Method for forming a silicon insulating film

Abstract

The present invention relates to a method for forming a silicon insulating film, and more particularly to a method for forming an oxygen-doped silicon insulating film on a substrate. A method for forming a silicon insulating film according to an embodiment of the present invention is a method for forming an oxygen-doped silicon insulating film, comprising the steps of: providing a substrate in a reaction space; forming a silicon insulating film on the substrate using an atomic layer deposition process; and forming a plasma in the reaction space using an oxygen-containing gas in order to dope the silicon insulating film with oxygen.

Description

Technical Field

[0001] The present invention relates to a method for forming a silicon insulating film, and more particularly, to a method for forming a silicon insulating film for forming a silicon insulating film doped with oxygen on a substrate.

Background Art

[0002] As a technique for depositing a thin film on a substrate, an atomic layer deposition (ALD) method is known in which a process of depositing the thin film in atomic layer units is repeated until a desired film thickness is reached. The atomic layer deposition method can deposit a thin film having excellent step coverage and a high film density compared to the conventional chemical vapor deposition (CVD) method.

[0003] On the other hand, a silicon insulating film doped with oxygen is a dielectric widely used in the manufacture of semiconductor devices, and is mainly used as an interlayer dielectric (ILD) of a transistor such as a spacer of a gate electrode.

[0004] When such a silicon insulating film is deposited by the atomic layer deposition method, hydrogen contained in the source gas containing silicon is inevitably contained in the silicon insulating film. That is, the silicon insulating film formed by the atomic layer deposition method has excellent step coverage and a high film density, but has a relatively high hydrogen content compared to thin films formed by other deposition methods. For this reason, conventionally, after forming a silicon insulating film with a desired film thickness on a substrate, a treatment process for removing hydrogen contained in the silicon insulating film has been performed. However, in this case, the region where hydrogen is removed is limited to the surface of the thin film, and as a result, there is a problem that it is difficult to effectively remove hydrogen contained inside the thin film.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Korean Published Patent Publication No. 10-2013-0118963 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The present invention provides a method for forming a silicon insulating film that can form an oxygen-doped silicon insulating film while controlling the hydrogen content. [Means for solving the problem]

[0007] A method for forming a silicon insulating film according to an embodiment of the present invention is a method for forming an oxygen-doped silicon insulating film, comprising the steps of: providing a substrate in a reaction space; forming a silicon insulating film on the substrate using an atomic layer deposition process; and forming a plasma in the reaction space using an oxygen-containing gas in order to dope the silicon insulating film with oxygen.

[0008] At least one of the steps of forming the silicon insulating film and forming the plasma may be performed multiple times.

[0009] The step of forming the silicon insulating film may be performed after the step of forming the plasma.

[0010] The step of forming the plasma may include supplying a gas consisting of one or more of the following gases into the reaction space: nitrous oxide (N2O), ozone (O3), water (H2O), ammonia (NH3), nitrogen (N2), oxygen (O2), and argon (Ar).

[0011] The step of forming the silicon insulating film may include the step of supplying a source gas containing TSA (trisilylamine) and the step of supplying a reactant gas containing nitrogen.

[0012] The step of forming the plasma may include the steps of isolating a storage space for storing an oxygen-containing gas from the reaction space, filling the storage space with the oxygen-containing gas, and connecting the storage space to the reaction space and supplying the oxygen-containing gas to the reaction space.

[0013] In the step of supplying the oxygen-containing gas, the supply line connecting the storage space and the reaction space may be opened to its maximum extent at once to supply the oxygen-containing gas.

[0014] The temperature of the substrate or the reaction space may be maintained at a temperature of 100 to 400°C.

[0015] Furthermore, an embodiment of the present invention provides a method for forming a silicon insulating film, comprising the steps of: providing a substrate in a reaction space; supplying a silicon-containing gas and a nitrogen-containing gas onto the substrate and forming a silicon insulating film by a chemical vapor deposition process; and forming a plasma using an oxygen-containing gas in the reaction space in order to dope the silicon insulating film with oxygen.

[0016] At least one of the steps of forming the silicon insulating film and forming the plasma may be performed multiple times.

[0017] The step of forming the silicon insulating film may be performed after the step of forming the plasma.

[0018] The step of forming the plasma may include supplying a gas consisting of one or more of the following gases into the reaction space: nitrous oxide (N2O), ozone (O3), water (H2O), ammonia (NH3), nitrogen (N2), oxygen (O2), and argon (Ar).

[0019] The aforementioned silicon-containing gas may also be TSA (trisilylamine).

[0020] The step of forming the plasma may include a step of blocking a storage space storing a gas containing oxygen from the reaction space, a step of fully filling the storage space with the gas containing oxygen, and a step of communicating the storage space with the reaction space to supply the gas containing oxygen to the reaction space.

[0021] In the step of supplying the gas containing oxygen, the supply line connecting the storage space and the reaction space may be opened to the maximum extent at one time to supply the gas containing oxygen.

[0022] The temperature of the substrate or the reaction space may be maintained at a temperature of 100 to 400°C.

