorates significantly. As one of the solutions to solve such problems, a technique for forming a high-quality thin film is required, and for this purpose, it is necessary to optimize the precursor used for thin film formation.

[0003] For this purpose, various actinide metal-containing precursors have been developed. For example, Korean Patent Publication No. 10-2019-0008427 discloses an actinide metal-containing precursor containing an aza-allyl ligand, and Korean Patent Publication No. 10-2019-0094238 discloses an actinide metal-containing precursor containing a cyclopentadienyl ligand.

[0004] In particular, in the case of a complex compound containing a cyclopentatienyl group, since it has a lower melting point and higher volatility than a compound containing β-diketonate or bis(trimethylsilyl)amide, it has an advantage in being used as a precursor in the thin film formation process.

[0005] For these reasons, in known technologies such as Korean Registered Patent Publication No. 10-1660052, Korean Published Patent Publication No. 10-2019-0109142, and No. 10-2021-0084297, a chemical structure in which cyclopentadienyl and amidinate are bonded with ligands is presented as a precursor containing actinide metals. The precursor with such ligands can improve the drawbacks of existing actinide metal precursors with low vapor pressure and high viscosity and is reported to be suitable for the thin film formation process.

[0006] Applying an amidinate ligand to a metal-containing precursor compound from such prior art is expected to improve the chemical properties of the precursor.

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present invention was devised in view of the prior art as described above, and an object thereof is to provide a novel scandium- or yttrium-containing precursor for thin film formation that can exhibit chemical properties suitable as a precursor for thin film formation.

[0008] Another object of the present invention is to provide a scandium- or yttrium-containing precursor for thin film formation that exhibits chemical properties of low viscosity, high heat resistance, and high volatility.

[0009] Another object of the present invention is to provide a method for forming a thin film using the precursor.

[0010] Another object of the present invention is to provide a semiconductor element including the thin film.

Means for Solving the Problems

[0011] The precursor for forming a scandium- or yttrium metal-containing thin film of the present invention for achieving the above object is characterized by including a compound represented by the following Chemical Formula 1. [Chemical formula] (In the formula, M is scandium (Sc) or yttrium (Y); R1 and R3 are each independently a linear, branched or cyclic alkyl or alkenyl group having 1 to 5 carbon atoms; and R2 is a hydrogen atom or a linear, branched or cyclic alkyl or alkenyl group having 1 to 6 carbon atoms.)

[0012] Further, R2 in Chemical Formula 1 may be a linear, branched or cyclic alkyl or alkenyl group having 2 to 4 carbon atoms.

[0013] Further, R1 and R3 are each independently a linear, branched or cyclic alkyl or alkenyl group having 2 to 5 carbon atoms, and R2 may be a linear, branched or cyclic alkyl or alkenyl group having 2 to 4 carbon atoms.

[0014] Further, R1 and R3 may each be a methyl group, and R2 may be an isopropyl group.

[0015] Further, R1 and R3 may be a linear alkyl or alkenyl group having 1 to 5 carbon atoms.

[0016] Further, R1 and R3 are a linear alkyl or alkenyl group having 1 to 5 carbon atoms, and R2 may be a linear alkyl or alkenyl group having 1 to 4 carbon atoms.

[0017] Further, R1 and R3 may be the same and may be an alkyl or alkenyl group.

[0018] Further, R1 to R3 may be the same and may be an alkyl or alkenyl group.

[0019] Further, the precursor for thin film formation may have the following structure.

[0020] Further, the precursor for thin film formation may have a viscosity of 60 cP or less and a melting point of 70°C or less.

[0021] Further, the precursor for thin film formation may further contain a solvent, and the solvent may be any one or more of saturated or unsaturated hydrocarbons, ketones, ethers, glymes, esters, tetrahydrofuran, and tertiary amines having C1-C 16 Moreover, the solvent may be contained in an amount of 1 to 99% by weight based on the total weight of the precursor for thin film formation.

[0022] The method for forming a scandium- or yttrium-containing thin film of the present invention includes a step of forming a thin film on a substrate using the precursor for thin film formation, and the step of forming a thin film on the substrate includes a step of depositing the precursor for thin film formation on the surface of the substrate to form a precursor thin film, and a step of reacting the precursor thin film with a reactant.

[0023] Further, the step of forming the precursor thin film may include a step of vaporizing the precursor for thin film formation and transferring it into the chamber.

[0024] Moreover, the deposition may be performed by any one of a spin-on dielectric (SOD) process, a low temperature plasma (LTP) process, a chemical vapor deposition (CVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a high density plasma-chemical vapor deposition (HDPCVD) process, an atomic layer deposition (ALD) process, or a plasma-enhanced atomic layer deposition (PEALD) process.

