Method of depositing thin films and method of manufacturing a memory device

Abstract

The method for depositing a thin film includes: supplying a precursor into a cavity to be adsorbed onto a substrate; purifying the inside of the cavity; and supplying a reactant into the cavity to react with the precursor to form a thin film and fill the gap portion, the precursor being formed by mixing 1-5 moles of a compound represented by Chemical Formula 1 or Chemical Formula 2 and 1-5 moles of a metal compound, <Chemical Formula 1> wherein X is O or S, and R1 or R2 is each independently selected from an alkyl group having 1-8 carbon atoms, a cycloalkyl group having 3-6 carbon atoms, and an aryl group having 6-12 carbon atoms, <Chemical Formula 2> wherein X is O or S, n is 1-5, and R1-R4 is each independently selected from a hydrogen atom, an alkyl group having 1-5 carbon atoms, a cycloalkyl group having 3-6 carbon atoms, and an aryl group having 6-12 carbon atoms.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method of depositing a thin film and a method of manufacturing a storage device, and more particularly, to a method of depositing a thin film using an adduct precursor and a method of manufacturing a storage device including the method of depositing a thin film. BACKGROUND

[0002] As a process of filling a gap portion such as a trench formed on a substrate, atomic layer deposition (ALD) is used. Since atomic layer deposition uses a surface reaction, when a gap portion is filled using atomic layer deposition, a uniform thickness can be formed, thereby minimizing the formation of voids.

[0003] However, as the gap portion becomes high aspect ratio, a case in which the size of the gap entrance is smaller than the inner size of the gap occurs. Also, when the gap entrance is narrow, the reactants are hindered from sufficiently diffusing to the lower portion of the high aspect ratio feature.

[0004] Insufficient diffusion also causes a deposition profile in which the coverage of the sidewall decreases as the depth increases, and even though atomic layer deposition is used, defects such as voids or seams occur, resulting in a film having a larger porosity than desired.

[0005] In addition, ALD for filling a gap can require several hundreds of repetitions to achieve a target film thickness, which is not good for throughput. Therefore, in the case of a gap portion having a high aspect ratio, it is advantageous to have a higher growth rate in the lower portion than in the upper portion, and for this reason, various growth inhibition techniques have been developed. SUMMARY

[0006] An object of the present invention is to provide a method of depositing a thin film that can minimize the occurrence of defects and ensure a high yield, and a method of manufacturing a storage device including the method of depositing a thin film.

[0007] Other objects of the present invention will become more apparent in light of the following detailed description.

[0008] A method of depositing a thin film according to the present invention includes the steps of supplying an adduct precursor into a cavity in which a substrate including at least one gap portion is disposed, so that the adduct precursor is adsorbed onto the substrate; purifying the inside of the cavity; and supplying a reaction material into the inside of the cavity, so that the reaction material reacts with the adduct precursor to form a thin film and fill the gap portion, wherein the adduct precursor is formed by mixing 1 to 5 moles of a compound represented by Chemical Formula 1 or Chemical Formula 2 below and 1 to 5 moles of a metal compound.

[0009] <Chemical Formula 1>

[0010]

[0011] wherein X is O or S, and R1or R2is each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0012] <Chemical Formula 2>

[0013]

[0014] wherein X is O or S, n is 1 to 5, and R1to R4are each independently selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0015] The adduct precursor can be formed by mixing the metal compound with ethyl methyl sulfide, ethyl propyl ether, or tetrahydrofuran.

[0016] The metal compound can include at least one of Zr, Hf, and Ti, which are group 4 elements, as a central element.

[0017] The metal compound can be represented by the following Chemical Formula 3.

[0018] <Chemical Formula 3>

[0019]

[0020] wherein M is selected from a metal element belonging to group 4 of the periodic table,

[0021] Each L is the same or different from each other, and is selected from a hydrogen atom, a straight chain / branched chain / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0022] The metal compound can be represented by the following Chemical Formula 4.

[0023] <Chemical Formula 4>

[0024]

[0025] wherein M is selected from a metal element belonging to group 4 of the periodic table,

[0026] R1, R2, R3, R4, and R5are each independently selected from a hydrogen atom, a straight chain / branched chain / cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a phenyl group having 6 to 12 carbon atoms.