Advantages of the Invention

[0023] According to an embodiment of the present invention, by performing plasma treatment by exposing a silicon insulating film to plasma formed using a gas containing oxygen, oxygen can be doped into the silicon insulating film, and hydrogen contained inside the silicon insulating film can be removed in atomic layer units.

[0024] Also, by selectively performing plasma treatment, the content of hydrogen in the silicon insulating film doped with oxygen can be effectively controlled, and the components of the silicon insulating film that change with the plasma treatment can also be effectively controlled.

Brief Description of the Drawings

[0025] [Figure 1] A diagram schematically showing a substrate processing apparatus according to an embodiment of the present invention. [Figure 2] A diagram schematically showing a method for forming a silicon insulating film according to an embodiment of the present invention. [Figure 3] A diagram schematically showing a method for forming a silicon insulating film according to another embodiment of the present invention.

Modes for Carrying Out the Invention

[0026] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. However, the present invention is not limited in any way to the embodiments disclosed below and can be embodied in a variety of different forms, and the following embodiments are provided merely to complete the disclosure of the present invention and to fully inform those in the ordinary skill of the scope of the invention.

[0027] Throughout the specification, when it is referred to that one component, such as a layer, film, region, or substrate, is located "on top of" another component, it can be interpreted that the one component may be in direct contact with the other component, or that there may be other components interposed between them.

[0028] Furthermore, relative terms such as "upper" or "lower" may be used here to describe the relative relationship of one element to other elements, as shown in the diagram. It should be understood that relative terms are intended to include other directions of the element in addition to the directions depicted in the diagram. The drawings may be exaggerated to illustrate the invention in detail, and the same reference numerals in the drawings refer to the same component.

[0029] Figure 1 is a schematic diagram showing a substrate processing apparatus according to an embodiment of the present invention.

[0030] Referring to Figure 1, a substrate processing apparatus according to an embodiment of the present invention is an apparatus for forming a thin film, for example, a silicon insulating film, and comprises a chamber 10, a substrate support section 20 provided within the chamber 10 for supporting a substrate disposed within the chamber 10, a gas injection section 30 provided within the chamber 10 so as to be opposite the substrate support section 20 for injecting process gas toward the substrate support section 20, and a gas supply section 40 for supplying gas to the gas injection section 30. The substrate processing apparatus may further comprise an RF power supply 50 for supplying power to generate plasma within the chamber 10 and a control section (not shown) for controlling the RF power supply 50. Here, the gas injection section 30 is formed with a first gas supply path for supplying a first gas and a second gas supply path for supplying a second gas, separated from each other.

[0031] The chamber 10 provides a predetermined reaction space and maintains it in an airtight manner. The chamber 10 may comprise a body 12 having a predetermined reaction space with a generally circular or rectangular planar portion and side walls extending upward from the planar portion, and a lid 14 positioned on the body 12 in a generally circular or rectangular shape to maintain the reaction space in an airtight manner. However, the chamber 10 is not limited in any way and can be manufactured in a wide variety of shapes corresponding to the shape of the substrate.

[0032] An exhaust port (not shown) is formed in a predetermined area on the lower surface of the chamber 10, and an exhaust pipe (not shown) connected to the exhaust port may be provided on the outside of the chamber 10. The exhaust pipe may also be connected to an exhaust device (not shown). A vacuum pump such as a turbomolecular pump can be used as the exhaust device. Therefore, the inside of the chamber 10 can be evacuated to a predetermined reduced pressure atmosphere, for example, a predetermined pressure of 0.1 mTorr or less, by the exhaust device. The exhaust pipe may be arranged not only on the lower surface of the chamber 10, but also on the side of the chamber 10 below the substrate support section 20, which will be described later. It goes without saying that in order to shorten the exhaust time, a number of exhaust pipes and associated exhaust devices may be further arranged.

[0033] On the other hand, a substrate disposed in the chamber 10 for the substrate processing process may be placed on the substrate support section 20. Here, the substrate may be a silicon wafer or a glass substrate, or a substrate on which a separate thin film has already been formed. The substrate support section 20 may be equipped with, for example, an electrostatic chuck to hold the substrate by electrostatic force, or it may be supported by vacuum suction or mechanical force so that such a substrate can be placed on and supported.

[0034] The substrate support portion 20 may be provided in a shape corresponding to the shape of the substrate, for example, circular or rectangular. The substrate support portion 20 may include a substrate support base 22 on which the substrate is placed and a lifter 24 positioned below the substrate support base 22 to raise and lower the substrate support base 22. Here, the substrate support base 22 may be made larger than the substrate, and the lifter 24 is provided to support at least one area of ​​the substrate support base 22, for example, the center, and when a substrate is placed on the substrate support base 22, it may move the substrate support base 22 closer to the gas injection unit 30. In addition, a heater (not shown) may be provided inside the substrate support base 22. The heater generates heat to a predetermined temperature to heat the substrate support base 22 and the substrate placed on the substrate support base 22, so that a thin film is deposited uniformly on the substrate.