[0025] Also, the step of forming a thin film on the substrate may be performed in a temperature range of 150 to 500°C.

[0026] The reactant may be any one or more of nitrogen (N2), ammonia (NH3), hydrazine (N2H4), nitrous oxide (N2O), oxygen (O2), water vapor (H2O), ozone (O3), hydrogen peroxide (H2O2), silane, hydrogen (H), and diborane (B2H6).

[0027] Also, the step of forming a scandium- or yttrium-containing thin film on the substrate may include supplying the thin film-forming precursor to the substrate and applying plasma to form a thin film.

[0028] Also, the scandium- or yttrium-containing thin film of the present invention can be formed using the thin film-forming precursor, and the semiconductor device of the present invention is characterized by including a thin film manufactured by the method for forming a scandium- or yttrium-metal-containing thin film.

Advantages of the Invention

[0029] The precursor for forming a scandium- or yttrium-containing thin film according to the present invention contains an amidinate ligand, so it has excellent structural stability of the precursor compound and exhibits characteristics of low viscosity, high volatility, and high heat resistance. Therefore, it shows physical properties suitable for use in the step of forming a scandium- or yttrium-containing thin film.

[0030] Also, a high-quality scandium- or yttrium-containing thin film can be formed using the precursor, and a semiconductor device including a scandium- or yttrium-containing thin film manufactured by the thin film-forming method can be provided.

Brief Description of the Drawings

[0031]

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Figure 19

Mode for Carrying Out the Invention

[0032] Hereinafter, the present invention will be described in more detail. Terms and words used in this specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and in accordance with the principle that the inventor can appropriately define the concept of the terms in order to explain his invention in the best way, they should be construed in a meaning and concept that conforms to the technical idea of the present invention.

[0033] The precursor for forming a scandium- or yttrium-containing thin film according to the present invention is characterized by containing a compound represented by the following Chemical Formula 1.

Chemical Formula

[0034] In the amidinate ligand, R1 and R3 may be the same or different, but it can be seen that it is preferable in terms of heat resistance and viscosity to include a ligand having the same symmetric structure for R1 and R3.

[0035] Also, in Chemical Formula 1, R2 constituting the amidinate ligand may be a hydrogen atom, or a linear, branched or cyclic alkyl group or alkenyl group having 1 to 4 carbon atoms, but preferably may include an n-alkyl group such as an ethyl group, a propyl group, or a butyl group.

[0036] The precursor for thin film formation can form compounds in various forms depending on the type of functional group.

[0037] In one embodiment, R2 in Chemical Formula 1 may be a linear, branched or cyclic alkyl group or alkenyl group having 2 to 4 carbon atoms.

[0038] Also, R1 and R3 are each independently a linear, branched or cyclic alkyl group or alkenyl group having 2 to 5 carbon atoms, and R2 may be a linear, branched or cyclic alkyl group or alkenyl group having 2 to 4 carbon atoms.

[0039] Also, R1 and R3 may be a methyl group, and R2 may be an isopropyl group.

[0040] Also, R1 and R3 may be a linear alkyl group or alkenyl group having 1 to 5 carbon atoms.

[0041] Also, R1 and R3 are a linear alkyl group or alkenyl group having 1 to 5 carbon atoms, and R2 may be a linear alkyl group or alkenyl group having 1 to 4 carbon atoms.

[0042] Also, R1 and R3 may both be the same and may be an alkyl group or an alkenyl group.

[0043] Also, both R1 and R3 may be the same and may be an alkyl group or an alkenyl group.

[0044] Further, the precursor for thin film formation can have the following structure.

[0045] The precursor for thin film formation as described above can exemplify the following chemical structure.

Chemical formula

[0046] The compound represented by the above Chemical formula 1 is a precursor containing an amidinate ligand with scandium or yttrium as the central metal atom. Since it has a low viscosity, high thermal stability and high volatility, and can have a liquid form at room temperature, the chemical characteristics of the target precursor can be obtained by synthesizing the precursor containing the ligand.

[0047] Specifically, the precursor for thin film formation may have a viscosity of 60 cP or less and a melting point of 70°C or less.

[0048] Such a chemical structure of the precursor for thin film formation can obtain a liquid precursor with low viscosity, high heat resistance and high volatility, and thereby a high-quality thin film can be formed.

