Muti-chamber system for atomic layer etching processes

Abstract

The present invention relates to a multi-chamber system for an atomic layer etching process. A multi-chamber system according to one embodiment of the present invention comprises: a first chamber for modifying a metal film formed on a substrate; a second chamber for etching the metal film modified in the first chamber in atomic layer units; and a control unit. The first chamber comprises a plasma generation unit for generating plasma in a processing space of the first chamber; and a gas supply unit for selectively supplying process gas and a precursor to the processing space. The second chamber comprises a heating unit for supplying heat to a processing space of the second chamber. The control unit controls the plasma generation unit, the gas supply unit, and the heating unit to etch the metal film modified in the first chamber in atomic layer units in the second chamber.

Description

Technology Field

[0001] The present invention relates to a multi-chamber system for performing an atomic layer etching process. More specifically, it relates to a multi-chamber system for performing a process of modifying a metal film formed on a substrate and a process of etching the modified metal film at the atomic layer level in different chambers. Background Technology

[0003] Recently, as semiconductor devices have become more miniaturized, wiring has also been miniaturized. However, as miniaturization progresses further, new problems are emerging regarding copper (Cu) wiring. Specifically, as the linewidth of the wiring decreases, the dimensions of the copper (Cu) wiring also decrease proportionally, resulting in the dimensions of the copper wiring shrinking to a level lower than the Electron Mean Free Path (EMFP) of 39 nm in the bulk state of copper. Consequently, the resistivity of the copper wiring has increased rapidly. For example, it has been reported that when the linewidth of the copper wiring is reduced to 10 nm, the resistivity of the wiring rises to approximately 10 times that of the bulk resistivity. This severe increase in resistivity causes semiconductor power consumption and speed delays, thereby limiting the performance of semiconductor devices and hindering continuous device scaling.

[0004] Due to these issues, ruthenium (Ru) is attracting attention as a next-generation wiring material. Although ruthenium has a high melting point and bulk resistivity that is not as low as copper's, its average electron mobility is shorter than that of copper, making it suitable for use as a wiring material. This ruthenium is utilized as wiring after undergoing an etching process.

[0005] In the past, a reactive ion etching (RIE) method has been used to etch ruthenium, as described in Public Patent No. 10-2017-0019035, "Method for Etching Ruthenium Thin Films" (Published on Feb. 21, 2017). However, when etching a ruthenium thin film using a reactive ion etching method, roughness is induced on the surface of the thin film by ions, which increases the likelihood of leakage current generation and thus affects the product yield.

[0006] In addition, if the substrate is exposed to high temperatures for a long time as the etching process proceeds, problems such as modification of the ruthenium thin film formed on the substrate or changes in the shape of the pattern formed on the substrate occur.

[0007] Therefore, new etching technology for ruthenium thin films is required to solve these problems. The problem to be solved

[0009] The present invention aims to solve conventional problems by providing an atomic layer etching (ALE) process that minimizes substrate deformation caused by temperature during the process and reduces damage to the thin film during the etching process.

[0010] The problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art from the description below. means of solving the problem

[0012] A multi-chamber system according to one embodiment of the present invention comprises: a first chamber for modifying a metal film formed on a substrate; a second chamber for etching the metal film modified in the first chamber in atomic layer units; and a control unit, wherein the first chamber comprises a plasma generation unit for generating plasma in a processing space of the first chamber; and a gas supply unit for selectively supplying process gas and a precursor to the processing space, and the second chamber comprises a heating unit for supplying heat to a processing space of the second chamber, and the control unit can control the plasma generation unit, the gas supply unit, and the heating unit to etch the metal film modified in the first chamber in the second chamber in atomic layer units.

[0013] In one embodiment, the metal film formed on the substrate may include ruthenium.

[0014] In one embodiment, the control unit can control the plasma generation unit and the gas supply unit to sequentially supply a plasma-generated process gas and a precursor to the processing space of the first chamber to modify the metal film.

[0015] In one embodiment, the process gas contains oxygen, and the precursor may be a beta-diketone (β-diketone).

[0016] In one embodiment, the control unit can control the heating unit to supply heat of 300°C or higher to the processing space of the second chamber to etch the modified metal film in atomic layer units.

