Substrate processing method and substrate processing apparatus

Abstract

A substrate processing method of the present invention uses a substrate processing apparatus comprising: a substrate support unit installed in a process chamber and including a susceptor plate capable of ascending and descending and rotating; and a gas spray unit provided above the substrate support unit and including a plurality of gas spray units including an inhibitor spray unit, a source gas spray unit, and a reaction gas spray unit to spray a plurality of process gases area-by-area. The substrate processing method is characterized by performing, at least once, the steps of: mounting a substrate on the substrate support unit and rotating same; supplying inhibitor gas to suppress the adsorption of a pyrolysis product of a source gas on the substrate; supplying the source gas to adsorb the source gas on the substrate; and supplying a reaction gas to form a thin film through a reaction with the source gas adsorbed on the substrate.

Description

Substrate processing method and substrate processing device

[0001] The present invention relates to semiconductor manufacturing, and more specifically, to a substrate processing method and substrate processing apparatus for manufacturing semiconductor devices.

[0002] Typically, to manufacture semiconductor devices, various processes are performed in a substrate processing device that includes a vacuum-atmosphere process chamber. For example, a substrate may be loaded into the process chamber, and processes such as depositing a thin film on the substrate or etching the thin film may be performed. Within the substrate processing device, the substrate is supported by a substrate support unit installed within the process chamber, and process gases are supplied to the substrate via a gas injection unit within the process chamber, allowing the substrate to be processed.

[0003] In some substrate processing systems, multiple substrates are mounted on a single substrate support and positioned within a process chamber. Process gases are then supplied to the substrates to form thin films on them. However, during the thin film formation process, the thin film quality deteriorates due to impurities or low crystallinity. Consequently, separate post-processing is performed after thin film formation. Therefore, there is a need to improve thin film quality during thin film formation without separate post-processing.

[0004] The present invention is intended to solve various problems including the above-mentioned problems, and aims to provide a substrate processing method and a substrate processing device capable of improving the quality of a thin film during a thin film formation process.

[0005] However, these tasks are exemplary and the scope of the present invention is not limited thereby.

[0006] According to an embodiment of the present invention for solving the above problem, a substrate processing method using a substrate processing apparatus including a process chamber having a processing space formed therein, a substrate support unit installed in the process chamber and having a susceptor plate that can be raised and lowered and rotated, and a gas injection unit provided on an upper portion of the substrate support unit and having a plurality of gas injection units including an inhibitor injection unit, a source gas injection unit, and a reaction gas injection unit for injecting a plurality of process gases into each region, the method comprising the steps of: placing a substrate on the substrate support unit and rotating it; supplying an inhibitor gas to suppress adsorption of a pyrolysis product of the source gas onto the substrate; supplying the source gas to adsorb the source gas onto the substrate; and supplying a reaction gas to form a thin film through a reaction with the source gas adsorbed onto the substrate; performing the steps at least once.

[0007] In the above substrate treatment method, the inhibitor may be a carbonate series compound.

[0008] In the above substrate treatment method, the inhibitor may be any one of DMC (dimethyl carbonate), EMC (ethyl methyl carbonate), DEC (diethyl carbonate), and MIC (methyl isopropyl carbonate).

[0009] In the above substrate processing method, the thin film may include a metal oxide film, the source gas may include a metal-containing gas, and the reaction gas may include an oxygen-containing gas.

[0010] In the above substrate processing method, the thin film may include an aluminum oxide film, the source gas may include trimethylaluminum (TMA) gas, and the oxygen-containing gas may include O3 gas or O2 gas.

[0011] In the above substrate processing method, the substrate support part may be installed on the susceptor plate and may have at least one satellite that can rotate the substrate by floating and rotating by the pressure of gas supplied through the susceptor plate, so that the substrate can be settled.

[0012] In the above substrate processing method, the reaction gas injection units are provided in a plurality of units spaced apart from each other, and when the thin film is formed, the substrate may be supplied with the reaction gas multiple times through the reaction gas injection units.

[0013] According to one embodiment of the present invention for solving the above problem, a substrate processing device includes: a process chamber having a processing space formed therein; a substrate support unit installed in the process chamber and having a susceptor plate that is capable of being raised and lowered and rotated; and a gas injection unit provided on an upper portion of the substrate support unit for injecting a plurality of process gases by region; wherein the gas injection unit includes: an inhibitor injection unit capable of supplying an inhibitor gas to suppress adsorption of a thermal decomposition product of a source gas onto the substrate mounted on the satellite; a source gas injection unit capable of supplying the source gas to adsorb the source gas onto the substrate; and a reaction gas unit capable of supplying a reaction gas to form a thin film through a reaction with the source gas adsorbed onto the substrate.

[0014] In the above substrate processing device, the inhibitor may be a carbonate series compound.

[0015] In the above substrate processing device, the thin film may include an aluminum oxide film, the source gas may include trimethylaluminum (TMA) gas, and the oxygen-containing gas may include O3 gas or O2 gas.