[0027] Each L is the same or different, and is selected from a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element,

[0028] When L is a dialkylamino group, the dialkylamino groups are connected to each other to form a cyclic amino group having 3 to 10 carbon atoms.

[0029] The metal compound can include at least one of Group 5 elements of Nb and Ta as a central element.

[0030] The metal compound can be represented by the following Chemical Formula 5 or the following Chemical Formula 6.

[0031] <Chemical Formula 5>

[0032]

[0033] <Chemical Formula 6>

[0034]

[0035] wherein M is selected from metal elements belonging to Group 5 of the periodic table,

[0036] Each L is the same or different, and is selected from a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0037] The metal compound can be represented by the following Chemical Formula 7.

[0038] <Chemical Formula 7>

[0039]

[0040] wherein M is selected from metal elements belonging to Group 5 of the periodic table,

[0041] R1, R2, and R3 are each independently selected from a hydrogen atom and a linear / branched / cyclic alkyl group having 1 to 5 carbon atoms,

[0042] each L is the same or different, and is selected from the group consisting of a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0043] The metal compound can include at least one of Group 6 elements of W and Mo as a central element.

[0044] The metal compound can be represented by the following Chemical Formula 8 or the following Chemical Formula 9.

[0045] <Chemical Formula 8>

[0046]

[0047] <Chemical Formula 9>

[0048]

[0049] wherein M is selected from metal elements belonging to Group 6 of the periodic table,

[0050] each L is the same or different, and is selected from the group consisting of a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0051] The metal compound can include at least one of Group 13 elements of Al as a central element.

[0052] The metal compound can be represented by the following Chemical Formula 10.

[0053] <Chemical Formula 10>

[0054]

[0055] wherein M is selected from metal elements belonging to Group 13 of the periodic table,

[0056] each L is the same or different, and is selected from the group consisting of a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0057] A method of depositing a thin film includes the steps of supplying an adduct precursor to the inside of a chamber in which a substrate including at least one gap portion is disposed, thereby the adduct precursor is adsorbed onto the substrate; purifying the inside of the chamber; and supplying a reaction material to the inside of the chamber, thereby the reaction material reacts with the adduct precursor to form a thin film and fill the gap portion, wherein the adduct precursor is formed by mixing 1 to 5 moles of a compound represented by Chemical Formula 1 or Chemical Formula 2 below with 1 to 5 moles of a non-metal compound.

[0058] <Chemical Formula 1>

[0059]

[0060] wherein X is O or S, and R1 or R2 is each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0061] <Chemical Formula 2>

[0062]

[0063] wherein X is O or S, n is 1 to 5, and R1 to R4 is each independently selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0064] The adduct precursor is formed by mixing the metal compound with ethyl methyl sulfide, ethyl propyl ether, or tetrahydrofuran.

[0065] The non-metal compound can include at least one of Group 14 elements including Si and Ge as a central element.

[0066] The non-metal compound is represented by Chemical Formula 11 below.

[0067] <Chemical Formula 11>

[0068]

[0069] wherein M is one of Group 14 elements including Si and Ge.

[0070] R1to R4are each selected independently from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 1 to 10 carbon atoms, an arylamino group having 6 to 12 carbon atoms, an aralkylamino group having 7 to 13 carbon atoms, a cyclic amino group having 3 to 10 carbon atoms, a heterocyclic amino group having 3 to 10 carbon atoms, a heteroaryl amino group having 6 to 12 carbon atoms, an alkylsilylamino group having 2 to 10 carbon atoms, an azido group, and a halogen.

[0071] The non-metal compound is represented by the following Chemical Formula 12.

[0072] <Chemical Formula 12>

[0073]

[0074] wherein M is one of Group 14 elements including Si and Ge,

[0075] R1to R6are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 1 to 10 carbon atoms, an arylamino group having 6 to 12 carbon atoms, an aralkylamino group having 7 to 13 carbon atoms, a cyclic amino group having 3 to 10 carbon atoms, a heterocyclic amino group having 3 to 10 carbon atoms, a heteroaryl amino group having 6 to 12 carbon atoms, an alkylsilylamino group having 2 to 10 carbon atoms, an azido group, and a halogen.

[0076] The thin film can be one of a metal oxide, a metal nitride, a metal sulfide, or a metal.

[0077] The thin film can be one of a non-metal oxide, a non-metal nitride, a non-metal sulfide, or a non-metal.