[0017] A method for atomic layer etching of a metal film formed on a substrate using a multi-chamber system comprising a first chamber and a second chamber according to an embodiment of the present invention may include: a modification process for modifying the metal film formed on the substrate in the first chamber; and an etching process for etching the metal film modified in the first chamber in atomic layer units in the second chamber.

[0018] In one embodiment, the metal film comprises ruthenium, and the modification process comprises: a first step of supplying a process gas containing oxygen to a processing space of a first chamber in which the substrate is disposed and plasmaizing the process gas to oxidize the metal film formed on the substrate; a second step of supplying a purge gas to remove the process gas remaining in the processing space; a third step of supplying a beta-diketone (β-diketone) precursor to the processing space to modify the metal film oxidized by the first step; and a fourth step of supplying a purge gas to remove the precursor remaining in the processing space, and the etching process may include a fifth step of supplying heat to a processing space of a second chamber in which the modified substrate is disposed to etch the modified metal film in atomic layer units.

[0019] In one embodiment, the modification process to the etching process is performed as one cycle and can be repeated at least once.

[0020] In one embodiment, the modification process can be performed at a lower temperature than the etching process.

[0021] In one embodiment, the etching process may be performed at a temperature of 300°C or higher. Effects of the invention

[0023] According to the present invention, by performing the process of modifying a ruthenium thin film and the process of etching the modified thin film in different chambers, substrate deformation due to temperature can be minimized.

[0024] In addition, by etching the modified ruthenium thin film using an atomic layer etching (ALE) process, the etching amount can be easily controlled and thin film surface damage reduced, thereby improving product yield.

[0025] However, the effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the drawings below. Brief explanation of the drawing

[0027] FIG. 1 is a plan view of a multi-chamber system according to one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a multi-chamber configuration according to one embodiment of the present invention. FIG. 3 is a cross-sectional view of a first chamber according to one embodiment of the present invention. FIG. 4 is a cross-sectional view of a second chamber according to one embodiment of the present invention. FIG. 5 is a process flow diagram according to one embodiment of the present invention. Specific details for implementing the invention

[0028] Hereinafter, embodiments of the present invention are described in detail with reference to the attached drawings so that a person skilled in the art can easily implement the present invention. However, the present invention may be embodied in various other forms and is not limited to the embodiments described herein.

[0029] In describing embodiments of the present invention, if it is determined that a specific description of related known functions or configurations may unnecessarily obscure the essence of the present invention, such specific description is omitted, and parts having similar functions and operations are denoted by the same reference numerals throughout the drawings.

[0030] At least some of the terms used in the specification are defined with consideration of their functions in the present invention and may vary depending on the user's or operator's intent, convention, etc. Therefore, such terms should be interpreted based on the content throughout the specification.

[0031] Additionally, in this specification, the singular form includes the plural form unless specifically stated otherwise in the text. In this specification, when a component is described as including, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0032] Although terms such as 'first' and 'second' are intended to distinguish one component from another, the scope of rights must not be limited by these terms. For example, the first component may be named the second component, and similarly, the second component may be named the first component.

[0033] Meanwhile, the size, shape, and line thickness of components in the drawings may be depicted somewhat exaggerated for ease of understanding.

[0034] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. In describing with reference to the attached drawings, identical or corresponding components are given the same reference number regardless of the drawing symbols, and redundant descriptions thereof will be omitted.

[0036] A substrate according to one embodiment of the present invention may be a silicon substrate based on a semiconductor wafer. In this case, a metal film may be formed on the substrate, and the formed metal film may be a ruthenium (Ru) thin film.

[0038] FIG. 1 is a plan view of a multi-chamber system according to one embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view showing the configuration of a multi-chamber according to one embodiment of the present invention.

[0039] Referring to FIGS. 1 and 2, the semiconductor manufacturing facility may include an index block (10), a processing block (20), and a substrate transfer block (30) for transferring a substrate between the index block (10) and the processing block (20). According to one embodiment of the present invention, the index block (10) and the processing block (20) may be arranged sequentially in a line.