[0016] In the above substrate processing device, the substrate support unit may be installed on the susceptor plate and may have at least one satellite that can rotate the substrate by floating and rotating by the pressure of gas supplied through the susceptor plate, so that the substrate can be placed thereon.

[0017] In the above substrate processing device, the reaction gas injection units are provided in multiple units spaced apart from each other, and when forming the thin film, the substrate can receive the reaction gas multiple times through the reaction gas injection units.

[0018] According to the substrate processing method and substrate processing apparatus according to one embodiment of the present invention as described above, a substrate processing method and substrate processing apparatus capable of improving thin film quality during a thin film forming process can be implemented.

[0019] Of course, the scope of the present invention is not limited by these effects.

[0020] FIG. 1 is a cross-sectional view schematically showing a substrate processing device according to embodiments of the present invention.

[0021] Fig. 2 is a schematic exploded perspective view showing the substrate support part of the substrate processing device of Fig. 1.

[0022] Fig. 3 is a schematic bottom view showing an example of a gas injection unit in the substrate processing device of Fig. 1.

[0023] FIG. 4 is a drawing showing the process gas injection pattern of a unit cycle in a substrate processing method using a substrate processing device having a gas injection unit as shown in FIG. 3.

[0024] Fig. 5 is a schematic bottom view showing another example of a gas injection unit in the substrate processing device of Fig. 1.

[0025] FIG. 6 is a drawing showing the process gas injection pattern of a unit cycle in a substrate processing method using a substrate processing device having a gas injection unit as shown in FIG. 5.

[0026] FIG. 7 and FIG. 8 are graphs showing the characteristics of an aluminum oxide film according to the temperature of the substrate when forming a thin film using a substrate processing device according to embodiments of the present invention.

[0027] Figure 9 is an XRD (X-ray Diffraction) result for evaluating the effect of an inhibitor gas on the crystallinity of an aluminum oxide film in a substrate processing method according to an experimental example of the present invention.

[0028] Figure 10 is a graph showing the effect of an inhibitor gas on the grain size of an aluminum oxide film in a substrate processing method according to an experimental example of the present invention.

[0029] Figure 11 is a graph showing the effect of an inhibitor gas on the electrical characteristics (k-value) of an aluminum oxide film in a substrate processing method according to an experimental example of the present invention.

[0030] Hereinafter, various preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0031] The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. The following embodiments may be modified in various ways, and the scope of the present invention is not limited to the following embodiments. Rather, these embodiments are provided to more faithfully and completely explain the present disclosure and to fully convey the spirit of the present invention to those skilled in the art. In addition, the thickness and size of each layer in the drawings are exaggerated for convenience and clarity of explanation.

[0032] FIG. 1 is a cross-sectional view schematically showing a substrate processing device (200) according to one embodiment of the present invention, FIG. 2 is a schematic exploded perspective view showing a substrate support part of the substrate processing device (200) of FIG. 1, and FIG. 3 is a schematic bottom view showing an example of a gas injection part in the substrate processing device (200) of FIG. 1.

[0033] Referring to FIGS. 1 to 3, the substrate processing device (200) may include a process chamber (210), a gas injection unit (220), and a substrate support unit (230).

[0034] The process chamber (210) may include a processing space (212) for processing substrates (S) therein. The process chamber (210) may be provided in various shapes, and may include, for example, a chamber body (213) having an open upper portion and a chamber lid (214) coupled to the chamber body (213). Furthermore, a sealing member for vacuum sealing, such as an O-ring, may be coupled between the chamber body (213) and the chamber lid (214). Furthermore, an openable gate (not shown) may be installed on a side wall of the chamber body (213) to allow movement of the substrates (S).

[0035] The process chamber (210) is configured to maintain airtightness, and can be connected to a vacuum pump (not shown) through at least one exhaust line (216) to discharge process gas within the process space (212) and control the vacuum level within the process space (212). For example, a throttle valve is installed in the exhaust line (216), and the vacuum level within the process chamber (210) can be controlled by controlling the opening rate of the throttle valve. In some embodiments, two exhaust lines (216) may be connected to different locations within the process chamber (210).

[0036] The substrate support unit (230) can be installed in the process chamber (210) facing the gas injection unit (220) to support the substrate (S).

[0037] The substrate support unit (230) may be equipped with a susceptor plate (110). Specifically, the substrate support unit (230) may be installed within the process chamber (210) and may be equipped with a susceptor plate (110) that can be raised, lowered, and rotated. The substrate (S) may be rotated by the rotation of the susceptor plate (110).

[0038] Furthermore, the substrate support member (230) may be provided with at least one satellite (130). Specifically, the substrate support member (230) may be installed on a susceptor plate (110) and may have at least one satellite (130) on which a substrate (S) may be mounted and which may float and rotate by the pressure of gas supplied through the susceptor plate (110) to rotate the substrate (S).