[0035] The gas supply unit 40 may be located at least partially outside the chamber 10 and supplies gas to the gas injection unit 30. The gas supply unit 40 may include a first gas supplyer 42 and a second gas supplyer 44. The first gas supplyer 42 and the second gas supplyer 44 may be connected to various gas storage devices (not shown) and supply the gas required for the process to the reaction space via the gas injection unit 30, or they may consist of piping connecting the gas storage device and the gas injection unit 30 to transmit the gas from the gas storage device to the gas injection unit 30.

[0036] For example, the source gas may be supplied to the reaction space via the first gas supply 42, and the reactant gas may be supplied to the reaction space via the second gas supply 44. However, the present invention is not limited thereto, and it goes without saying that, conversely, the source gas may be supplied to the reaction space via the first gas supply 42 and the reactant gas may be supplied to the reaction space via the second gas supply 44. Furthermore, at least one of the first gas supply 42 and the second gas supply 44 may supply a gas for plasma treatment of the substrate. For example, the plasma treatment gas may be supplied to the reaction space via the second gas supply 44, but the present invention is not limited thereto, and the plasma treatment gas may be supplied to the reaction space via the first gas supply 42, or via both the first gas supply 42 and the second gas supply 44. Furthermore, at least one of the first gas supply unit 42 and the second gas supply unit 44 may supply an inert gas such as argon (Ar) gas or a less reactive gas such as nitrogen (N2) gas. In this case, the first gas supply unit 42 and the second gas supply unit 44 do not necessarily each supply only one gas; they may each be configured to supply multiple gases simultaneously, or to supply a gas selected from among multiple gases.

[0037] The gas injection unit 30 is disposed inside the chamber 10, for example, on the lower surface of the lid 14. Inside the gas injection unit 30, a first gas supply path connected to a first gas supply 42 and a second gas supply path connected to a second gas supply 44 are formed. The first gas supply path and the second gas supply path are formed to be independent of and separate from each other, so that the gas supplied from the first gas supply 42 and the gas supplied from the second gas supply 44 do not mix inside the gas injection unit 30 and are supplied separately to the substrate.

[0038] The gas injection unit 30 may include an upper frame 32 and a lower frame 34. Here, the upper frame 32 is detachably coupled to the lower surface of the lid 14, and a part of its upper surface, for example, the center of the upper surface, is separated from the lower surface of the lid 14 by a predetermined distance. This allows the gas from the first gas supply unit 42 to diffuse in the space between the upper surface of the upper frame 32 and the lower surface of the lid 14. The lower frame 34 is disposed on the lower surface of the upper frame 32 at a certain distance. This allows the gas from the second gas supply unit 44 to diffuse in the space between the upper surface of the lower frame 34 and the lower surface of the upper frame 32. The upper frame 32 and the lower frame 34 may be connected along their outer circumferential surfaces to form a partitioned space inside and be integrally formed, and it goes without saying that the outer circumferential surfaces are sealed by a separate sealing member.

[0039] The first gas supply path may be configured such that gas from the first gas supply unit 42 diffuses in the space between the lower surface of the lid 14 and the upper frame 32, and is supplied to the inside of the chamber 10 by penetrating the upper frame 32 and the lower frame 34. The second gas supply path may be configured such that gas from the second gas supply unit 44 diffuses in the space between the lower surface of the upper frame 32 and the upper surface of the lower frame 34, and is supplied to the inside of the chamber 10 by penetrating the lower frame 34. The first gas supply path and the second gas supply path do not have to communicate with each other, so that the gas supplied from the first gas supply unit 42 and the gas supplied from the second gas supply unit 44 can be supplied to the inside of the chamber 10 separately via the gas injection unit 30.

[0040] A first electrode 38 may be disposed on the lower surface of the lower frame 34, and a second electrode 36 may be disposed on the lower side of the lower frame 24 and outside the first electrode 28 at a predetermined distance apart. In this case, the lower frame 34 and the second electrode 36 may be formed by connecting them along their outer surfaces, and it goes without saying that the outer surfaces may be sealed by a separate sealing member.

[0041] In this manner, when the first electrode 38 and the second electrode 36 are arranged, the gas supplied from the first gas supplyer 42 may be injected through the first electrode 38 onto the substrate, and the gas supplied from the second gas supplyer 44 may be injected onto the substrate through the separation space between the first electrode 38 and the second electrode 36.

[0042] RF power may be supplied from the RF power supply 50 to either the lower frame 34 or the second electrode 36. For example, the lower frame 34 may be grounded, and RF power may be supplied from the RF power supply 50 to the second electrode 36. When the lower frame 34 is grounded, the first electrode 38 disposed on the lower surface of the lower frame 34 is also grounded. Therefore, when RF power is supplied to the second electrode 36, a first activation region, i.e., a first plasma region, can be formed between the gas injection unit 30 and the substrate support unit 20, and a second activation region, i.e., a second plasma region, can be formed between the first electrode 38 and the second electrode 36.