[0040] The index block (10) may include a load port (12) on which a carrier (C) containing a substrate is placed, and an index frame (14) for withdrawing a substrate (W) from the carrier (C) placed on the load port (12) or for bringing in a substrate that has completed process processing into the carrier (C). The load port (12) is located on the opposite side of the processing block (20) relative to the index frame (14). A plurality of carriers (C) containing substrates (W) are placed in the load port (12).

[0041] An index robot (144) may be provided inside the index frame (14). The index robot (144) may be provided to be movable along a rail (142). The index robot (144) may receive a substrate from the carrier (C) and transfer it to a load lock chamber (15) where the substrate is temporarily stored, or receive a substrate temporarily stored in the load lock chamber (15) and transfer it to the interior of the carrier (C).

[0042] The processing block (20) is a device for performing process processing on a substrate and may include one or more process processing chambers (200). Multiple process processing chambers (200) may be arranged. Each process processing chamber (200) may perform the same process or perform different processes. Referring to FIG. 2, according to one embodiment of the present invention, the first chamber (200a) may perform a modification process for modifying a metal film formed on a substrate, and the second chamber (200b) may perform an etching process for etching the modified metal film. These process processing chambers (200a, 200b) will be described in detail later. Furthermore, according to one embodiment of the present invention, the first chamber (200a) and the second chamber (200b) are shown as being arranged adjacent to each other to perform the process, but this is not limited thereto. For example, the first chamber (200a) and the second chamber (200b) may be positioned opposite each other or spaced apart on the same line.

[0043] A substrate transfer block (30) is positioned adjacent to a processing block (20) and can receive a substrate from a load lock chamber (15) and transfer it to the processing block (20), or transfer a substrate that has completed process processing in the processing block (20) to the load lock chamber (15). The substrate transfer block (30) may include a rail (330) positioned along the direction in which the process processing chamber (200) is positioned, and a substrate transfer robot (340) that transfers the substrate while moving along the rail (330). The substrate transfer robot (340) can transfer the substrate while moving within the internal space of the return chamber (310).

[0045] FIG. 3 is a schematic cross-sectional view of a first chamber according to one embodiment of the present invention.

[0046] Referring to FIG. 3, the first chamber (200a) may include a substrate support unit (400), a plasma generation unit (500), a gas supply unit (600), and a control unit (800).

[0047] The first chamber (200a) has a processing space where a substrate (W) is placed and a plasma process is performed. An opening (not shown) may be formed in the side wall of this chamber (200a). The substrate may enter and exit the chamber (200a) through the opening (not shown). The opening (not shown) may be opened and closed by an opening / closing member such as a door. An exhaust hole (202) may be formed on the bottom surface of the chamber (200a). The exhaust hole (202) may provide a passage for gases and reaction byproducts remaining in the processing space inside the chamber (200a) to be discharged to the outside.

[0048] A substrate support unit (400) for supporting a substrate (W) may be provided inside the chamber (200a). The substrate support unit (400) may include a susceptor (402) and a support shaft (404). The susceptor (402) is placed within the processing space of the chamber (200a) and may be provided in the shape of a disc. The susceptor (402) may be supported by the support shaft (404). The substrate (W) may be placed on the upper surface of the susceptor (402), and an electrode (not shown) may be formed inside the susceptor (402). The electrode (not shown) is connected to an external power source (not shown) and may generate static electricity by the applied power. The generated static electricity may fix the substrate (W) to the susceptor (402). A heating member (422) may be provided inside the susceptor (402). For example, the heating element (422) may be a heating coil. Additionally, a cooling element (442) may be provided inside the susceptor (402). The cooling element (442) may be provided as a cooling line through which cooling water flows. The heating element (422) can heat the substrate (W) to a preset temperature, and the cooling element (442) can forcibly cool the substrate (W). The substrate (W) after the process is completed may be cooled or heated to a room temperature or to a temperature required for the next process.

[0049] A plasma generation unit (500) can generate plasma in the processing space of a chamber (200a). Plasma can be formed in the upper region of a substrate support unit (400) within the chamber (200a). According to one embodiment of the present invention, the plasma generation unit (500) can generate plasma in the processing space inside the chamber (200a) using an inductively coupled plasma (ICP) source, but the present invention is not limited thereto. As an example, the plasma generation unit (500) can generate plasma in the processing space inside the chamber (200a) using a capacitively coupled plasma (CCP) source or microwaves.