[0039] The susceptor plate (110) may include at least one substrate mounting portion (120) on which a substrate (S) is mounted. For example, the substrate mounting portion (120) may be provided in a pocket-shaped shape on the susceptor plate (110). In order to process multiple substrates (S) at once, the substrate mounting portions (120) may be provided in plurality. For example, a plurality of substrate mounting portions (120) may be formed on the upper surface of the susceptor plate (110) at a predetermined distance apart from each other in the circumferential direction. More specifically, the substrate mounting portions (120) may be radially arranged equiangularly around the rotational axis of the susceptor plate (110).

[0040] A plurality of gas flow lines (112, 116) connected to a substrate mounting portion (120) may be formed on the susceptor plate (110). For example, a predetermined working gas, such as a floating gas for floating the substrate (S), a rotation gas for rotating the substrate (S), and / or a deceleration gas for slowing or stopping the rotation of the substrate (S), may be supplied to the substrate mounting portion (120) through the gas flow lines (112, 116). The floating gas, the rotation gas, and the deceleration gas may be separated from each other through the gas flow lines (112, 116) and supplied to the satellite (130) through the substrate mounting portion (120).

[0041] At least one satellite (130) may be placed on the substrate mounting portion (120). A substrate (S) may be placed on the upper surface of the satellite (130). For example, a plurality of satellites (130) may be placed on each of a plurality of substrate mounting portions (120), and in this case, the number of satellites (130) may be the same as the number of substrate mounting portions (120). The number of substrate mounting portions (120) illustrated in FIG. 2 is exemplary and the technical idea of ​​the present invention is not limited thereto.

[0042] The satellite (130) can be supplied with a floating gas from the substrate mounting portion (120) and can be floated from the substrate mounting portion (120). Furthermore, the satellite (130) can be rotated relative to the susceptor plate (110) by the rotational gas supplied in the forward rotational direction from the substrate mounting portion (120), thereby rotating the substrate (S) relative to the susceptor plate (110). Since this rotation is a relative rotation with respect to the susceptor plate (110), it can be called a rotation. Furthermore, the satellite (130) can be braked by the decelerating gas supplied in the reverse rotational direction from the substrate mounting portion (120).

[0043] For example, the forward rotation direction may refer to the direction in which the satellite (130) rotates, and the reverse rotation direction may refer to the opposite direction of the forward rotation direction so as to reduce the rotating satellite (130). More specifically, the forward rotation direction and the reverse rotation direction may be opposite directions along the tangent line of the circumference depending on the position of the satellite (130).

[0044] Additionally, a shaft (160) may be coupled to the susceptor plate (110). The shaft (160) may be rotatable so that the substrate (S) may rotate. For example, a driving device (not shown) may be coupled to the shaft (160), and the shaft (160) may be rotated or moved up and down by the driving device. As the shaft (160) rotates or moves up and down, the susceptor plate (110) may also rotate or move up and down.

[0045] A plurality of gas supply lines (162, 164, 166) through which floating gas, rotating gas, and decelerating gas move may be formed inside the shaft (160). For example, the gas supply lines (162, 164, 166) may include a first gas supply line (162) for supplying floating gas, a second gas supply line (166) for supplying decelerating gas, and a rotating gas flow line (164) for supplying rotating gas.

[0046] The substrate support member (230) can be coupled to the process chamber (210) using a bellows structure (not shown) so that the sealing of the process chamber (210) can be maintained when the shaft (160) is raised and / or rotated.

[0047] In some embodiments, a heater unit (not shown) may be installed under the susceptor plate (110) within the process chamber (210) to heat the substrates (S) mounted on the susceptor plate (110). In other embodiments, a heater unit (not shown) may be built into and installed within the susceptor plate (110). The heater unit may include at least one heater, and the heater may include various heating sources such as a heating wire or a cartridge heater.

[0048] The gas injection unit (220) may be installed at the top of the process chamber (210) facing the substrate support unit (230) to inject a plurality of process gases into the process space (212) by region. For example, the gas injection unit (220) may inject process gases supplied from the outside of the process chamber (210) into the process space (212). More specifically, the gas injection unit (220) may be installed at the top of the process chamber (210), for example, the chamber lid (214), to inject process gases onto a substrate (S) mounted on the substrate support unit (230).

[0049] The gas injection unit (220) may include an inhibitor injection unit (221) for injecting an inhibitor gas, a source gas injection unit (224) for injecting a source gas, and a reaction gas injection unit (226) for injecting a reaction gas. When the susceptor plate (110) constituting the substrate support unit (230) rotates, the substrates (S) may be sequentially supplied with the inhibitor gas, the source gas, and the reaction gas.

[0050] When the substrate processing method using the substrate processing device (200) is a thin film forming method, for example, the thin film may include a metal oxide film (e.g., an aluminum oxide film), the inhibitor may include a carbonate series compound (e.g., any one of dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and methyl isopropyl carbonate (MIC)), the source gas may include a metal-containing gas (e.g., trimethylaluminum (TMA) gas), and the reaction gas may include an oxygen-containing gas (e.g., O3 gas or O2 gas).