[0078] The method can be performed at a temperature above a dissociation temperature of the adduct precursor.

[0079] The method can be performed at 50 to 700°C.

[0080] Disclosed is a method of manufacturing a volatile memory device, the method including the above-described method of forming a thin film.

[0081] Disclosed is a method of manufacturing a non-volatile memory device, the method including the above-described method of forming a thin film.

[0082] Inventive effect

[0083] According to the present application, a layer containing Si or metal can be formed by filling the gap portion from the lower to the upper. Further, even if the process conditions are adjusted for each cycle, or there is no surface modification (such as plasma or chemical modification), different deposition thicknesses can be achieved in the upper and lower portions by the usual ALD. Further, by achieving gap filling without defects, the electrical characteristics can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0084] Figure 1 is a schematic cross-sectional view of a substrate having a gap portion.

[0085] Figure 2 is a 1H-NMR chart of the precursor TMA-EMS based on Embodiment 1 of the present application.

[0086] Figure 3 and Figure 4 is a chart showing the results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) tests of Embodiment 1.

[0087] Figure 5 is a chart showing the GPC (Growth Per Cycle) of the aluminum oxide film with respect to the process temperature based on Comparative Example 1 and Embodiment 1 of the present application.

[0088] Figure 6 is a confirmation result of the step coverage of the deposition of the aluminum oxide film to a pattern wafer at a process temperature of 400°C based on Comparative Example 1 of the present application (aspect ratio 20:1).

[0089] Figure 7 is a confirmation result of the step coverage of the deposition of the aluminum oxide film to a pattern wafer at a process temperature of 400°C based on Embodiment 1 of the present application (aspect ratio 20:1). DETAILED DESCRIPTION

[0090] Hereinafter, an embodiment of the present application will be described with reference to Figures 1-6 The embodiments of the present application can include various modifications, and the scope of the present application should not be construed as being limited to the following embodiments.

[0091] The precursor based on the embodiment of the present application exists in a stable adduct state in combination with an organic substance at the temperature / pressure in the chamber, but, in the cavity, dissociates before being adsorbed to the surface of the substrate due to heat energy, collision, etc.

[0092] Further, in the upper portion of the gap portion, the reactivity of the precursor is reduced due to the increase in size and the blocking effect, and thus the adsorption density is reduced. In the lower portion of the gap portion, the organic matter is removed by dissociation, and the metal and nonmetal compounds are adsorbed by themselves to increase the adsorption density. In particular, the deposition thickness is increased, and thus the gap filling from the bottom to the top can be performed.

[0093] Further, since the GPC is different in the upper and lower portions according to the depth of the gap portion, even in a structure having a high aspect ratio, gap filling without defects can be achieved.

[0094] According to an embodiment of the present application, a method of depositing a thin film includes the steps of supplying an adduct precursor to the inside of a chamber in which a substrate is placed, purifying the inside of the chamber, and supplying a reaction material to the inside of the chamber, so that the reaction material reacts with the adduct precursor to form a thin film. The adduct precursor is supplied to form the thin film at 50 to 700°C.

[0095] The substrate has one or more gap portions. The gap portion can be an opening or a cavity provided between inclined side walls of one or more non-planar surfaces. The gap portion can be an opening or a cavity provided between two inclined side walls of a pair of protrusions vertically extended from a surface of the substrate. The gap portion can be an opening or a cavity provided between one or more inclined side walls of a pair of recesses vertically extended from a surface of the substrate.

[0096] Figure 1 is a schematic cross-sectional view of a substrate having a gap portion. At least one gap portion 210 forms an opening on a surface 220 of the substrate. The gap portion 210 extends from the surface 220 of the substrate to a bottom surface 212 by a depth D. The gap portion 210 has a first side wall 214 and a second side wall 216, and the width W of the gap portion 210 is defined by the first side wall 214 and the second side wall 216. An open area formed by the side walls and the lowermost portion is also referred to as a gap.

[0097] The substrate is exposed to the adduct precursor supplied to the inside of the chamber, and the adduct precursor is adsorbed onto the gap portion of the substrate.

[0098] According to an embodiment of the present application, the adduct precursor is formed by mixing 1 to 5 moles of a compound represented by the following Chemical Formula 1 or the following Chemical Formula 2 with 1 to 5 moles of a metal compound.