[0050] A plasma generation unit (500) may be configured to include an upper power supply (510) and an antenna unit (520). The upper power supply (510) may supply power to the antenna unit (520). This upper power supply (510) may be provided to control the characteristics of the plasma. The upper power supply (510) may be provided, for example, to control the plasma density.

[0051] An antenna unit (520) may be installed on the side wall of the chamber (200a). The antenna unit (520) may include a coil provided to form a closed loop. The antenna unit (520) may function to excite the process gas introduced into the chamber (200a) into plasma based on power supplied from the upper power source (510).

[0052] The shower head (460) may be formed to face the susceptor (402) vertically inside the chamber (200a). This shower head (460) may be provided with a plurality of gas injection holes (462) to evenly spray gas into the chamber (200a) and may be provided to have a diameter larger than that of the susceptor (402). Meanwhile, the shower head (460) may be manufactured using a silicone component, and it is also possible to manufacture it using a metal component.

[0053] The gas supply unit (600) can supply gas required for the process to the chamber (200a). Specifically, the gas supply unit (600) can supply process gas containing oxygen, a beta-diketone (β-diketone) precursor, or purge gas to the processing space of the chamber (200a). The gas supply unit (600) may include a gas source (602), a gas supply line (604), and a gas injection nozzle. The gas supply line (604) can connect the gas source (602) and the gas injection nozzle. A valve (606) may be installed in the gas supply line (604) to open or close the passage or to control the flow rate of the fluid flowing through the passage.

[0054] Although only one gas supply source (602) and gas supply valve (606) are shown in FIG. 3, the gas supply source (602) of the present invention may include a plurality of gas supply sources and a plurality of gas supply valves capable of independently controlling the supply of each gas so as to supply a plurality of gases to the chamber (200a). The plurality of gases may include process gases used in the substrate processing process, beta-diketone (β-diketone) precursors, and inert gases for purging.

[0055] The control unit (800) can supply an oxygen-based process gas to the processing space inside the chamber (200a) and control the process gas to be plasmaized by the plasma generation unit (500). In addition, the control unit (800) can control the upper power supply (510) to turn on / off. Furthermore, the control unit (800) can control the transfer of the substrate, after the modification process is finished, to the second chamber (200b) in order to etch the metal film in atomic layer units.

[0056] That is, when the modification process of the metal film formed on the substrate (W) in the first chamber (200a) is completed, the substrate (W) on which the modification process is completed is moved to the second chamber (200b) by the substrate transfer robot (340) of the substrate transfer block (30) so that the modified metal film can be etched in atomic layer units. While the substrate (W) is being moved from the first chamber (200a) to the second chamber (200b), the substrate transfer block (30) can maintain a vacuum state.

[0058] FIG. 4 is a schematic diagram showing a second chamber according to an embodiment of the present invention. The second chamber can perform a process of etching a modified metal film at the atomic layer level using inert gas and heat without using plasma.

[0059] Referring to FIG. 4, the second chamber (200b) differs from the first chamber (200a) of FIG. 3 in that it does not use plasma, but instead uses a heating unit (700) to perform the substrate (W) etching process.

[0060] Referring to FIG. 4, a heating unit (700) may be provided on the upper side of the second chamber (200b) to etch the modified metal film in atomic layer units by supplying inert gas and heat. The heating unit (700) may be equipped with a plurality of heating lamps (710) that generate thermal energy and may supply heat to a substrate (W) placed on the opposite lower side. According to one embodiment of the present invention, the heating lamps (710) may be halogen lamps, and heat of 300°C or higher may be supplied to the substrate (W) using these lamps.

[0061] A window (720) may be formed between the heating lamp (710) and the substrate support unit (400). The window (720) may serve to protect the heating lamp (710) from being deposited with etching byproducts generated as the process proceeds. For example, the window (720) may be a dielectric window. The window (720) can transmit light wavelengths generated from the heating lamp (710) to supply heat to the substrate (W). That is, heat can be supplied from the heating unit (700) and at the same time, an inert gas can be supplied from the gas supply unit (600) to etch the modified metal film at the atomic layer level.