[0043] The silicon insulating film formation method of the present invention will be described in detail below with reference to Figures 2 and 3. The silicon insulating film formation method according to the embodiment of the present invention may also be performed using the substrate processing apparatus described above, and therefore, explanations that overlap with the above-mentioned content in relation to the substrate processing apparatus will be omitted.

[0044] Figure 2 is a schematic diagram showing a method for forming a silicon insulating film according to one embodiment of the present invention.

[0045] Referring to Figure 2, a method for forming a silicon insulating film according to one embodiment of the present invention is a method for forming an oxygen-doped silicon insulating film, comprising the steps of providing a substrate in a reaction space (S100), forming a silicon insulating film on the substrate using an atomic layer deposition process (S200), and forming a plasma in the reaction space using an oxygen-containing gas in order to dope the silicon insulating film with oxygen (S300). Here, at least one of the steps of forming the silicon insulating film (S200) and forming a plasma in the reaction space using an oxygen-containing gas (S300) may be performed multiple times.

[0046] In the step of providing the substrate (S100), the substrate is provided in the reaction space of the chamber 10. In the step of providing the substrate (S100), the substrate may be brought into the reaction space of the chamber 10 and placed on the substrate support section 20. As mentioned above, the substrate may be a silicon wafer or a glass substrate, or a substrate on which a separate thin film has already been formed. Here, the substrate support section 20 may be provided with, for example, an electrostatic chuck to hold the substrate by electrostatic force, or it may be supported by vacuum suction or mechanical force so that the substrate can be placed on and supported.

[0047] In the step of forming the silicon insulating film (S200), the silicon insulating film is formed on a substrate provided in the reaction space of the chamber 10. Here, the silicon insulating film is doped with oxygen by a plasma treatment process described later and can be used as a dielectric for semiconductor devices. For example, the silicon insulating film may include an interlayer insulating film (ILD) such as a spacer for the gate electrode in a thin film transistor (TFT).

[0048] In embodiments of the present invention, the step of forming the silicon insulating film (S200) may be carried out by a low-temperature process at 600°C or lower. For example, the step of forming the silicon insulating film (S200) may be carried out by controlling the temperature of the substrate to 100°C or higher and 400°C or lower, or by controlling the temperature of the reaction space in the chamber 10 to 100°C or higher and 400°C or lower. The silicon insulating film can be formed by a low-temperature process at 100 to 400°C using an atomic layer deposition (ALD) method, which involves performing multiple deposition cycles in which the source gas and reactant gas are supplied in that order. This will be explained in more detail below.

[0049] In the step of supplying the source gas (S210), a source gas containing silicon (Si) is supplied onto the substrate. Here, in the step of supplying the source gas (S210), the source gas containing silicon (Si) may be supplied onto the substrate via the first gas supply path of the substrate processing apparatus described above. In this case, the source gas containing silicon (Si) may include silane, disilane, trisilane, and gases in which any of the silanes is substituted with an amine. For example, the source gas may contain TSA (trisilylamine). In the step of supplying the source gas (S210), the source gas containing silicon (Si) is sprayed onto the substrate and adsorbed. At this time, the step of supplying the source gas (S210) may be performed without supplying the RF power supply 50.

[0050] A step of purging the source gas (S220) may be performed after the step of supplying the source gas (S210). In the step of purging the source gas (S220), any source gas remaining in the reaction space of the chamber 10 may be removed. Such a step of purging the source gas (S220) may be performed by supplying an inert gas, such as argon (Ar) gas, to the reaction space, and the argon (Ar) gas may be supplied via at least one of the first gas supply path and the second gas supply path. In this case, the RF power supply 50 may not be supplied while the source gas is being purged.

[0051] Following the step of purging the source gas (S220), the step of supplying reactant gas (S230) is performed. In the step of supplying reactant gas (S230), a reactant gas containing nitrogen is supplied onto the substrate. That is, in the step of supplying reactant gas (S230), a reactant gas containing nitrogen (N) may be supplied onto the substrate. Here, in the step of supplying reactant gas (S230), a reactant gas containing nitrogen may be supplied onto the substrate via the second gas supply path of the substrate processing apparatus described above. In this case, the reactant gas containing nitrogen may contain ammonia (NH3) gas or nitrous oxide (N2O) gas. When reactant gas is supplied onto a substrate on which raw material substances are adsorbed, the raw material substances react with the reactants contained in the reactant gas.

[0052] In this case, the step of supplying the reactant gas (S230) may be performed without supplying the RF power supply 50. However, the present invention is not limited in any way, and in the step of supplying the reactant gas (S230), the RF power supply 50 may be supplied to the reaction space to activate the reactant gas and generate plasma in order to effectively react the reactant with the raw material. In this way, when the reactant gas is supplied after being activated in the step of supplying the reactant gas (S230), the supplied nitrogen-containing gas is activated into nitrogen radicals and reacted, making it possible to form a silicon insulating film on the substrate at an even lower process temperature.

