KR102202089B1 - Method of fabricating nitride film - Google Patents

Abstract

The present invention relates to a method of manufacturing a nitride film capable of easily controlling compressive stress while stably maintaining a film quality by using an atomic layer deposition method. The source gas is provided on the substrate by providing a source gas on a substrate disposed in a chamber. A first step in which at least a part of is adsorbed, a second step of providing a first purge gas on the substrate, a stress control gas including nitrogen gas (N ₂ ) on the substrate and the nitrogen gas (N ₂ ) A third step of forming a unit deposition film on the substrate by providing a reaction gas containing nitrogen component (N) in a plasma state, a fourth step of providing a second purge gas on the substrate, and after the first step Before the second step, by performing at least one unit cycle including the step of stopping the supply of the source gas and maintaining the pressure in the chamber lower than in the first step, thereby generating compressive stress on the substrate. A nitride film is formed.

Description

Method of fabricating nitride film {Method of fabricating nitride film}

The present invention relates to a method of manufacturing a nitride film, and more particularly, to a method of manufacturing a nitride film using an atomic layer deposition method.

In a method of improving the performance of an electronic device, there is a method of changing the electrical properties of an upper or lower material deformed by a nitride film having stress. For example, in CMOS device fabrication, a nitride film having a compressive stress may be formed on the PMOS regions so that a local lattice strain occurs in the channel region of the transistor. In this case, it is necessary to control the level of stress generated in the deposited nitride within a predetermined range. However, a known method for producing nitride has a problem in that it is not easy to properly control the stress level of the nitride while stably maintaining the film quality of the nitride.

The present invention has been made to solve various problems including the above problems, and an object of the present invention is to provide a method of manufacturing a nitride film having a predetermined compressive stress while maintaining good film quality. However, these problems are exemplary, and the scope of the present invention is not limited thereby.

A method of manufacturing a nitride film according to an aspect of the present invention for solving the above problems is provided. In the method of manufacturing the nitride film, a first step of providing a source gas on a substrate disposed in a chamber to adsorb at least a portion of the source gas on the substrate; A second step of providing a first purge gas on the substrate; To provide a reaction gas containing nitrogen (N) outside the stress control gas and the nitrogen gas (N ₂₎ having a nitrogen gas (N ₂₎ on the substrate to a plasma state to form a unit deposition film on the substrate The third step; A fourth step of providing a second purge gas on the substrate; And stopping the supply of the source gas and maintaining the pressure in the chamber lower than that in the first step, after the first step and before the second step, by performing at least one unit cycle including A nitride film having compressive stress is formed on the substrate.

In the method of manufacturing the nitride film, the step of maintaining the pressure in the chamber lower than in the first step may be implemented by stopping the supply of the source gas and performing pumping in the chamber. Furthermore, the pumping may be performed at all times throughout the unit cycle.

In the method of manufacturing the nitride film, in the unit cycle, after the third step and before the fourth step, the provision of the stress control gas and the reaction gas is stopped, and the pressure in the chamber is kept lower than in the third step. Step; may include.

In the method of manufacturing the nitride film, the step of maintaining the pressure in the chamber lower than in the third step may be implemented by stopping the supply of the stress control gas and the reaction gas, but performing pumping in the chamber. Furthermore, the pumping may be performed at all times throughout the unit cycle.

The method of manufacturing the nitride film may be performed to increase the amount of the nitrogen gas N ₂ provided on the substrate in the third step as the required compressive stress of the nitride film increases.

In the method of manufacturing the nitride film, the stress control gas may include a mixed gas of an inert gas and argon gas (Ar). The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). Further, as the required compressive stress of the nitride layer increases in the third step, the relative ratio of the nitrogen gas N ₂ to the inert gas provided on the substrate may be increased.

In the method of manufacturing the nitride film, in the third step, in order to additionally control the compressive stress of the nitride film, the power or frequency of the power applied to form the plasma may be adjusted.