[0099] <Chemical Formula 1>

[0100]

[0101] wherein X is O or S, and R1or R2is each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0102] <Chemical Formula 2>

[0103]

[0104] wherein X is O or S, n is 1 to 5, and R1to R4are each independently selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0105] The adduct precursor can be formed by mixing the metal compound with ethyl methyl sulfide, ethyl propyl ether, or tetrahydrofuran.

[0106] The metal compound can include at least one of Group 4 elements of Zr, Hf, and Ti as a central element.

[0107] The metal compound can be represented by the following Chemical Formula 3.

[0108] <Chemical Formula 3>

[0109]

[0110] wherein M is selected from metal elements belonging to Group 4 of the periodic table,

[0111] Each L is the same or different from each other, and is selected from a hydrogen atom, a straight chain / branched chain / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0112] The metal compound can be represented by the following Chemical Formula 4.

[0113] <Chemical Formula 4>

[0114]

[0115] wherein M is selected from metal elements belonging to Group 4 of the periodic table.

[0116] R1, R2, R3, R4, and R5are each independently selected from a hydrogen atom, a straight chain / branched chain / cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a phenyl group having 6 to 12 carbon atoms.

[0117] Each L is the same or different, and is selected from a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0118] When L is a dialkylamino group, the dialkylamino groups are connected to each other to form a cyclic amino group having 3 to 10 carbon atoms.

[0119] The metal compound can include at least one of Group 5 elements of Nb and Ta as a central element.

[0120] The metal compound can be represented by the following Chemical Formula 5 or the following Chemical Formula 6.

[0121] <Chemical Formula 5>

[0122]

[0123] <Chemical Formula 6>

[0124]

[0125] wherein M is selected from metal elements belonging to Group 5 of the periodic table,

[0126] Each L is the same or different, and is selected from a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0127] The metal compound can be represented by the following Chemical Formula 7.

[0128] <Chemical Formula 7>

[0129]

[0130] wherein M is selected from metal elements belonging to Group 5 of the periodic table.

[0131] R1, R2, and R3 are each independently selected from a hydrogen atom and a linear / branched / cyclic alkyl group having 1 to 5 carbon atoms.

[0132] Each L is the same or different, and is selected from a hydrogen atom, a linear / branched / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0133] The metal compound includes at least one of Group 6 elements including W and Mo as a central element.

[0134] The metal compound is represented by the following Chemical Formula 8 or the following Chemical Formula 9.

[0135] <Chemical Formula 8>

[0136]

[0137] <Chemical Formula 9>

[0138]

[0139] wherein M is selected from metal elements belonging to Group 6 of the periodic table.

[0140] Each L is the same or different from each other, and is selected from a hydrogen atom, a straight chain / branched chain / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0141] The metal compound can include at least one of Group 13 elements including Al as a central element.

[0142] The metal compound is represented by the following Chemical Formula 10.

[0143] <Chemical Formula 10>

[0144]

[0145] wherein M is selected from metal elements belonging to Group 13 of the periodic table.

[0146] Each L is the same or different from each other, and is selected from a hydrogen atom, a straight chain / branched chain / cyclic alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an amino group having 1 to 5 carbon atoms, a dialkylamino group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, and a halogen element.

[0147] According to another embodiment of the present application, the adduct precursor is formed by mixing 1 to 5 moles of a compound represented by the following Chemical Formula 1 or the following Chemical Formula 2 with 1 to 5 moles of a non-metal compound.

[0148] <Chemical Formula 1>

[0149]

[0150] wherein X is O or S, and R1or R2is each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0151] <Chemical Formula 2>

[0152]

[0153] wherein X is O or S, n is 1 to 5, and R1to R4are each independently selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

[0154] The adduct precursor is formed by mixing the metal compound with ethyl methyl sulfide, ethyl propyl ether, or tetrahydrofuran.

[0155] The non-metal compound has at least one of group 14 elements including Si and Ge as a central element.

[0156] The non-metal compound is represented by the following Chemical Formula 11

[0157] <Chemical Formula 11>

[0158]

[0159] wherein M is one of group 14 elements including Si and Ge.