[0053] Following the step of supplying the reactant gas (S230), a step of purging the reactant gas (S240) may be performed. In the step of purging the reactant gas (S240), any reactant gas remaining in the reaction space of the chamber 10 may be removed. Such a step of purging the reactant gas (S240) may be performed by supplying an inert gas, such as argon (Ar) gas, into the reaction space, similar to the step of purging the source gas (S220), and the argon (Ar) gas may be supplied via at least one of the first gas supply path and the second gas supply path.

[0054] A method for forming a silicon insulating film according to an embodiment of the present invention may include the step (S300) of doping the silicon insulating film with oxygen and forming a plasma using an oxygen-containing gas in the reaction space in order to adjust the hydrogen content of the silicon insulating film.

[0055] In other words, in the step of forming a silicon insulating film (S200), a deposition process cycle is performed which includes a step of supplying a source gas (S210), a step of purging the source gas (S220), a step of supplying a reactant gas (S230), and a step of purging the reactant gas (S240) to form the silicon insulating film. At this time, in the silicon insulating film formation method according to the embodiment of the present invention, a step of forming a plasma (300) is performed to dope the silicon insulating film with oxygen before the silicon insulating film of the desired thickness is formed, so that the hydrogen content of the silicon insulating film can be adjusted. Here, the step of forming a plasma (300) may be performed selectively. That is, in the step of forming a plasma (S300), it is selected whether or not to perform a plasma treatment step after at least one deposition process cycle has been performed, and if it is selected to perform a plasma treatment step, the plasma treatment step is performed while the silicon insulating film is being formed to the desired thickness. For this purpose, the step of forming plasma (S300) may include, after at least one deposition cycle has been performed, a step of selecting whether or not to perform a plasma treatment step (S310), and, if the plasma treatment step is selected, a step of supplying an oxygen-containing gas to the reaction space (S330).

[0056] The step of selecting whether or not to perform the plasma treatment process (S310) may be performed after at least one deposition process cycle has been completed. That is, the step of selecting whether or not to perform the plasma treatment process (S310) may be performed after one deposition process cycle has been completed, which includes the steps of supplying source gas (S210), purging source gas (S220), supplying reactant gas (S230), and purging reactant gas (S240), or it may be performed after two or more such cycles have been completed. Whether or not to perform the plasma treatment process is selectable by the user, and for this purpose, the substrate processing apparatus may be equipped with a user interface (UI), such as a human-machine interface (HMI), for receiving information from the user regarding whether or not to perform the plasma treatment process.

[0057] If it is chosen not to perform the plasma treatment process, an additional deposition cycle is performed following the step of choosing whether or not to perform the plasma treatment process (S310). That is, if it is chosen not to perform the plasma treatment process in the step of choosing whether or not to perform the plasma treatment process (S310) after the step of purging the reactant gas during the deposition cycle (S240), the step of supplying the source gas for the next deposition cycle (S210) is performed.

[0058] In contrast, if a plasma treatment process is selected, that is, if a plasma treatment process is selected, the step of supplying an oxygen-containing gas to the reaction space (S330) is performed. Here, the silicon insulating film formation method according to the embodiment of the present invention may include a step of filling an oxygen-containing gas storage space with an oxygen-containing gas (S320) before the step of supplying an oxygen-containing gas to the reaction space (S330). In this case, the step of filling an oxygen-containing gas (S320) may include a step of isolating the storage space for storing the oxygen-containing gas, i.e., the storage container, from the reaction space and a step of filling the storage space completely with an oxygen-containing gas.

[0059] As described later, the plasma treatment process involves supplying an oxygen-containing gas onto a substrate on which a silicon insulating film is formed, thereby doping the silicon insulating film with oxygen and removing hydrogen contained in the silicon insulating film. For the plasma treatment process to be carried out efficiently, a uniform flow rate of gas per unit time is required. That is, the oxygen-containing gas must be supplied uniformly from the start section of the plasma treatment process, where the supply of oxygen-containing gas begins, to the end section of the plasma treatment process, where the supply of oxygen-containing gas ends.

[0060] For this reason, the step of isolating the storage space for storing oxygen-containing gas from the reaction space involves closing a valve (not shown) located in the oxygen-containing gas supply line connected to the storage unit to isolate the storage unit from the reaction space. Here, the oxygen-containing gas supply line may mean at least a portion of the path for supplying oxygen-containing gas to the gas injection unit 30. For example, if oxygen-containing gas is supplied to the gas injection unit 30 via a second gas supply unit 44, the oxygen-containing gas supply line may be at least a portion of the second gas supply unit 44. For this reason, in the step of isolating the storage space for storing oxygen-containing gas from the reaction space, the oxygen-containing gas supply line can be closed by closing a valve (not shown) located in the second gas supply unit 44 that can control the supply of oxygen-containing gas.

[0061] In the step of filling the storage space with oxygen-containing gas, the oxygen-containing gas supply line remains closed while the storage container is continuously supplied with oxygen-containing gas. In this case, the storage container is completely filled with oxygen-containing gas. Therefore, when the valve is opened all at once thereafter to connect the storage space and the reaction space, the oxygen-containing gas can be supplied uniformly from the start section of the plasma processing process where the oxygen-containing gas supply begins.