[0051] Furthermore, the gas injection unit (220) may further include a purge gas injection unit (228) for injecting purge gas between the inhibitor injection unit (221), the source gas injection unit (224), and the reaction gas injection unit (226). For example, the purge gas may include an inert gas, such as Ar gas or N2 gas.

[0052] Optionally, the gas injection unit (220) may further include a curtain gas injection unit (222) installed at its center. The curtain gas injection unit (222) may be provided with injection holes for injecting curtain gas to prevent mixing of process gases, for example, mixing of an inhibitor gas, a source gas, and a reaction gas. For example, the curtain gas may include an inert gas.

[0053] Hereinafter, a substrate processing method using the aforementioned substrate processing device (200), for example, a thin film forming method, will be described with reference to FIGS. 1 to 4.

[0054] First, substrates (S) can be mounted on satellites (130) arranged on mounting grooves (120) on a susceptor plate (110). For example, the substrates (S) can be sequentially loaded onto the susceptor plate (110) while rotating the substrate support member (230).

[0055] Next, the substrates (S) can be rotated by being floated and rotated by the pressure of the floating gas and the rotating gas supplied through the susceptor plate (110). Meanwhile, while the process gases are being sprayed from the gas spray unit (220), the shaft (160) can be rotated to rotate the susceptor plate (110) constituting the substrate support unit (230). In this case, although the process gases are continuously sprayed from the gas spray unit (220), different process gases can be sequentially supplied onto the substrates (S) as the susceptor plate (110) rotates.

[0056] Therefore, a thin film can be formed on substrates (S) by performing space-division atomic layer deposition using a substrate processing device (100). For example, the susceptor plate (110) can be continuously rotated. In this case, each substrate (S) can be sequentially moved under the inhibitor injection unit (221), the source gas injection unit (224), and the reaction gas injection unit (226) at each rotation. In addition, each substrate (S) can be moved under the purge gas injection unit (228; 228a, 228b, 228c) arranged between the inhibitor injection unit (221), the source gas injection unit (224), and the reaction gas injection unit (226) at each rotation.

[0057] That is, the substrates (S) may be supplied with an inhibitor gas under an inhibitor injection unit (221), then supplied with a source gas under a source gas injection unit (224), and then supplied with a reaction gas from a reaction gas injection unit (226), and this cycle may be performed at least once. The inhibitor gas is supplied to suppress adsorption of thermal decomposition products of the source gas on the substrates. At least a portion of the source gas is adsorbed on the substrates, and the source gas adsorbed on the substrates reacts with the reaction gas to form a thin film.

[0058] The above cycle, which is performed at least once while the substrate (S) is placed on the substrate support member (230) and rotated, includes, with reference to FIG. 4, a step of supplying an inhibitor gas (IHB) to suppress adsorption of a thermal decomposition product of the source gas onto the substrate (S); a step of supplying a source gas (Src) to adsorb the source gas onto the substrate (S); and a step of supplying a reaction gas (O3) to form a thin film through a reaction with the source gas adsorbed onto the substrate (S). In addition, by supplying a purge gas (N2 / Ar) onto the substrate (S) between each step in the above cycle, the unadsorbed or remaining inhibitor gas (IHB), source gas (Src), and reaction gas (O3) can be purged.

[0059] Depending on the thin film to be formed and the source gas, the temperature of the substrate support portion may be maintained between 300 and 700°C during the formation of the thin film. Furthermore, for example, the temperature of the substrate support portion may be maintained at 500°C or higher during the formation of the thin film.

[0060] If the thin film to be formed is a metal oxide film, for example, an aluminum oxide film, the source gas may be an aluminum precursor, for example, trimethylaluminum (TMA) gas.

[0061] When the process temperature for forming an aluminum oxide film using trimethylaluminum (TMA) gas as a source gas is 25℃ or higher and less than 500℃, photodecomposition occurs in which trimethylaluminum (TMA) decomposes and methyl is dropped, and the crystallinity of the aluminum oxide film is poor, making it difficult to secure electrical properties. In this case, an additional process is required to improve the crystallinity of the aluminum oxide film by heat treatment at a high temperature (e.g., 800℃) after forming the aluminum oxide film. However, the thermal budget of high temperatures can have a negative impact on semiconductor devices.

[0062] Meanwhile, when the process temperature for forming an aluminum oxide film using trimethylaluminum (TMA) gas as a source gas is 500℃ or higher, the thermal decomposition of trimethylaluminum (TMA) progresses as the process temperature gradually increases. The main thermal decomposition products of trimethylaluminum (TMA) include dimethyl aluminum (DMA), monomethyl aluminum (MMA), CH3 substances, as well as products such as C2H4 and C-Al-C-Al-C. When performing the ALD process for depositing an AlxOy thin film at a temperature (>500℃) where thermal decomposition occurs in this way, it is difficult to obtain the characteristics of the ALD process. For example, when depositing an aluminum oxide film (AlxOy) on a pattern having a step structure, the thermal decomposition products of trimethylaluminum (TMA) are adsorbed at the entrance of the step structure, causing an overhang phenomenon, which deteriorates the step coverage. In addition, if the thermal decomposition product components generated in a high-temperature region of 500℃ or higher remain in the aluminum oxide film, the film quality of the aluminum oxide film deteriorates and the electrical characteristics deteriorate.