[0160] R1to R4are each selected from a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 1 to 10 carbon atoms, an arylamino group having 6 to 12 carbon atoms, an aralkylamino group having 7 to 13 carbon atoms, a cyclic amino group having 3 to 10 carbon atoms, a heterocyclic amino group having 3 to 10 carbon atoms, a heteroaryl amino group having 6 to 12 carbon atoms, an alkylsilylamino group having 2 to 10 carbon atoms, an azide group, and a halogen.

[0161] The non-metal compound is represented by the following Chemical Formula 12.

[0162] <Chemical Formula 12>

[0163]

[0164] wherein M is one of group 14 elements including Si and Ge.

[0165] R1to R4are each selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkylamino group having 1 to 10 carbon atoms, a dialkylamino group having 1 to 10 carbon atoms, an arylamino group having 6 to 12 carbon atoms, an aralkylamino group having 7 to 13 carbon atoms, a cyclic amino group having 3 to 10 carbon atoms, a heterocyclic amino group having 3 to 10 carbon atoms, a heteroaryl amino group having 6 to 12 carbon atoms, an alkylsilylamino group having 2 to 10 carbon atoms, an azido group, and a halogen.

[0166] The metal / non-metal compound can exist in the form of a dimer or an oligomer at the temperature and pressure in the chamber, and the dimer or oligomer can be maintained even after the formation of the adduct precursor.

[0167] Thereafter, a purge gas (for example, an inert gas such as Ar) is supplied to the inside of the chamber to discharge unabsorbed surface protective substances or by-products.

[0168] Thereafter, the substrate is exposed to a reaction substance supplied to the inside of the chamber, and a thin film is formed on the surface of the substrate to fill the gap portion. The reaction substance reacts with the adduct precursor layer to form a thin film. When the reaction substance is O3, O2, or H2O gas, the thin film is a metal / non-metal oxide film. When the reaction substance is ammonia (NH3), hydrazine (N2H4), nitrogen dioxide (NO2), and nitrogen (N2), the thin film is a metal / non-metal nitride film. In addition, the thin film can be a metal / non-metal sulfide or metal / non-metal.

[0169] Thereafter, a purge gas (for example, an inert gas such as Ar) is supplied to the inside of the chamber to discharge unabsorbed surface protective substances or by-products.

[0170] Example 1

[0171] In a 500 ml round flask, 10.56 g (0.139 mol) of ethyl methyl sulfide corresponding to <Chemical Formula 1> was added to a storage tank at room temperature, and 5 g (0.069 mol) of trimethylaluminum corresponding to <Chemical Formula 6> was added very slowly to obtain a precursor TMA-EMS.

[0172] Figure 2 is a 1H-NMR chart of the precursor TMA-EMS based on Example 1 of the present application, showing the nuclear magnetic resonance spectrum of Example 1 / ethyl methyl sulfide / trimethylaluminum.

[0173] Trimethylaluminum: δ -0.36 (s)

[0174] Ethyl methyl sulfide: δ 2.19 (q), 1.76 (s), 1.20 (t)

[0175] TMA-EMS: δ -0.37 (s), δ 2.05 (q), 1.58 (s), 0.85 (t)

[0176] The peaks of chemical shifts δ = 2.19 ppm, 1.76 ppm and 1.20 ppm generated from ethyl methyl sulfide are shifted to 2.05 ppm, 1.58 ppm and 0.85 ppm, respectively, without changing the shape of the peaks even after the formation of the precursor TMA-EMS.

[0177] It is known that the peak of chemical shift δ = -0.36 ppm generated from trimethylaluminum is also finely shifted without changing its shape to form a stable precursor after the formation of the precursor TMA-EMS.

[0178] - Thermal analysis

[0179] Figure 3 and Figure 4 are graphs showing the results of differential scanning calorimetry (DSC) test and thermogravimetric analysis (TGA) test of Example 1. The differential scanning calorimetry (DSC) test and thermogravimetric analysis (TGA) test were performed on the TMA-EMS obtained in Example 1, and the thermal analysis test conditions for measuring the thermal decomposition temperature in each test were as follows.

[0180] Carrier gas: argon (Ar)

[0181] Carrier gas flow rate: 200 ml / min

[0182] Heating profile: heating from 30°C to 400°C at a heating rate of 10°C / min

[0183] In the DSC test, the thermal decomposition temperature was determined as the temperature of the point at which the heat flow suddenly increased as the temperature increased in the DSC thermogram.