[0062] In step (S320) of filling a storage space for storing oxygen-containing gas with oxygen-containing gas, an inert gas, such as argon (Ar) gas, may be continuously supplied to the reaction space. For example, if the second gas supplier 44 forms a supply line for oxygen-containing gas, the inert gas may be supplied to the reaction space via the first gas supplier 42. In this way, by supplying the inert gas to the reaction space via the first gas supplier 42 in step (S320) of filling a storage space for storing oxygen-containing gas, by-products and residual gases generated in previous deposition cycles can be purged out and removed from the reaction space, thereby preventing unwanted reactions of the oxygen-containing gas.

[0063] In step (S330), supplying an oxygen-containing gas to the reaction space, a valve installed in the oxygen-containing gas supply line is opened to connect the storage space for storing the oxygen-containing gas to the reaction space. At this time, in step (S330), the valve installed in the oxygen-containing gas supply line may be opened to its maximum extent at once to open the oxygen-containing gas supply line to its maximum extent at once. Here, the oxygen-containing gas may be at least one of nitrous oxide (N2O), ozone (O3), water (H2O), and oxygen (O2). In addition, such an oxygen-containing gas may be supplied together with at least one of ammonia (NH3), nitrogen (N2), and argon (Ar). That is, the gas supplied to the reaction space may be a combination of one or more of nitrous oxide (N2O), ozone (O3), water (H2O), ammonia (NH3), nitrogen (N2), oxygen (O2), and argon (Ar). For example, when nitrous oxide (N2O) gas is supplied to the reaction space, the nitrous oxide (N2O) may substitute with molecules of silicon bonded to hydrogen (Si-H) and, optionally, molecules of nitrogen bonded to hydrogen (NH molecules) contained in the silicon insulating film, as shown in the reaction equation below, thereby doping the silicon insulating film with oxygen. Furthermore, this allows for the removal of hydrogen contained in the silicon insulating film at the atomic layer level.

[0064] <Reaction Equation> TIFF2026511568000002.tif12170

[0065] In this case, the step of supplying an oxygen-containing gas to the reaction space (S330) may include the step of forming a plasma using the oxygen-containing gas in the reaction space. That is, in the step of supplying an oxygen-containing gas to the reaction space (S330), an RF power supply 50 may be supplied to the reaction space to activate the oxygen-containing gas and generate a plasma in order to effectively react the nitrogen-hydrogen-bonded molecules (NH molecules) and silicon-hydrogen-bonded molecules (Si-H) contained in the silicon insulating film with the oxygen-containing gas. In this way, by activating the oxygen-containing gas in the reaction space and forming an oxygen-containing gas plasma in the step of supplying an oxygen-containing gas (S330), hydrogen contained in the silicon insulating film can be removed and oxygen can be doped at a low temperature. For example, when nitrous oxide (N2O) gas is activated and supplied onto the substrate, hydrogen contained in the silicon insulating film can be effectively removed at a low temperature of 100°C or higher and 400°C or lower.

[0066] After the step of supplying an oxygen-containing gas to the reaction space (S330), a step of selecting whether or not to perform a vapor deposition process (S400) may be performed. If it is selected to terminate the vapor deposition process in the step of selecting whether or not to perform the vapor deposition process (S400), the silicon insulating film formation process, including the step of forming a silicon insulating film (S200) and the step of forming a plasma (S300), is terminated. On the other hand, if it is selected to continue the vapor deposition process in the step of selecting whether or not to perform the vapor deposition process (S400), the step of forming the silicon insulating film (S200) is performed. That is, if it is selected to continue the vapor deposition process in the step of selecting whether or not to perform the vapor deposition process (S400), a step of supplying the source gas for the next vapor deposition process cycle (S210) may be performed. In addition, although not shown in the figures, it is also possible to select a step of forming a plasma, i.e., to perform further plasma treatment, in the step of selecting whether or not to perform the vapor deposition process (S400). As mentioned above, such selections of steps are also made by the user via the user interface.

[0067] If, in the step of selecting whether or not to perform the deposition process (S400), it is selected to continue the deposition process, the step of filling the source gas storage space with source gas may be performed. In this case, the step of filling the source gas may include the step of isolating the storage space for storing the source gas from the reaction space and the step of filling the storage space for storing the source gas completely with source gas. Here, the principle of the step of filling the source gas is the same as the step of filling the storage space with an oxygen-containing gas (S320) described above, so redundant explanation will be omitted. In this way, if the source gas is supplied to the reaction space all at once in the step of supplying the source gas after the plasma treatment process (S210), the source gas can be supplied uniformly from the start section of the deposition process when the source gas supply begins.

[0068] At this time, in the step of filling the storage space for storing the source gas with the source gas, an inert gas, such as argon (Ar) gas, may be continuously supplied to the reaction space. That is, if the first gas supplier 42 forms the source gas supply line, the inert gas may be supplied to the reaction space via the second gas supplier 44. In this way, by supplying the inert gas to the reaction space via the second gas supplier 44 in the step of filling the source gas supply line with the source gas, by-products and residual gases generated in the previous treatment process can be purged out and removed from the reaction space, thereby preventing unwanted reactions of the source gas.