[0063] In the present invention, a technical idea is proposed in which, when a process temperature for forming an aluminum oxide film using trimethylaluminum (TMA) gas as a source gas is in the range of 500°C or higher, a carbonate series compound is provided as an inhibitor gas on a substrate before the source gas is adsorbed on the substrate, thereby effectively suppressing the adsorption of thermal decomposition products of the source gas on the substrate, thereby improving the step coverage of a step structure, and improving the crystallinity of the aluminum oxide film and the electrical characteristics (k-value) without performing additional high-temperature heat treatment. The inhibitor is a carbonate series compound, and may be, for example, any one of dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and methyl isopropyl carbonate (MIC).

[0064] For example, when the inhibitor gas is dimethyl carbonate (DMC), the inhibitor gas combines with aluminum to suppress the adsorption of products of the thermal decomposition of trimethyl aluminum (TMA), thereby maintaining a self-limiting reaction, and thus the ALD characteristics can be maintained even at the temperature at which trimethyl aluminum (TMA) is thermally decomposed. In addition, the inhibitor gas generates steric hinderance, allowing trimethyl aluminum (TMA) to be consistently adsorbed at the O site, which can induce crystalline growth of the aluminum oxide film.

[0065] Below, another example of a gas injection unit in the substrate processing device of Fig. 1 is described, and a substrate processing method according to the gas injection unit is described.

[0066] Referring to FIGS. 1, 2, and 5, the substrate processing device (200) may include a process chamber (210), a gas injection unit (220), and a substrate support unit (230). Unlike the gas injection unit illustrated in FIG. 3, the gas injection unit (220) illustrated in FIG. 5 has a plurality of reaction gas injection units (226) spaced apart from each other. Descriptions of the process chamber (210) and the substrate support unit (230) are the same as those described above, and thus are omitted.

[0067] The gas injection unit (220) may include an inhibitor injection unit (221) for injecting an inhibitor gas, a source gas injection unit (224) for injecting a source gas, and a reaction gas injection unit (226) for injecting a reaction gas. When the susceptor plate (110) constituting the substrate support unit (230) rotates, the substrates (S) may be sequentially supplied with the inhibitor gas, the source gas, and the reaction gas.

[0068] When the substrate processing method using the substrate processing device (200) is a thin film forming method, for example, the thin film may include a metal oxide film (e.g., an aluminum oxide film), the inhibitor may include a carbonate series compound (e.g., any one of dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and methyl isopropyl carbonate (MIC)), the source gas may include a metal-containing gas (e.g., trimethylaluminum (TMA) gas), and the reaction gas may include an oxygen-containing gas (e.g., O3 gas or O2 gas).

[0069] As another example, the metal oxide film may include hafnium oxide (Hf oxide), zirconium oxide (Zr oxide), lanthanum oxide (La oxide), and yttrium oxide (Y oxide).

[0070] A reaction gas injection unit (226) for injecting a reaction gas includes a first reaction gas injection unit (226a) and a second reaction gas injection unit (226b). A cycle of supplying a first reaction gas from the first reaction gas injection unit (226a) and then supplying a second reaction gas from the second reaction gas injection unit (226b) can be repeatedly performed multiple times. In the above cycle, the substrates (S) can be supplied with a purge gas between each step.

[0071] In each cycle, a metal-containing gas is adsorbed on the substrates (S), and then a first reaction gas reacts with the metal-containing gas to form a metal oxide film on the substrates (S) in atomic layers, and a second reaction gas can improve the quality of the metal oxide film. For example, the second reaction gas can perform functions such as metal oxidation, metal ligand removal, surface impurity removal of the metal oxide film, and improvement of the crystallinity of the metal oxide film. Therefore, by using the substrate processing device (200) described above, by arranging a plurality of reaction gas injection units (226), the quality of the metal oxide film can be improved along with the formation of the metal oxide film. For example, the crystallinity of the metal oxide film can be improved, and the impurity content in the metal oxide film can be reduced, so that the dielectric constant of the metal oxide film can be increased.

[0072] Furthermore, the gas injection unit (220) may further include a purge gas injection unit (228) for injecting purge gas between the inhibitor injection unit (221), the source gas injection unit (224), and the reaction gas injection unit (226). For example, the purge gas may include an inert gas, such as Ar gas or N2 gas.

[0073] A substrate processing method using the aforementioned substrate processing device (200), for example, a thin film forming method, is described with reference to FIGS. 1, 2, 5, and 6.

[0074] First, substrates (S) can be mounted on satellites (130) arranged on mounting grooves (120) on a susceptor plate (110). For example, the substrates (S) can be sequentially loaded onto the susceptor plate (110) while rotating the substrate support member (230).