[0184] As can be seen with reference to [Table 1] below, the TMA-EMS all have excellent vaporization characteristics, and the amount of residual components is 0.1% or less, leaving no impurities in the thin film. In addition, the decomposition temperature of the TMA-EMS is about 340°C, showing improved thermal stability compared to trimethylaluminum (TMA) which has a decomposition temperature of about 320°C. This can be considered as the formation of a stable molecule by effectively blocking the Al-Al interaction between TMAs by the organic molecule. In addition, it can be expected that the addition of the adduct increases the steric hindrance around the Al center, as a result, the reactivity is reduced compared to TMA before the addition of the adduct.

[0185] [Table 1]

[0186]

[0187] The diameter of the TMA-EMS precursor is about This is significantly larger than the TMA diameter This not only further reduces the accessibility of the Al center and the surface -OH* of the TMA-EMS precursor, but also since the steric hindrance plays a greater role when some adsorbed precursor exists on the surface, the deposition thickness per cycle is reduced step by step. This can be confirmed by the deposition results using the TMA-EMS precursor in Figure 5

[0188] Also, the TMA-EMS precursor can form a uniform thin film due to the reduced reactivity with the -OH* end group on the surface, reduced sticking coefficient, and increased diffusion on the surface, and finally, the uniformity and step coverage are improved.

[0189] - Comparative Example 1

[0190] An aluminum oxide film was formed on a silicon substrate. The aluminum oxide film was formed by an ALD process, the temperature of which was 250 to 400°C, and O3 gas was used as a reaction material.

[0191] The process of forming the aluminum oxide film by the ALD process was as follows, and the following process was performed as one cycle.

[0192] 1) Ar was used as a carrier gas, and an aluminum precursor TMA (trimethylaluminum) was supplied to the reaction chamber at room temperature, and the aluminum precursor was adsorbed onto the substrate.

[0193] 2) Ar was supplied to the reaction chamber to discharge the aluminum precursor or by-products that were not adsorbed.

[0194] 3) O3 gas was supplied to the reaction chamber to form a monolayer.

[0195] 4) Ar was supplied to the reaction chamber to discharge unreacted materials or by-products.

[0196] The results of measuring the thickness of the aluminum oxide film obtained by the above process were that the thickness of the aluminum oxide film obtained for each cycle of the ALD process was about cycles at 250 to 400°C.

[0197] Figure 5 is a graph showing the GPC (Growth Per Cycle) of the aluminum oxide film with respect to the process temperature based on Comparative Example 1 and Example 1 of the present application. As Figure 5 ​As shown, within a substrate temperature range of 250–400 °C, GPC exhibits ideal ALD behavior with minimal change as the substrate temperature increases. Assuming the total thickness of the dielectric film in the ZrO2 / Al2O3 / ZrO2 composite dielectric film of the DRAM is... Furthermore, since Al2O3 in Comparative Example 1 was used for approximately 3 cycles, the EOT of the dielectric film was...

[0198] Example 1

[0199] An alumina film was formed on a silicon substrate using the precursor TMA-EMS based on Example 1 of the present invention. Except for replacing the precursor, the alumina film was formed in the same manner as in Comparative Example 1.

[0200] The thickness of the alumina film obtained through the above process was measured, and at 250–400°C, the thickness of the alumina film obtained in each cycle of the ALD process was approximately... cycle.

[0201] In addition, such as Figure 5 As shown, within a substrate temperature range of 250–400°C, GPC exhibits ideal ALD behavior with minimal change as the substrate temperature increases, and shows a reduction of approximately 20% compared to Comparative Example 1. Assuming the total thickness of the dielectric film in the ZrO2 / Al2O3 / ZrO2 composite dielectric film of the DRAM is... Furthermore, since Al2O3 in Example 2 is used for approximately 3 cycles, the EOT of the dielectric film is... Ensure that it is scaled down by approximately 4% compared to Comparative Example 1.

[0202] Figure 6 This is a confirmation result (aspect ratio 20:1) of the step coverage of an alumina film deposited on a patterned wafer at a process temperature of 400°C, based on Comparative Example 1 of the present invention. Figure 6 As shown, the thickness of the upper part is obtained by repeating the process for a certain period of time. The thickness of the lower part is 100% step coverage was confirmed.