[0062] The control unit (800) can control the supply of inert gas from the gas supply unit (600) while the heating unit (700) supplies heat to the substrate (W) placed in the internal processing space of the chamber (200b). In addition, if etching is not performed to the desired thickness, the control unit (800) can transfer the substrate (W) after the etching process is finished to the first chamber (200a) to perform the modification process again.

[0063] The second chamber (200b) of the present invention having the above configuration is a Rapid Thermal Process (RTP) device and can be used when a rapid increase in temperature is required in a short period of time. In addition, the heating unit (700) provided in the second chamber (200b) is not limited to a heating lamp and may include other heat treatment means capable of rapid thermal processing. For example, the heating unit (700) may include a microwave generator, a laser generator, an infrared lamp, etc.

[0065] FIG. 5 is a process flow diagram of an atomic layer etching process using a multi-chamber system according to an embodiment of the present invention. Referring to FIG. 5, the atomic layer etching (ALE) process may include a modification process (S10) for modifying a metal film formed on a substrate and an etching process (S20) for etching the modified metal film.

[0066] A modification process (S10) for modifying a metal film formed on a substrate may include: a first step (S12) of supplying a process gas to a processing space where the substrate (W) is placed and plasmaizing the process gas to oxidize the metal film formed on the substrate (W); a second step (S14) of supplying a purge gas to remove the process gas remaining in the processing space; a third step (S16) of supplying a beta-diketone (β-diketone) precursor to the processing space to modify the metal film oxidized by the first step (S12); and a fourth step (S18) of supplying a purge gas to remove the precursor remaining in the processing space. Subsequently, an etching process (S20) for etching the modified metal film may include a fifth step (S22) of supplying heat to the processing space where the substrate (W) is placed after the modification process (S10) is completed to etch the modified metal film in atomic layer units.

[0067] According to one embodiment of the present invention, the modification process (S10) can be performed at a temperature of about 30°C, and the etching process (S20) can be performed at a temperature of 300°C or higher. The modification process (S10) and the etching process (S20) constitute one cycle, and the above five steps (S12 to S22) can be repeated to obtain a desired etching thickness.

[0069] The first step (S12) is a step of supplying process gas to a processing space of a first chamber (200a) where a substrate (W) is located using a gas supply unit (600), and plasmafiing the supplied process gas to oxidize a metal film formed on the substrate (W). The process gas according to one embodiment of the present invention may be a gas containing oxygen. The process gas, which is radicalized and ionized by a plasma generation unit (500), may react with ruthenium formed on the substrate (W) to produce a metal oxide layer. At this time, the thickness of the metal oxide layer produced is determined according to the oxidation conditions.

[0070] The second step (S14) is a step of supplying purge gas to the processing space of the first chamber (200a) where the substrate (W) is located using a gas supply unit (600). The purge gas can be supplied after the gas supply of the first step (S12) is stopped. The supply of purge gas can remove residual gas and reaction byproducts that remain in the processing space of the chamber (200a) after being supplied in the first step (S12). As an example, the purge gas may be an inert gas such as argon (Ar) or helium (He).

[0071] The third step (S16) is a step of modifying the metal film oxidized by the first step (S12) by supplying a beta-diketone precursor to the processing space of the first chamber (200a) using a gas supply unit (600). The beta-diketone precursor is physically adsorbed onto the metal oxide layer. Subsequently, the metal oxide layer formed on the substrate (W) is not etched through a ligand exchange reaction, but the binding energy can be weakened compared to before this step (S16) is performed.

[0072] Step 4 (S18) is a step of supplying purge gas to the processing space of the first chamber (200a) where the substrate (W) is located using a gas supply unit (600). The purge gas can be supplied after the gas supply of Step 3 (S16) is stopped. The supply of purge gas can remove precursors and reaction byproducts that remain in the processing space of the chamber (200a) after being supplied in Step 3 (S16). As an example, the purge gas may be an inert gas such as argon (Ar) or helium (He).