[0075] Next, the substrates (S) can be rotated by being floated and rotated by the pressure of the floating gas and the rotating gas supplied through the susceptor plate (110). Meanwhile, while the process gases are being sprayed from the gas spray unit (220), the shaft (160) can be rotated to rotate the susceptor plate (110) constituting the substrate support unit (230). In this case, although the process gases are continuously sprayed from the gas spray unit (220), different process gases can be sequentially supplied onto the substrates (S) as the susceptor plate (110) rotates.

[0076] Therefore, a thin film can be formed on substrates (S) by performing space-division atomic layer deposition using a substrate processing device (100). For example, the susceptor plate (110) can be continuously rotated. In this case, each substrate (S) can be sequentially moved under the inhibitor injection unit (221), the source gas injection unit (224), the first reaction gas injection unit (226a), and the second reaction gas injection unit (226b) at each rotation.

[0077] In addition, each substrate (S) can be moved under a purge gas injection unit (228; 228a, 228b, 228c, 228d) disposed between the inhibitor injection unit (221), the source gas injection unit (224), the first reaction gas injection unit (226a), and the second reaction gas injection unit (226b) at each rotation. The purge gas injection unit (228) is an injection unit for injecting a purge gas, and for example, the purge gas can include an inert gas, such as Ar gas or N2 gas. For example, N2 gas can be injected through the purge gas injection units (228a, 228d), and Ar gas can be injected through the purge gas injection units (228b, 228c).

[0078] Meanwhile, in FIG. 5, a configuration is illustrated in which a purge gas injection unit is not arranged between the second reaction gas injection unit (226b) and the inhibitor injection unit (221), but in another modified embodiment, a purge gas injection unit may be arranged between the second reaction gas injection unit (226b) and the inhibitor injection unit (221).

[0079] That is, the substrates (S) are supplied with an inhibitor gas under the inhibitor injection unit (221), then the source gas is supplied under the source gas injection unit (224), then the first reaction gas is supplied from the first reaction gas injection unit (226a), and then the second reaction gas is supplied from the second reaction gas injection unit (226b). This cycle can be performed at least once. The inhibitor gas is supplied to suppress the adsorption of thermal decomposition products of the source gas on the substrates. At least a portion of the source gas is adsorbed on the substrates, and the source gas adsorbed on the substrates reacts with the first reaction gas to form a thin film. The second reaction gas injected from the second reaction gas injection unit (226b) can contribute to the formation of a thin film to some extent, but can mainly be used for post-processing to improve the thin film quality.

[0080] The above cycle, which is performed at least once while the substrate (S) is placed on the substrate support member (230) and rotated, includes, with reference to FIG. 6, a step of supplying an inhibitor gas (IHB) to suppress adsorption of a thermal decomposition product of the source gas onto the substrate (S); a step of supplying a source gas (Src) to adsorb the source gas onto the substrate (S); a step of supplying a first reaction gas (O3) to form a thin film through a reaction with the source gas adsorbed onto the substrate (S); and a step of supplying a second reaction gas (O3) to perform a film quality post-treatment of the thin film. In addition, by supplying a purge gas (N2 / Ar) onto the substrate (S) between each step in the above cycle, the unadsorbed or remaining inhibitor gas (IHB), the source gas (Src), the first reaction gas (O3), and the second reaction gas (O3) can be purged.

[0081] If the thin film to be formed is a metal oxide film, for example, an aluminum oxide film, the source gas may be an aluminum precursor, for example, trimethylaluminum (TMA) gas.

[0082] As described above, in the present invention, when the process temperature for forming an aluminum oxide film using trimethylaluminum (TMA) gas as a source gas is in the range of 500°C or higher, by providing a carbonate series compound as an inhibitor gas on the substrate before the source gas is adsorbed on the substrate, the adsorption of the thermal decomposition product of the source gas on the substrate can be effectively suppressed, thereby improving the step coverage of the step structure, and the crystallinity of the aluminum oxide film can be improved without performing an additional high-temperature heat treatment, and the electrical characteristics (k-value) can be improved. Furthermore, by providing a plurality of reaction gas injection units (226) spaced apart from each other, the crystallinity of the metal oxide film can be increased, and the concentration of carbon impurities can be lowered, thereby lowering the dielectric constant value.

[0083] Below, the effect of deposition temperature on the quality of a thin film, such as a metal oxide film, such as aluminum oxide (AlO), when forming a thin film using atomic layer deposition is described.

[0084] Figures 7 and 8 are graphs showing the characteristics of an aluminum oxide film (AlO) according to the temperature of the substrate when forming a thin film using a substrate processing device.

[0085] Referring to Fig. 7, it can be seen that when the deposition temperature, i.e., the temperature of the substrate (S), increases when forming an aluminum oxide (AlO) film using atomic layer deposition, the critical thickness for crystallinity decreases. It is known that when forming an aluminum oxide (AlO) film using atomic layer deposition, the aluminum oxide (AlO) film becomes crystalline only when the critical thickness is greater than or equal to the critical thickness. However, it can be seen that the critical thickness for this crystallinity decreases as the temperature of the substrate (S) increases. Therefore, it can be seen that when the target thickness is very low when forming an aluminum oxide (AlO) film, the control temperature during atomic layer deposition must be increased to secure crystallinity.