[0049] Further, the precursor for thin film formation of the present invention can further contain a solvent for dissolving or diluting the precursor compound in consideration of the conditions and efficiency of the thin film formation process. As the solvent, any one of saturated or unsaturated hydrocarbons, ketones, ethers, glymes, esters, tetrahydrofuran, and tertiary amines having C1-C 16 or a mixture thereof can be used. Examples of the saturated or unsaturated hydrocarbons having C1-C 16 include toluene, heptane, etc., and examples of the tertiary amine include dimethylethylamine.

[0050] In particular, depending on the chemical structure, the compound of the precursor for thin film formation can be in a solid state at room temperature. In this case, by including the solvent, the compound can be dissolved. That is, when the solvent is included, it is preferably contained in a solvent and content that can dissolve the precursor compound, and is contained in an amount of 1 to 99% by weight based on the total weight of the precursor for thin film formation.

[0051] Whether or not the precursor contains the solvent can be vaporized, so it can be supplied into the chamber in the form of a precursor gas. Therefore, when the precursor compound for thin film formation exists in a liquid state at room temperature and can be easily vaporized depending on the type, the thin film formation process can be carried out without a separate solvent.

[0052] In addition, the scandium or yttrium-containing thin film formation process can be carried out by any one of a spin-on dielectric (SOD) process, a low temperature plasma (LTP) process, a chemical vapor deposition (CVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a high density plasma-chemical vapor deposition (HDPCVD) process, an atomic layer deposition (ALD) process, or a plasma-enhanced atomic layer deposition (PEALD) process.

[0053] For example, when applying the HDP-CVD process, it can be carried out at high vacuum and high power compared to an atmospheric pressure chemical vapor deposition (AP-CVD) process, a low pressure chemical vapor deposition (LP-CVD) process, or a plasma enhanced chemical vapor deposition (PE-CVD) process. Therefore, a thin film with a structurally dense and excellent mechanical property can be formed.

[0054] Therefore, the thin film forming method according to the present invention includes a step of forming a thin film on a substrate using the thin film forming precursor.

[0055] Specifically, the step of forming a scandium- or yttrium-containing thin film on the substrate may include a step of depositing the thin film forming precursor on the surface of the substrate to form a precursor thin film, and a step of reacting the precursor thin film with a reactant.

[0056] Further, it may include a step of vaporizing the thin film forming precursor for deposition of the precursor and transferring it into the chamber.

[0057] Also, the step of forming a scandium- or yttrium-containing thin film on the substrate may include a step of supplying the thin film forming precursor to the substrate and applying plasma in the presence of a reactant to form a thin film such as a metal, oxide, nitride, or oxynitride.

[0058] The step of forming the thin film can be performed under a pressure condition in the chamber of 1 to 1000 mTorr. Also, the source power for forming plasma in the chamber is appropriately 500 to 9,000 W, and the bias power is 0 to 5,000 W. Also, the bias power may not be applied in some cases.

[0059] Also, the step of forming a thin film on the substrate can be performed in a temperature range of 150 to 500°C.

[0060] Also, when supplying the precursor for thin film formation, in order to further improve the electrical characteristics of the finally formed metal film, that is, the capacitance or leakage current value, a second metal precursor can be introduced as necessary. The second metal precursor can be selectively further supplied with a metal precursor containing one or more metals (M) selected from silicon (Si), titanium (Ti), germanium (Ge), strontium (Sr), niobium (Nb), barium (Ba), hafnium (Hf), tantalum (Ta), and actinium group (Ac) atoms. The second metal precursor can be an alkylamide-based compound or an alkoxy-based compound containing the metal. As an example, when the metal is Si, SiH(N(CH3)2)3, Si(N(C2H5)2)4, Si(N(C2H5)(CH3))4, Si(N(CH3)2)4, Si(OC4H9)4, Si(OC2H5)4, Si(OCH3)4, Si(OC(CH3)3)4, etc. can be used.

[0061] The supply of the second metal precursor can be performed in the same manner as the supply method of the precursor for thin film formation. The second metal precursor may be supplied onto the thin film formation substrate together with the precursor, or may be sequentially supplied after the supply of the precursor is completed.

[0062] The precursor for thin film formation and optionally the second metal precursor as described above are preferably maintained at a temperature of 50 to 250 °C, more preferably 100 to 200 °C, until they are supplied into the reaction chamber in order to contact the thin film formation substrate.

[0063] Also, prior to the supply of the reactant after the precursor supply step, in order to assist the movement of the precursor and optionally the second metal precursor onto the substrate, or to make the pressure in the reactor appropriate for vapor deposition, and to release impurities present in the chamber to the outside, a step of purging the reactor with an inert gas such as argon (Ar), nitrogen (N2), or helium (He) can be performed. At this time, the purging of the inert gas is preferably performed so that the pressure in the reactor becomes 1 to 5 Torr.