[0069] Thus, according to the embodiments of the present invention, by subjecting a silicon insulating film to plasma treatment using a gas containing oxygen, the silicon insulating film can be doped with oxygen, and hydrogen contained within the silicon insulating film can be removed at the atomic layer level.

[0070] Furthermore, in the silicon insulating film formation method according to the embodiment of the present invention, a plasma treatment process cycle is selectively carried out to dope the silicon insulating film with oxygen and remove hydrogen from the silicon insulating film while performing a deposition process cycle to deposit the silicon insulating film to a desired thickness. Here, as the number of plasma process cycles is performed increases, the concentration of oxygen doped into the silicon insulating film may increase and the hydrogen content may decrease. However, if the number of plasma process cycles is performed increases excessively, the composition of the silicon insulating film may change undesirably. That is, as mentioned above, the silicon insulating film can have hydrogen removed by a substitution reaction with nitrous oxide (N2O) contained in the plasma gas, but if the number of plasma process cycles is performed excessively, there is a risk that the oxygen content of the silicon insulating film will increase excessively. For this reason, in the silicon insulating film formation method according to the embodiment of the present invention, by selectively performing a treatment process after at least one deposition process cycle has been performed, the hydrogen content in the oxygen-doped silicon insulating film can be effectively controlled, and the composition of the silicon insulating film that changes with plasma treatment can also be effectively controlled.

[0071] Figure 3 is a schematic diagram illustrating a method for forming a silicon insulating film according to another embodiment of the present invention.

[0072] Referring to Figure 3, another embodiment of the present invention provides a method for forming a silicon insulating film, which includes the steps of: providing a substrate in a reaction space (S100); supplying a silicon-containing gas and a nitrogen-containing gas onto the substrate and forming a silicon insulating film by a chemical vapor deposition process (S200); and forming a plasma in the reaction space using an oxygen-containing gas to dope the silicon insulating film with oxygen (S300). Here, at least one of the steps of forming the silicon insulating film (S200) and forming a plasma in the reaction space using an oxygen-containing gas (S300) may be performed multiple times.

[0073] The method for forming a silicon insulating film according to another embodiment of the present invention differs from the aforementioned embodiment of the present invention only in the step of forming the silicon insulating film (S200). The steps of providing a substrate in the reaction space (S100) and forming a plasma (S300) are directly applicable to the steps described above. Therefore, redundant explanations of the steps of providing a substrate (S100) and forming a plasma (S300) in the other embodiment of the present invention are omitted.

[0074] Here, the step of forming the silicon insulating film (S200) is carried out by a chemical vapor deposition (CVD) process in which a source gas and a reactant gas are supplied simultaneously. In this case, the source gas may be a silicon-containing gas, and may include silane, disilane, trisilane, and gases in which any of the silanes is substituted with an amine. For example, the source gas may contain TSA (trisilylamine). The reactant gas may be a nitrogen-containing gas, and may include ammonia (NH3) gas or nitrous oxide (N2O) gas. In another embodiment of the present invention, the step of forming the silicon insulating film (S200) is carried out by a chemical vapor deposition process in which such a source gas and a reactant gas are supplied simultaneously.

[0075] In this case, the step of forming the silicon insulating film (S200) may be carried out without supplying the RF power supply 50. However, the present invention is not limited in any way, and in the step of forming the silicon insulating film (S200), the RF power supply 50 may be supplied to the reaction space so as to generate plasma in order to effectively react the reactant with the raw material. Furthermore, the step of forming the silicon insulating film (S200) may be carried out by a low-temperature process at 600°C or below, or by controlling the temperature of the substrate to 100°C or above and 400°C or below, or by controlling the temperature of the reaction space of the chamber 10 to 100°C or above and 400°C or below.

[0076] After the step of forming a silicon insulating film by chemical vapor deposition (S200), a step of forming a plasma using an oxygen-containing gas in the reaction space to dope the silicon insulating film with oxygen and adjust the hydrogen content of the silicon insulating film (S300) may be performed. In this case, the step of forming the silicon insulating film (S200) may be performed again after the step of forming the plasma (S300), as in the embodiment described above.

[0077] Furthermore, in the step of forming the plasma (S300), as described above, one or more gases selected from nitrous oxide (N2O), ozone (O3), water (H2O), ammonia (NH3), nitrogen (N2), oxygen (O2), and argon (Ar) may be supplied to the reaction space. The step of forming the plasma (S300) may include the steps of isolating a storage space for storing oxygen-containing gas from the reaction space, filling the storage space with oxygen-containing gas, and connecting the storage space to the reaction space to supply oxygen-containing gas to the reaction space. In this case, in the step of supplying oxygen-containing gas, the supply line connecting the storage space and the reaction space may be opened to its maximum extent at once to supply the oxygen-containing gas. Thus, after performing the step of forming the plasma (S300), if it is selected to continue the deposition process in the step of selecting whether or not to perform the deposition process (S400), the step of filling the source gas storage space and the reactant gas storage space with source gas and reactant gas, respectively, may be performed. Here, the step of filling the source gas storage space and the reactant gas storage space with source gas and reactant gas, respectively, is similar in principle to the step of filling the storage space with an oxygen-containing gas (S320) described above, so a redundant explanation will be omitted.