[0086] Referring to Fig. 8, it can be seen that when an aluminum oxide film (AlO) is formed using atomic layer deposition, as the temperature of the substrate (S) increases, the concentration of carbon impurities in the aluminum oxide film (AlO) increases. These carbon impurities can deteriorate the quality of the aluminum oxide film (AlO), and for example, the dielectric constant value (k value) can decrease. This result is interpreted as being because as the temperature of the substrate (S) increases, the thermal decomposition of the TMA gas used as the source gas becomes more active, resulting in the generation of carbon and its inclusion in the thin film.

[0087] Therefore, when forming an aluminum oxide film (AlO) using atomic layer deposition, if the temperature of the substrate (S), i.e., the deposition temperature, is increased, the critical thickness having crystallinity can be lowered, but the problem of increasing the content of carbon impurities in the thin film arises. In this respect, it can be seen that in order to obtain a high-quality aluminum oxide film (AlO) having low crystallinity, an additional process of removing carbon impurities while increasing the temperature of the substrate (S) during atomic layer deposition is necessary. For example, the substrate processing apparatus (200) according to embodiments of the present invention can maintain the temperature of the substrate support (230) at 500°C or higher in order to increase the crystallinity and dielectric constant of the metal oxide film. In some embodiments, the temperature of the substrate support (230) can be maintained at 620°C.

[0088] As described above, according to the substrate processing device (200) according to embodiments of the present invention, when forming a metal oxide film, for example, an aluminum oxide film (AlO), the temperature of the substrate support member (230) is controlled, and an inhibitor gas, which is a carbonate series compound, is supplied to suppress adsorption of thermal decomposition products of the source gas, thereby obtaining a high-quality aluminum oxide film (AlO) having crystallinity.

[0089] The effect of supplying an inhibitor gas, which is a carbonate series compound, on the step coverage, crystallinity and electrical characteristics (k-value) of the aluminum oxide film is described.

[0090] Table 1 compares the coating rates of aluminum oxide films according to experimental examples of the present invention. In this experimental example, the coating rates were evaluated in a pattern having a step structure. The step structure is a pattern structure having an inlet diameter of approximately 0.149 μm, a depth of approximately 4.18 μm, and an aspect ratio of approximately 28.

[0091] Experimental Example 1 Experimental Example 2 Experimental Example 3 Application Rate (%) 94.4 1 2 2.6 9 9.7

[0092] Experimental Example 1 corresponds to the case where an inhibitor gas is not provided in the substrate processing method illustrated in Fig. 6, and Experimental Examples 2 and 3 correspond to the case where an inhibitor gas is provided in the substrate processing method illustrated in Fig. 6. Experimental Example 2 corresponds to the case where the supply flow rate of the inhibitor gas is 2 sccm, and Experimental Example 3 corresponds to the case where the supply flow rate of the inhibitor gas is 6 sccm. In Experimental Examples 1, 2, and 3, the temperature of the substrate support part was applied at the same condition of 600°C during the process of forming an aluminum oxide film.

[0093] Referring to Table 1, it can be confirmed that the coating rate of the aluminum oxide film is improved in cases where an inhibitor gas is provided (Experimental Examples 2 and 3) compared to when an inhibitor gas is not provided (Experimental Example 1). It can be confirmed that the inhibitor gas is effective in improving the coating rate because it suppresses the adsorption of thermal decomposition products of the source gas on the substrate, thereby suppressing the occurrence of overhang at the entrance of the step structure.

[0094] In addition, in Experimental Example 2 compared to Experimental Example 3, the diffusion of the inhibitor gas does not proceed to the lower part of the step structure but stops at the relatively upper part of the step structure, so the aluminum oxide film is formed relatively thicker at the lower part of the step structure compared to Experimental Example 3, resulting in a high coating rate. According to these results, it can be understood that the coating rate and coating profile of the aluminum oxide film formed on the step structure can be controlled by adjusting the flow rate of the inhibitor gas.

[0095] Fig. 9 is an XRD (X-ray Diffraction) result for evaluating the effect of an inhibitor gas on the crystallinity of an aluminum oxide film in a substrate processing method according to an experimental example of the present invention. Fig. 10 is a graph showing the effect of an inhibitor gas on the grain size of an aluminum oxide film in a substrate processing method according to an experimental example of the present invention.

[0096] Table 2 is a table that summarizes the results of FIGS. 9 and 10. In Experimental Examples 4 and 5, the process temperature for forming an aluminum oxide film is 650°C, and in Experimental Examples 6 and 7, the process temperature for forming an aluminum oxide film is 600°C. In addition, Experimental Examples 4 and 6 correspond to the case where an inhibitor gas is not provided in the substrate processing method illustrated in FIG. 6 in Experimental Example 1, and Experimental Examples 5 and 7 correspond to the case where an inhibitor gas is provided in the substrate processing method illustrated in FIG. 6.