[0064] In addition, as the reactant, any one or more of nitrogen (N2), ammonia (NH3), hydrazine (N2H4), nitrous oxide (N2O), oxygen (O2), water vapor (H2O), ozone (O3), hydrogen peroxide (H2O2), silane, hydrogen (H), and diborane (B2H6) can be used. When carried out in the presence of oxidizing gases such as water vapor, oxygen, and ozone, a magnesium oxide thin film can be formed. When carried out in the presence of reducing gases such as hydrogen, ammonia, hydrazine, and silane, a thin film of a simple metal or a metal nitride can be formed. Also, a metal oxynitride thin film can be formed by mixing reactants.

[0065] In addition to plasma treatment, a treatment step by heat treatment or light irradiation can also be carried out. It is for providing thermal energy for the deposition of the thin film-forming precursor and can be carried out by a normal method. Preferably, in order to produce a thin film having a desired physical state and composition at a sufficient growth rate, the treatment step is preferably carried out so that the temperature of the substrate in the reactor is 100 to 1,000 °C, preferably 250 to 400 °C.

[0066] Also, during the treatment step, as described above, to assist the movement of the reactants onto the substrate, or to make the pressure in the reactor appropriate for deposition, and to release impurities or by-products present in the reactor to the outside, a step of purging the reactor with an inert gas such as argon (Ar), nitrogen (N2), or helium (He) can be carried out.

[0067] By repeating the above-described treatment steps of introducing the thin film-forming precursor, introducing the reactant, and introducing the inert gas one cycle at a time for one cycle or more, a thin film can be formed.

[0068] In addition, when the thin film forming step is applied, various semiconductor devices including the thin film can be manufactured.

[0069] [Synthesis Example 1] Synthesis of Tris-(diethyl-n-propylamidinate)yttrium [Y(Et2nPr-AMD)3] 65.57 g (0.4609 mol) of di-n-propyl-ethylamidinate was charged into 300 ml of THF, and after cooling to -78°C, 184.4 ml (0.4609 mol) of an n-BuLi hexane solution (2.5 M) was slowly added dropwise to produce Li-(Et2nPr-AMD). The solution was stirred at -78°C for 30 minutes, then warmed to room temperature and further stirred at room temperature for 2 hours. The produced Li-(Et2nPr-AMD) solution was slowly added dropwise to a flask containing 30 g (0.4609 mol) of YCl3 at -78°C, and stirred at room temperature for 6 hours. The mixture was evaporated under vacuum, dissolved in 200 ml of pentane, filtered, and the solvent and volatile substances were evaporated under vacuum. The resulting yellow liquid was distilled at 156°C and 30.1 mTorr to obtain a pale yellow liquid. The yield was 61.10 g (77.6%). The NMR (AV400 MHz HD manufactured by Bruker) analysis results are as shown in Figure 1, and the characteristic peaks are attributed as follows. 1 1H NMR (C6D6, 25°C): 0.087 (t, 3H), 1.32 (t, 6H), 1.52 (q, 2H), 2.21 (q, 2H), 3.24 (q, 4H)

[0070] The pale yellow liquid was 0.1% during TGA (SDT Q600 manufactured by TA Instruments) analysis measured at a heating rate of 10°C / min in an atmosphere where nitrogen was flowing at 200 ml / min, and almost no residual mass remained. Such results are shown in Figure 2, which is the TGA analysis result showing the percentage of weight loss due to temperature change.

[0071] After putting the yellow liquid sample into a sealed container for DSC and maintaining it at 40°C for 10 minutes, a decomposition peak was observed at 410°C during DSC (Discovery 25 manufactured by TA Instruments) analysis measured at a temperature increase rate of 10°C / min. Such results are shown in Figure 3, which is the DSC analysis result showing the change in thermal energy due to temperature change.