[0078] Thus, according to the embodiments of the present invention, by subjecting a silicon insulating film to plasma treatment using a gas containing oxygen, the silicon insulating film can be doped with oxygen, and hydrogen contained within the silicon insulating film can be removed at the atomic layer level.

[0079] Furthermore, by selectively performing plasma treatment, the hydrogen content in the oxygen-doped silicon insulating film can be effectively controlled, and the components of the silicon insulating film that change with plasma treatment can also be effectively controlled.

[0080] Although preferred embodiments of the present invention have been described and illustrated using specific terminology, these terms are merely for the purpose of clearly explaining the present invention, and it is clear that various modifications and changes can be made to the embodiments and terminology described herein without departing from the technical spirit and scope of the appended claims. These modified embodiments should not be understood individually from the spirit and scope of the present invention, but should be considered to fall within the scope of the claims of the present invention.

Claims

1. A method for forming an oxygen-doped silicon insulating film, The steps include: placing a substrate in the reaction space, The steps include forming a silicon insulating film on the aforementioned substrate using an atomic layer deposition process, The steps include forming a plasma in the reaction space using an oxygen-containing gas in order to dope the silicon insulating film with oxygen, A method for forming a silicon insulating film, including [a specific component].

2. The method for forming a silicon insulating film according to claim 1, wherein at least one of the steps of forming the silicon insulating film and forming the plasma is performed multiple times.

3. A method for forming a silicon insulating film according to claim 1, wherein the step of forming the silicon insulating film is performed after the step of forming the plasma.

4. The step of forming the plasma is, Nitrous oxide (N ２ O), ozone (O ３ ), water (H ２ O), ammonia (NH ３ ), nitrogen (N ２ ), oxygen (O ２ A method for forming a silicon insulating film according to claim 1, comprising the step of supplying a gas that is a combination of one or more of the following: silicon () and argon (Ar) to the reaction space.

5. The step of forming the silicon dielectric is, The steps include supplying a source gas containing TSA (trisilylamine), The steps include supplying a reactant gas containing nitrogen, A method for forming a silicon nitride film according to claim 1, including the method described in claim 1.

6. The step of forming the plasma is, A step of isolating a storage space for storing oxygen-containing gas from the reaction space, The steps include filling the aforementioned storage space with an oxygen-containing gas, The steps include: connecting the storage space to the reaction space and supplying an oxygen-containing gas to the reaction space; A method for forming a silicon nitride film according to claim 1, including the method described in claim 1.

7. In the step of supplying the oxygen-containing gas, The method for forming a silicon nitride film according to claim 6, wherein the supply line connecting the storage space and the reaction space is opened to its maximum extent at once to supply an oxygen-containing gas.

8. A substrate processing method according to any one of claims 1 to 7, wherein the temperature of the substrate or the reaction space is maintained at a temperature of 100 to 400°C.

9. A method for forming an oxygen-doped silicon insulating film, The steps include: placing a substrate in the reaction space, The steps include supplying a silicon-containing gas and a nitrogen-containing gas onto the substrate to form a silicon insulating film by a chemical vapor deposition process, The steps include forming a plasma in the reaction space using an oxygen-containing gas in order to dope the silicon insulating film with oxygen, A method for forming a silicon insulating film, including [a specific component].

10. The method for forming a silicon insulating film according to claim 9, wherein at least one of the steps of forming the silicon insulating film and forming the plasma is performed multiple times.

11. A method for forming a silicon insulating film according to claim 9, wherein the step of forming the silicon insulating film is performed after the step of forming the plasma.

12. The step of forming the plasma is, Nitrous oxide (N ２ O), ozone (O ３ ), water (H ２ O), ammonia (NH ３ ), nitrogen (N ２ ), oxygen (O ２ ), or argon (Ar), and supplying a gas combined with one or more of them to the reaction space, the method for forming a silicon insulating film according to claim 9.

13. The method for forming a silicon nitride film according to claim 9, wherein the silicon-containing gas is TSA (trisilylamine).

14. The step of forming the plasma is, A step of isolating a storage space for storing oxygen-containing gas from the reaction space, The steps include filling the aforementioned storage space with an oxygen-containing gas, The steps include: connecting the storage space to the reaction space and supplying an oxygen-containing gas to the reaction space; A method for forming a silicon nitride film according to claim 9, including the method described in claim 9.

15. In the step of supplying the oxygen-containing gas, A method for forming a silicon nitride film according to claim 14, wherein a supply line connecting the storage space and the reaction space is opened to its maximum extent at once to supply an oxygen-containing gas.

16. A substrate processing method according to any one of claims 9 to 15, wherein the temperature of the substrate or the reaction space is maintained at a temperature of 100 to 400°C.

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