In the method of manufacturing the nitride film, the plasma may be formed by a direct plasma method or a remote plasma method.

In the method of manufacturing the nitride film, the plasma may be formed in a showerhead disposed on the substrate and provided on the substrate.

In the method of manufacturing the nitride film, the first purge gas or the second purge gas may be continuously supplied in the first to fourth steps.

In the method of manufacturing the nitride film, at least one of the first purge gas and the second purge gas may be nitrogen gas or an inert gas. Alternatively, at least one of the first purge gas and the second purge gas may be a mixed gas consisting of nitrogen gas and an inert gas. Further, the stress control gas including nitrogen gas (N ₂ ) may be a gas composed of a material of the same kind as at least one of the first purge gas and the second purge gas. The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

In the method of manufacturing the nitride film, the unit cycle includes: a fifth step of providing a second stress control gas on the unit deposition film in a plasma state; And a sixth step of providing a third purge gas on the substrate.

In the method of manufacturing the nitride film, the second stress control gas may include nitrogen gas (N ₂ ), or the second stress control gas may include a mixed gas of an inert gas and nitrogen gas (N ₂ ). . The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

In the method of manufacturing the nitride film, the first purge gas, the second purge gas, or the third purge gas may be continuously supplied in the first to sixth steps.

In the method of manufacturing the nitride film, at least one of the first purge gas, the second purge gas, and the third purge gas may be nitrogen gas or an inert gas. The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

In the method of manufacturing the nitride film, at least one of the first purge gas, the second purge gas, and the third purge gas may be a mixed gas consisting of nitrogen gas and an inert gas. The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

In the method of manufacturing the nitride film, the stress control gas may be a gas composed of a material identical to at least one of the first purge gas, the second purge gas, and the third purge gas.

In the method of manufacturing the nitride film, the reaction gas containing the nitrogen component (N) may include ammonia (NH ₃ ) gas.

According to some embodiments of the present invention made as described above, it is possible to provide a method of manufacturing a nitride capable of appropriately controlling the stress level of the nitride while stably maintaining the film quality of the nitride. Of course, the scope of the present invention is not limited by these effects.

1 is a flow chart illustrating a unit cycle of an atomic layer deposition method in a method of manufacturing a nitride film according to the technical idea of the present invention.
FIG. 2 is a diagram illustrating a series of processes sequentially from left to right, which a substrate passes over time during a unit cycle in a method of manufacturing a nitride film according to an embodiment of the present invention.
FIG. 3 is a diagram illustrating a series of processes sequentially from left to right by a substrate over time during a unit cycle in a method of manufacturing a nitride film according to another embodiment of the present invention.
4 is a flow chart illustrating a unit cycle of an atomic layer deposition method in a method of manufacturing a nitride film according to another technical idea of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Throughout the specification, when referring to that one component such as a film, region, or substrate is positioned "on" another component, the one component directly contacts "on" the other component, or It can be interpreted that there may be other components interposed therebetween. On the other hand, when it is mentioned that one component is positioned "directly on" another component, it is interpreted that there are no other components interposed therebetween.

Hereinafter, embodiments of the present invention will be described with reference to the drawings schematically showing ideal embodiments of the present invention. In the drawings, for example, depending on manufacturing techniques and/or tolerances, variations of the illustrated shape can be expected. Accordingly, the embodiments of the inventive concept should not be construed as being limited to the specific shape of the region shown in the present specification, but should include, for example, a change in shape caused by manufacturing. In addition, in the drawings, the thickness or size of each layer may be exaggerated for convenience and clarity of description. Identical symbols refer to the same elements.

The plasma referred to herein may be formed by a direct plasma method or a remote plasma method.

In the direct plasma method, for example, by supplying a reaction gas, a stress control gas and/or a post-processing gas to a processing space between an electrode and a substrate and applying high-frequency power, the reaction gas, the stress control gas and/or It includes a method in which plasma of the processing gas is directly formed in the processing space inside the chamber.