[0203] Figure 7 This is a confirmation result (aspect ratio 20:1) of the step coverage of an alumina film deposited on a patterned wafer at a process temperature of 400°C, based on Embodiment 1 of the present invention. Figure 7 As shown, the thickness of the upper part is obtained by repeating the cycle process. The thickness of the bottom is The results confirmed that the step coverage was 116%, and it was also confirmed that the thickness in the lower part increased by 15% compared to the upper part.

[0204] On the flat plate, the adduct precursor in the structure is apt to dissociate unlike the ideal ALD behavior. A process temperature higher than the dissociation temperature of the adduct precursor can be explained as providing energy sufficient to break the bond between the metal / nonmetal compound and the organic compound. Diffusion toward the bottom in the structure and an increase in the number of collisions between molecules can be explained as a cause of dissociation of the adduct precursor.

[0205] As a result, the dissociated organic matter has relatively high volatility, thereby existing in a high density in the upper portion, and the metal / nonmetal compound having relatively low volatility and being heavy can exist in a high density in the lower portion. The metal / nonmetal compound existing in a high density in the bottom restores the original reactivity by removing the blocking effect of the organic matter, thereby depositing at a high growth rate, and in turn increasing the thickness.

[0206] In summary, by using the adduct precursor of the present application, a gradient absorption characteristic in which the deposition rate increases toward the bottom can be obtained. Also, when the process is performed repeatedly for a plurality of cycles, gap filling without defects can be achieved even in a structure having a high aspect ratio filled from the bottom upward.

[0207] The present application has been described in detail with reference to the reference examples, but can include other examples. Accordingly, the technical idea and scope recited in the following claims are not limited to the above-described examples.

Claims

1. A method for depositing a thin film, the method comprising: The steps of preparing an adduct precursor by mixing 1 to 5 moles of a compound represented by chemical formula 1 or chemical formula 2 below and 1 to 5 moles of a metal compound; The step of supplying the adduct precursor into a cavity containing a substrate having at least one slit, thereby adsorbing the adduct precursor onto the substrate. The steps of purifying the interior of the cavity; and The step of supplying reactants into the interior of the cavity, whereby the reactants react with the adduct precursor to form a thin film that fills the gaps. <Chemical Formula 1> Wherein, X is O or S, and R1 or R2 are each independently selected from alkyl groups having 1 to 3 carbon atoms. <Chemical Formula 2> Where X is O, n is 3 or 4, and R1 to R4 are each independently selected from hydrogen atoms and alkyl groups having 1 to 3 carbon atoms.

2. The method for depositing a thin film as described in claim 1, wherein, The adduct precursor is formed by mixing the metal compound with ethyl methyl sulfide, ethyl propyl ether, or tetrahydrofuran.

3. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound uses at least one of the four group elements, including Zr, Hf and Ti, as its center element.

4. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound is represented by the following chemical formula 3. <Chemical Formula 3> M is selected from the metallic elements belonging to Group 4 of the periodic table. Each L may be the same or different from the others, and is selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, amino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 13 carbon atoms, and halogen elements.

5. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound is represented by the following chemical formula 4. <Chemical Formula 4> M is selected from the metallic elements belonging to Group 4 of the periodic table. R1, R2, R3, R4, and R5 are each independently selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 5 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, and phenyl groups having 6 to 12 carbon atoms. Each L may be the same or different, and is selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, amino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms. When L is a dialkylamino group, they connect with each other to form a cyclic amino group with 3 to 10 carbon atoms.

6. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound uses at least one of the group 5 elements, including Nb and Ta, as its center element.

7. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound is represented by chemical formula 5 or chemical formula 6 below. <Chemical Formula 5> <Chemical Formula 6> M is selected from the metallic elements belonging to Group 5 of the periodic table. Each L may be the same or different from the others, and is selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, amino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 13 carbon atoms, and halogen elements.

8. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound is represented by the following chemical formula 7. <Chemical Formula 7> M is selected from the metallic elements belonging to Group 5 of the periodic table. R1, R2, and R3 are each independently selected from hydrogen atoms and straight-chain / branched / cyclic alkyl groups having 1 to 5 carbon atoms. Each L may be the same or different from the others, and is selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, amino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 13 carbon atoms, and halogen elements.

9. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound has at least one of the group 6 elements, including W and Mo, as its center element.

10. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound is represented by chemical formula 8 or chemical formula 9 below. <Chemical Formula 8> <Chemical Formula 9> M is selected from the metallic elements belonging to Group 6 of the periodic table. Each L may be the same or different from the others, and is selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, amino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 13 carbon atoms, and halogen elements.

11. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound has at least one of the group 13 elements, including Al, as its central element.

12. The method for depositing a thin film as described in claim 1 or 2, wherein, The metal compound is represented by the following chemical formula 10. <Chemical Formula 10> M is selected from the metallic elements belonging to group 13 of the periodic table. Each L may be the same or different from the others, and is selected from hydrogen atoms, straight-chain / branched / cyclic alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, amino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, aralkyl groups having 7 to 13 carbon atoms, and halogen elements.

13. A method for depositing a thin film, the method comprising: The steps of preparing an adduct precursor by mixing 1 to 5 moles of a compound represented by chemical formula 1 or chemical formula 2 below and 1 to 5 moles of a nonmetallic compound; The step of supplying the adduct precursor into a cavity containing a substrate having at least one slit, thereby adsorbing the adduct precursor onto the substrate. The steps of purifying the interior of the cavity; and The step of supplying reactants into the interior of the cavity, whereby the reactants react with the adduct precursor to form a thin film that fills the gaps. The nonmetallic compound uses at least one of group 14 elements, including Si and Ge, as its central element. <Chemical Formula 1> Wherein, X is O or S, and R1 or R2 are each independently selected from alkyl groups having 1 to 3 carbon atoms. <Chemical Formula 2> Where X is O, n is 3 or 4, and R1 to R4 are each independently selected from hydrogen atoms and alkyl groups having 1 to 5 carbon atoms.

14. The method for depositing a thin film as described in claim 13, wherein, The adduct precursor is formed by mixing the metal compound with ethyl methyl sulfide, ethyl propyl ether, or tetrahydrofuran.

15. The method for depositing a thin film as described in claim 13, wherein, The nonmetallic compound is represented by the following chemical formula 11. <Chemical Formula 11> M is one of the elements in group 14, which includes Si and Ge. R1 to R4 are each selected from hydrogen atoms, alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 12 carbon atoms, alkylamino groups having 1 to 10 carbon atoms, dialkylamino groups having 1 to 10 carbon atoms, aromaticamino groups having 6 to 12 carbon atoms, aromaticalkylamino groups having 7 to 13 carbon atoms, cyclicamino groups having 3 to 10 carbon atoms, heterocyclicamino groups having 3 to 10 carbon atoms, heteroaromaticamino groups having 6 to 12 carbon atoms, alkylsilaneamino groups having 2 to 10 carbon atoms, azide groups, and halogens.

16. The method for depositing a thin film as described in claim 13, wherein, The nonmetallic compound is represented by the following chemical formula 12. <Chemical Formula 12> M is one of the elements in group 14, which includes Si and Ge. R1 to R6 are each independently selected from hydrogen atoms, alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 12 carbon atoms, alkylamino groups having 1 to 10 carbon atoms, dialkylamino groups having 1 to 10 carbon atoms, aromaticamino groups having 6 to 12 carbon atoms, aromaticalkylamino groups having 7 to 13 carbon atoms, cyclicamino groups having 3 to 10 carbon atoms, heterocyclicamino groups having 3 to 10 carbon atoms, heteroaromaticamino groups having 6 to 12 carbon atoms, alkylsilaneamino groups having 2 to 10 carbon atoms, azide groups, and halogens.

17. The method for depositing a thin film as described in claim 1 or 2, wherein, The thin film is one of a metal oxide, a metal nitride, a metal sulfide, or a metal.

18. The method for depositing a thin film as described in claim 13 or 14, wherein, The thin film is one of a non-metallic oxide, a non-metallic nitride, a non-metallic sulfide, or a non-metal.

19. The method for depositing a thin film as described in claims 1, 2, 13, and 14, wherein, The method is carried out at a temperature above the dissociation temperature of the adduct precursor.

20. The method for depositing a thin film as described in claims 1, 2, 13, and 14, wherein, The method is carried out at 50–700°C.

21. A method for manufacturing a volatile storage device, comprising the method for forming a thin film as described in any one of claims 1, 2, 13, and 14.

22. A method for manufacturing a non-volatile storage device, comprising the method for forming a thin film as described in any one of claims 1, 2, 13, and 14.

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