[0097] No. Condition Process Temperature (℃) FWHM Grain Size (nm) Experimental Example 4 TMA 650℃ 1.73 5.75 Experimental Example 5 TMA + IHB 650℃ 1.59 6.28 Experimental Example 6 TMA 600℃ 2.33 4.28 Experimental Example 7 TMA + IHB 600℃ 2.05 4.85

[0098] Referring to FIG. 9, FIG. 10 and Table 2, it can be confirmed that when an inhibitor gas is supplied in a substrate processing method for forming an aluminum oxide film, the crystallinity of the aluminum oxide film is improved.

[0099] Fig. 11 is a graph showing the effect of an inhibitor gas on the electrical characteristics (k-value) of an aluminum oxide film in a substrate processing method according to an experimental example of the present invention. In Fig. 11, the TMA+O3 item on the left corresponds to the case where an inhibitor gas is not provided in the substrate processing method illustrated in Fig. 6, and the IHB+TMA+O3 item on the right corresponds to the case where an inhibitor gas is provided in the substrate processing method illustrated in Fig. 6.

[0100] Referring to Fig. 11, it can be confirmed that when an inhibitor gas is supplied as shown in Fig. 6, the crystallinity and electrical characteristics (k-value) are improved.

[0101] While the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary, and those skilled in the art will appreciate that various modifications and equivalent alternative embodiments are possible. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the appended claims.

Claims

1. A substrate processing method using a substrate processing device including a process chamber in which a processing space is formed, a substrate support section having a susceptor plate installed in the process chamber and capable of being raised and lowered and rotated, and a gas injection section provided on the upper portion of the substrate support section and having a plurality of gas injection units including an inhibitor injection unit, a source gas injection unit, and a reaction gas injection unit for injecting a plurality of process gases by region, A step of placing the substrate on the substrate support and rotating it; A step of supplying an inhibitor gas to suppress adsorption of thermal decomposition products of the source gas on the substrate; A step of supplying a source gas to adsorb the source gas on the substrate; and A step of supplying a reaction gas to form a thin film through a reaction with a source gas adsorbed on the substrate; characterized in that the step is performed at least once. Substrate processing method.

2. In paragraph 1, The above inhibitor is characterized in that it is a carbonate series compound. Substrate processing method.

3. In paragraph 2, The inhibitor is characterized in that it is one of DMC (dimethyl carbonate), EMC (ethyl methyl carbonate), DEC (diethyl carbonate) and MIC (methyl isopropyl carbonate). Substrate processing method.

4. In paragraph 2, The above thin film includes a metal oxide film, The above source gas contains a metal-containing gas, The above reaction gas contains oxygen-containing gas, Substrate processing method.

5. In paragraph 4, The above thin film includes an aluminum oxide film, The above source gas contains trimethylaluminum (TMA) gas, The above oxygen-containing gas includes O3 gas or O2 gas. Substrate processing method.

6. In paragraph 1, The substrate support portion is installed on the susceptor plate and has at least one satellite on which the substrate can be placed and which can rotate the substrate by floating and rotating by the pressure of the gas supplied through the susceptor plate. Substrate processing method.

7. In paragraph 1, The above reaction gas injection units are provided in multiple units spaced apart from each other, The substrate is characterized in that, when forming the above thin film, the reaction gas is supplied multiple times through the reaction gas injection unit. Substrate processing method.

8. Process chamber with processing space formed; A substrate support unit installed within the process chamber and having a susceptor plate that can be raised, lowered, and rotated; It includes a gas injection unit provided on the upper part of the substrate support unit for injecting a plurality of process gases into each area; The above gas injection unit, An inhibitor injection unit capable of supplying an inhibitor gas to suppress adsorption of thermal decomposition products of the source gas on the substrate mounted on the satellite; A source gas injection unit capable of supplying a source gas to adsorb the source gas on the substrate; and A reaction gas unit capable of supplying a reaction gas to form a thin film through a reaction with a source gas adsorbed on the substrate; Substrate processing equipment.

9. In paragraph 8, The above inhibitor is characterized in that it is a carbonate series compound. Substrate processing equipment.

10. In paragraph 9, The above thin film includes an aluminum oxide film, The above source gas contains trimethylaluminum (TMA) gas, The above oxygen-containing gas includes O3 gas or O2 gas. Substrate processing equipment.

11. In paragraph 8, The substrate support portion is installed on the susceptor plate and has at least one satellite on which the substrate can be placed and which can rotate the substrate by floating and rotating by the pressure of the gas supplied through the susceptor plate. Substrate processing equipment.

12. In paragraph 8, The above reaction gas injection units are provided in multiple units spaced apart from each other, The substrate is characterized in that, when forming the above thin film, the reaction gas is supplied multiple times through the reaction gas injection unit. Substrate processing equipment.

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