[0073] Step 5 (S22) is a step of etching the modified metal film in atomic layer units by supplying heat to the processing space of the second chamber (200b) in which the substrate (W) that has finished the modification process (S10) is placed. The modified metal film can be etched in atomic layer units by supplying heat to the substrate (W) using a heating unit (700) and simultaneously supplying an inert gas using a gas supply unit (600). According to one embodiment of the present invention, heat of 300°C or higher can be supplied to the substrate using a halogen lamp, and argon (Ar), helium (He), etc. can be used as the inert gas.

[0075] As described above, the atomic layer etching process using the multi-chamber system of the present invention can perform a modification process (S10) in which a substrate (W) is modified by supplying plasma-enhanced process gas and a precursor in the first chamber (200a), and perform an etching process (S20) in which the modified substrate (W) is etched by supplying heat in the second chamber (200b). Compared to performing the process in a single chamber in the conventional method, deformation of the substrate (W) due to temperature can be minimized by performing the process at different temperatures depending on the modification process (S10) and the etching process (S20). In addition, by modifying the metal film formed on the substrate (W) in the first chamber (200a) at a low temperature, the generation of toxic substances can be minimized. In the second chamber (200b), the modified metal film is etched at the atomic layer level using heat, thereby preventing damage to the thin film caused by ions. Furthermore, the control of the etching amount and the etching selectivity are improved, thereby improving the product yield.

[0077] The foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments described in the present invention are intended to explain, not limit, the technical concept of the present invention, and the technical concept of the present invention is not limited by these embodiments. The scope of protection of the present invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0079] W : Substrate 200a: First chamber 200b: Second chamber 400 : Substrate support unit 500: Plasma generation unit 600: Gas supply unit 700 : Heating unit 800: Control Unit

Claims

Claim 1 A multi-chamber system comprising: a first chamber for modifying a metal film formed on a substrate; a second chamber for etching the metal film modified in the first chamber in atomic layer units; and a control unit; wherein the first chamber comprises: a plasma generation unit for generating plasma in a processing space of the first chamber; and a gas supply unit for selectively supplying process gas and a precursor to the processing space; and the second chamber comprises: a heating unit for supplying heat to a processing space of the second chamber; and wherein the control unit controls the plasma generation unit, the gas supply unit, and the heating unit to etch the metal film modified in the first chamber in the second chamber in atomic layer units, and wherein the metal film formed on the substrate comprises ruthenium. Claim 2 delete Claim 3 A multi-chamber system according to claim 1, wherein the control unit controls the plasma generation unit and the gas supply unit to sequentially supply plasma-generated process gas and a precursor to the processing space of the first chamber to modify the metal film. Claim 4 A multi-chamber system according to paragraph 3, characterized in that the process gas contains oxygen and the precursor is beta-diketone (β-diketone). Claim 5 A multi-chamber system according to claim 1, wherein the control unit controls the heating unit to supply heat of 300°C or higher to the processing space of the second chamber to etch the modified metal film in atomic layer units. Claim 6 A method for atomic layer etching of a metal film formed on a substrate using a multi-chamber system comprising a first chamber and a second chamber, comprising: a modification process for modifying the metal film formed on the substrate in the first chamber; and an etching process for etching the metal film modified in the first chamber in atomic layer units in the second chamber; wherein the metal film comprises ruthenium. Claim 7 In claim 6, the modification process comprises: a first step of supplying a process gas containing oxygen to a processing space of a first chamber in which the substrate is disposed and plasmaizing the process gas to oxidize a metal film formed on the substrate; a second step of supplying a purge gas to remove the process gas remaining in the processing space; a third step of supplying a beta-diketone (β-diketone) precursor to the processing space to modify the metal film oxidized by the first step; and a fourth step of supplying a purge gas to remove the precursor remaining in the processing space; and the etching process comprises a fifth step of supplying heat to a processing space of a second chamber in which the modified substrate is disposed to etch the modified metal film in atomic layer units. Claim 8 An atomic layer etching method according to claim 6, characterized by performing the modification process to the etching process as one cycle and repeating it at least once. Claim 9 An atomic layer etching method according to claim 6, characterized in that the modification process is performed at a lower temperature than the etching process. Claim 10 An atomic layer etching method according to claim 9, characterized in that the etching process is performed at a temperature of 300°C or higher.

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