[0072] [Synthesis Example 2] Synthesis of Tris-(diethyl-ethylamidinato)yttrium [Y(Et2Et-AMD)3] 59.10 g (0.4609 mol) of diethyl-ethylamidinato was added to 300 ml of THF, and after cooling to -78 °C, 184.4 ml (0.4609 mol) of an n-BuLi hexane solution (2.5 M) was slowly added dropwise to produce Li-(Et2Et-AMD). The solution was stirred at -78 °C for 30 minutes, then warmed to room temperature and further stirred at room temperature for 2 hours. The produced Li-(Et2Et-AMD) solution was slowly added dropwise to a flask containing 30 g (0.4609 mol) of YCl3 at -78 °C, and the mixture was stirred at room temperature for 6 hours. The mixture was evaporated under vacuum, dissolved in 200 ml of pentane, filtered, and the solvent and volatile substances were evaporated under vacuum. The resulting yellow liquid was distilled at 160 °C and 30 mTorr to obtain a pale yellow solid. The yield was 52.4 g (72.5%). The NMR (AV400 MHz HD manufactured by Bruker) analysis results were as shown in Figure 4, and the characteristic peaks were assigned as follows. 1 1H NMR (C6D6, 25 °C): 0.98 (t, 3H), 1.29 (t, 6H), 2.14 (q, 2H), 3.20 (q, 4H)

[0073] During TGA (SDT Q600 manufactured by TA Instruments) analysis measured at a temperature increase rate of 10 °C / min in an atmosphere where nitrogen was flowing at 200 ml / min, the pale yellow solid was 1.4%, leaving almost no residual mass. Such results are shown in Figure 5, which is the TGA analysis result showing the percentage of weight loss due to temperature change.

[0074] [Synthesis Example 3] Synthesis of Tris-(di-n-propyl-ethylamidinato)yttrium [Y(nPr2Et-AMD)3] 71.01 g (0.4609 mol) of di-n-propyl-ethylamidinato was added to 300 ml of THF, and after cooling to -78 °C, 184.4 ml (0.4609 mol) of an n-BuLi hexane solution (2.5 M) was slowly added dropwise to produce Li-(nPr2Et-AMD). The solution was stirred at -78 °C for 30 minutes, then warmed to room temperature and further stirred at room temperature for 2 hours. The produced Li-(nPr2Et-AMD) solution was slowly added dropwise to a flask containing 30 g (0.4609 mol) of YCl3 at -78 °C, and stirred at room temperature for 6 hours. The mixture was evaporated under vacuum, dissolved in 200 ml of pentane, filtered, and the solvent and volatile substances were evaporated under vacuum. The resulting yellow liquid was distilled at 221 °C and 42.6 mTorr to obtain a pale yellow solid. The yield was 55.30 g (64.9%). The NMR (AV400 MHz HD manufactured by Bruker) analysis results were as shown in Figure 6, and the characteristic peaks were assigned as follows. 1 H NMR (C6D6, 25 °C): 1.02 (t, 9H), 1.71 (q, 4H), 2.22 (q, 2H), 3.18 (q, 4H)

[0075] The pale yellow solid was 0.75% during TGA (SDT Q600 manufactured by TA Instruments) analysis measured at a temperature increase rate of 10 °C / min in an atmosphere where nitrogen was flowing at 200 ml / min, leaving almost no residual mass. Such results are shown in Figure 7, which is the TGA analysis result showing the percentage of weight loss due to temperature change.

[0076] [Synthesis Example 4] Synthesis of Tris-(diethyl-n-butylamidinato)yttrium [Y(Et2nBu-AMD)3] 120.05 g (0.7682 mol) of diethyl-n-butylamidinato was added to 300 ml of THF, and after cooling to -78 °C, 307.3 ml (0.7682 mol) of an n-BuLi hexane solution (2.5 M) was slowly added dropwise to produce Li-(Et2nBu-AMD). The solution was stirred at -78 °C for 30 minutes, then warmed to room temperature and further stirred at room temperature for 2 hours. The produced Li-(Et2nBu-AMD) solution was slowly added dropwise to a flask containing 30 g (0.2561 mol) of YCl3 at -78 °C, and stirred at room temperature for 6 hours. The mixture was evaporated under vacuum, dissolved in 200 ml of pentane, filtered, and the solvent and volatiles were evaporated under vacuum. The resulting orange liquid was distilled at 210 °C and 141 mTorr to obtain a pale yellow liquid. The yield was 116.0 g (81.7%). The NMR (AV400 MHz HD manufactured by Bruker) analysis results are as shown in Figure 8, and the characteristic peaks were assigned as follows. 1 H NMR (C6D6, 25 °C): 0.850 (t, 3H), 1.28 (q, 2H), 1.35 (t, 6H), 1.50 (m, 2H), 2.25 (m, 2H), 3.29 (q, 4H)

[0077] The pale yellow solid was 1.67% during TGA (SDT Q600 manufactured by TA Instruments) analysis measured at a temperature increase rate of 10 °C / min in an atmosphere where nitrogen was flowing at 200 ml / min, leaving almost no residual mass. Such results are shown in Figure 9, which shows the TGA analysis results indicating the percentage of weight loss due to temperature change.

[0078] [Synthesis Example 5] Synthesis of Tris-(diethyl-n-propylamidinato)scandium [Sc(Et2nPr-AMD)3] 300 ml of THF was charged with 58.79 g (0.3965 mol) of di-n-propyl-ethylamidinato, cooled to -78 °C, and then 158.61 ml (0.3965 mol) of an n-BuLi hexane solution (2.5 M) was slowly added dropwise to produce Li-(Et2nPr-AMD). The solution was stirred at -78 °C for 30 minutes, then warmed to room temperature and further stirred at room temperature for 2 hours. The produced Li-(Et2nPr-AMD) solution was slowly added dropwise to a flask containing 20 g (0.396 mol) of ScCl3 at -78 °C and stirred at room temperature for 6 hours. The mixture was evaporated under vacuum, dissolved in 150 ml of pentane, filtered, and the solvent and volatile substances were evaporated under vacuum. The resulting yellow liquid was distilled at 185 °C and 18.0 mTorr to obtain a pale yellow liquid. The yield was 56.80 g (78.6%). The NMR (AV400 MHz HD manufactured by Bruker) analysis results were as shown in Figure 10, and the characteristic peaks were assigned as follows. 1 H NMR (C6D6, 25 °C): 0.088 (t, 3H), 1.30 (t, 6H), 1.51 (q, 2H), 2.18 (q, 2H), 3.26 (q, 4H)

[0079] The pale yellow liquid was 0.19% during TGA (SDT Q600 manufactured by TA Instruments) analysis measured at a temperature increase rate of 10 °C / min in an atmosphere where nitrogen was flowing at 200 ml / min, leaving almost no residual mass. Such results are shown in Figure 11, which is the TGA analysis result showing the percentage of weight loss due to temperature change.

[0080] After placing the pale yellow liquid sample in a sealed container for DSC and maintaining it at 40 °C for 10 minutes, a decomposition peak was observed at 450 °C during DSC (Discovery25 manufactured by TA Instruments) analysis measured at a temperature increase rate of 10 °C / min. Such results are shown in Figure 12, which is the DSC analysis result showing the change in thermal energy due to temperature change.

[0081] [Synthesis Example 6] Synthesis of Tris-(diethyl-ethylamidinato)scandium [Sc(Et2Et-AMD)3] 50.84 g (0.3965 mol) of diethyl-ethylamidin ate was added to 300 ml of THF, and after cooling to -78 °C, 158.6 ml (0.3965 mol) of an n-BuLi hexane solution (2.5 M) was slowly added dropwise to produce Li-(Et2Et-AMD). After stirring the solution at -78 °C for 30 minutes, it was warmed to room temperature and further stirred at room temperature for 2 hours. The produced Li-(Et2Et-AMD) solution was slowly added dropwise to a flask containing 20 g (0.3965 mol) of ScCl3 at -78 °C, and stirred at room temperature for 6 hours. The mixture was evaporated under vacuum, dissolved in 150 ml of pentane, filtered, and the solvent and volatile substances were evaporated under vacuum. The resulting yellow liquid was distilled at 145 °C and 28.3 mTorr to obtain a pale yellow solid. The yield was 41.8 g (74.1%). The NMR (AV400 MHz HD manufactured by Bruker) analysis results are as shown in Figure 13, and the characteristic peaks were assigned as follows. 1 1H NMR (C6D6, 25 °C): 0.99 (t, 3H), 1.28 (t, 6H), 2.15 (q, 2H), 3.20 (q, 4H)

[0082] The pale yellow solid was 0.3% during TGA (SDT Q600 manufactured by TA Instruments) analysis measured at a heating rate of 10 °C / min in an atmosphere where nitrogen was flowing at 200 ml / min, leaving almost no residual mass. Such results are shown in Figure 14, which is the TGA analysis result showing the percentage of weight loss due to temperature change.

[0083] Among the precursors according to Synthesis Examples 1 to 6, the measured TGA analysis results are shown in Table 1.

Table 1

[0084] Among the precursors obtained by Synthesis Examples 1, 3, and 5, the measured DSC analysis results are shown in Table 2.

Table 2

[0085] To confirm the viscosities of the precursors of Synthesis Example 1 and Synthesis Example 5, samples were placed in the measuring container of a rotational viscometer (LVD2T manufactured by Brookfield), and the viscosities were measured using a spindle for low viscosities under the condition of 25°C. The results are shown in Table 3. [Table 3]

[0086] The following thin film formation process was performed using the precursor.

[0087] Using the precursor of Synthesis Example 1 and O3 as an oxidizing agent, film formation evaluation by an atomic layer deposition process was performed in a bubbler method. The film formation evaluation was based on the change in the thin film thickness according to the process cycle (Number of cycles vs. Thickness).

[0088] After heating the precursor of Synthesis Example 1 to the vaporization temperature, argon (Ar) gas was injected through a Dip line to generate bubbles, and thus the vapor of the precursor compound in the gaseous state was supplied into the reaction chamber through a carrier gas.

[0089] SiO2 substrates and TiN substrates were provided in the reaction chamber, and in order to confirm the change in the thin film thickness according to the process cycle while maintaining the set temperature (300°C), vapor deposition evaluation was performed under the conditions of precursor (60 seconds) - purge (80 seconds) - oxidizing agent (15 seconds) - purge (20 seconds).

[0090] The purge process was performed at a flow rate of 700 sccm of argon (Ar) gas, and ozone (O3) as the reaction gas was injected at a concentration of 220 g / m 3 . The precursor was heated to 80°C and flowed at an argon carrier gas injection amount of 200 sccm, and the number of process cycles was set to 50, 100, and 150 cycles. The results of the change in the thin film thickness according to the number of vapor deposition cycles in the 300°C process are shown in Fig. 15.

[0091] Looking at the results in Fig. 15, it can be confirmed that for the evaluated SiO2 and TiN specimens, there is a constant change in the thin film thickness with the number of deposition cycles under the process temperature conditions.

[0092] Also, the deposition rates for different substrates at 300 °C are as shown in Table 4.

Table 4

[0093] In addition, in order to measure the change in the deposition rate (ALD window) at a process temperature of 300 °C, after heating the precursor according to Synthesis Example 3 to the vaporization temperature, argon (Ar) gas was injected through the Dip line to generate bubbles, so that the vapor of the precursor compound in the gaseous state was supplied into the reaction chamber through the carrier gas.

[0094] SiO2 and TiN substrates were placed in the reaction chamber, and in order to confirm the change in the thin film deposition rate with the process temperature while changing the temperature, the precursor (60 seconds) - purge (80 seconds) - oxidant (15 seconds) - purge (20 seconds) were supplied in this order. The purge process was carried out at a flow rate of 700 sccm using argon (Ar) gas. Ozone (O3), which is the reaction gas, was injected at a concentration of 220 g / m 3 The precursor was heated to 80 °C and flowed at an argon carrier gas injection rate of 200 sccm. The number of process cycles was 50 cycles. The results regarding the change in the thin film deposition rate with the process temperature are shown in Fig. 16.

[0095] Looking at the results in Fig. 16, similar thin film deposition rates (nm / cycle) are shown at process temperatures of 275 °C and 300 °C, from which it can be seen that there is a process temperature range (ALD window).

[0096] In addition, in order to confirm the film crystallinity for each process temperature, XRD analysis was performed on the Y2O3 thin films obtained for each process temperature through the above process evaluation using SiO2 and TiN specimens, thereby confirming the crystallinity of the thin films. The crystallinity was measured after the deposition process, and analysis was also performed on the specimens after heat treatment at 600 °C for 30 seconds under N2 conditions using RTA. As a result of the analysis, cubic form Y2O3 crystallinity was confirmed in the thin film deposited under the condition of 300 °C in the as-deposited thin film. After the heat treatment, it was confirmed that more cubic form Y2O3 crystallinity was generated. The analyzed XRD results are shown in Fig. 17.

[0097] In addition, in order to confirm the composition and impurities of the thin film, XPS depth profile analysis was performed. The composition and impurity content of the thin film were confirmed by XPS analysis on the Y2O3 thin film deposited on SiO2 and TiN specimens at 300 °C. It was confirmed that the C and N impurities in the thin film were both 0%. It was confirmed that the content ratio of O / Y had a composition ratio of O / Y = 1.19 on the SiO2 substrate and O / Y = 1.26 on the TiN substrate. The analyzed XPS depth profile results are shown in Fig. 18.

[0098] In addition, in order to confirm the electrical properties of the thin film, after depositing TiN as the upper electrode on the deposited thin film, the dielectric constant and current density were measured. The results are as shown in Table 5 and Fig. 19.

Table 5

[0099] From such results, it was confirmed that high-quality scandium or yttrium-containing thin films can be formed using the precursor for thin film formation of the present invention.

[0100] Although the present invention has been described by way of preferred embodiments as described above, it is not limited to the above embodiments, and various modifications and changes can be made by those having ordinary knowledge in the technical field to which the invention pertains without departing from the spirit of the present invention. Those modified examples and changed examples should also be regarded as belonging to the scope of the present invention and the appended claims.

Claims

1. A precursor for forming a scandium- or yttrium-containing thin film, characterized by containing a scandium- or yttrium-containing compound represented by the following Chemical Formula 1. 【Chemical 1】 (wherein, M is scandium or yttrium metal, and R １ and R ３ are each independently a linear, branched or cyclic alkyl or alkenyl group of C １ -C ５ , and R ２ is a hydrogen atom or a linear, branched or cyclic alkyl or alkenyl group of C １ -C ６ .)

2. The R in the chemical formula 1 ２ is ２ -C ４ a linear, branched or cyclic alkyl group or alkenyl group, and the precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that.

3. The R in the chemical formula 1 １ and R ３ are each independently a linear, branched or cyclic alkyl group or alkenyl group of C ２ -C ５ , and the R ２ is a linear, branched or cyclic alkyl group or alkenyl group of C ２ -C ４ The precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that it is a linear, branched or cyclic alkyl group or alkenyl group of

4. The R in the chemical formula 1 １ and R ３ are methyl groups, and the precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that.

5. The R in the chemical formula 1 ２ is an isopropyl group, and the precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that.

6. The R in the chemical formula 1 １ and R ３ are each independently a linear alkyl group or alkenyl group of C １ -C ５ The precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that it is such.

7. In the formula (1), the R １ and R ３ are a linear alkyl group or alkenyl group of C １ -C ５ , and the R ２ is a linear alkyl group or alkenyl group of C １ -C ４ The precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that it is

8. The R in the chemical formula 1 １ and R ３ are both the same and are a linear, branched or cyclic alkyl group or alkenyl group of C １ -C ５ The precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that it is such.

9. The R in the chemical formula 1 １ ~R ３ are all the same and are a linear, branched or cyclic alkyl group or alkenyl group of C １ -C ５ The precursor for forming a scandium- or yttrium-containing thin film according to claim 1, characterized in that it is such.

10. The precursor for forming a scandium- or yttrium-containing thin film according to Claim 1, wherein the viscosity is 60 cP or less.

11. The precursor for forming a scandium- or yttrium-containing thin film according to Claim 1, wherein the melting point is 70°C or less.

12. The precursor for forming a scandium- or yttrium-containing thin film according to Claim 1, wherein the precursor for forming the thin film further contains a solvent.

13. The solvent is C １ -C １６ The precursor for forming a scandium- or yttrium-containing thin film according to claim 12, characterized in that the solvent is any one or more of saturated or unsaturated hydrocarbons, ketones, ethers, glymes, esters, tetrahydrofuran, and tertiary amines.

14. The precursor for forming a scandium- or yttrium-containing thin film according to Claim 12, wherein the solvent is contained in an amount of 1 to 99% by weight based on the total weight of the precursor for forming the thin film.

15. The precursor for forming a thin film according to Claim 1, wherein the scandium- or yttrium-containing compound represented by Chemical Formula 1 is at least one selected from the group consisting of the following structures. 【Chemical Formula 2】

16. A method for forming a scandium- or yttrium-containing thin film, characterized by including a step of forming a thin film on a substrate using the precursor for forming a thin film according to Claim 1 or 12.

17. The step of forming a thin film on the substrate is a step of depositing the precursor for forming the thin film on the surface of the substrate to form a precursor thin film, and a step of reacting the precursor thin film with a reactive gas, and is characterized by including the above steps, and is the method for forming a scandium- or yttrium-containing thin film according to Claim 16.

18. The method for forming a scandium- or yttrium-containing thin film according to Claim 17, wherein the step of forming the precursor thin film includes a step of vaporizing the precursor for forming the thin film and transferring it into the chamber.

19. The vapor deposition is performed by any one of a spin-on dielectric (SOD) process, a low temperature plasma (LTP) process, a chemical vapor deposition (CVD), a plasma enhanced chemical vapor deposition (PECVD), a high density plasma-chemical vapor deposition (HDP-CVD) process, an atomic layer deposition (ALD) process, or a plasma-enhanced atomic layer deposition (PEALD) process. The method for forming a scandium- or yttrium-containing thin film according to claim 17, characterized in that it is performed by any one of the above processes.

20. The step of forming a thin film on the substrate is characterized by including a step of supplying the precursor for thin film formation to the substrate and applying plasma to form a thin film. The method for forming a scandium- or yttrium-containing thin film according to claim 16.

21. A semiconductor device, characterized by including a scandium- or yttrium-containing thin film manufactured by the thin film forming method according to claim 16.

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