The remote plasma method includes, for example, a method of activating plasma of the reaction gas, stress control gas, and/or post-processing gas in a remote plasma generator and introducing it into the chamber. It can have the advantage of less damage to internal components and reduction of particle generation.

Meanwhile, in addition to this, the plasma referred to herein may be formed in a showerhead disposed on a substrate. In this case, the material in the plasma state may be provided to the processing space on the substrate through, for example, a spray hole formed in the showerhead.

Meanwhile, in the present specification, argon gas is described as an exemplary gas of an inert gas, but in the technical idea of the present invention, the argon gas is an inert gas such as helium (He), neon (Ne), argon (Ar), and krypton (Kr). ), xenon (Xe), and radon (Rn) may be replaced with a gas containing at least one or more.

1 is a flow chart illustrating a unit cycle of an atomic layer deposition process in a method of manufacturing a nitride film according to the technical idea of the present invention.

Referring to FIG. 1, a method of manufacturing a nitride film according to the technical idea of the present invention is a unit cycle including a first step (S110), a second step (S120), a third step (S130), and a fourth step (S140). This is a method of forming a nitride film having compressive stress on a substrate by performing (S100) at least once.

The nitride film may be understood as a nitride film formed by atomic layer deposition (ALD) in which a source gas, a purge gas, a reaction gas, and the like are provided on a substrate in a time division method or a space division method. The technical idea of the present invention is not only a time-division method in which deposition is implemented by supplying a source gas and a reaction gas discontinuously with time in a chamber in which a substrate is disposed, as well as a source gas and a reaction gas, etc. It can also be applied to a space division method in which deposition is implemented by sequentially moving the substrate in the supplied system.

In the first step (S110), at least a part of the source gas may be adsorbed on the substrate by providing the source gas on the substrate disposed in the chamber. The substrate may include, for example, a semiconductor substrate, a conductor substrate, an insulator substrate, and the like, and optionally, prior to forming the nitride film having the compressive stress, an arbitrary pattern or layer is formed on the substrate. It may already be formed. The adsorption may include chemical adsorption, which is widely known in atomic layer deposition.

The source gas may be appropriately selected according to the type of nitride film to be formed.

For example, when the nitride film to be formed is a silicon nitride film, the source gas is silane, disilane, trimethylsilyl (TMS), tris (dimethylamino) silane (TDMAS), bis (tertiary-butylamino) silane (BTBAS). ) And at least one selected from the group consisting of dichlorosilane (DCS).

In addition, for example, when the nitride film to be formed is a titanium nitride film, the source gas is from the group consisting of TDMAT (Tetrakis (dimethylamino) titanium), TEMAT (Tetrakis (ethylmethylamino) titanium), and TDETAT (Tetrakis (diethylamino) titanium). It may include at least one selected.

In addition, for example, when the nitride film to be formed is a tantalum nitride film, the source gas is Ta[N(CH ₃ ) ₂ ] ₅ , Ta[N(C ₂ H ₅ ) ₂ ] ₅ , Ta(OC ₂ H ₅₎ ) ₅ and Ta (OCH ₃ ) ₅ may include at least one selected from the group consisting of.

Of course, the types of the nitride film and the source gas described above are exemplary, and the technical idea of the present invention is not limited to these exemplary types of materials.

In the second step (S120 ), a first purge gas may be provided on the substrate. The first purge gas may remove at least a portion of the source gas except for a portion adsorbed on the substrate from the substrate.

That is, in the second step S120, the source gas not adsorbed on the substrate may be purged by the first purge gas. The first purge gas may be nitrogen gas, inert gas, or a mixed gas consisting of nitrogen gas and inert gas. The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

The unit cycle includes a step (S115) of stopping the supply of the source gas and maintaining a lower pressure in the chamber than in the first step (S115) after the first step (S110) and before the second step (S120). The pressure in the chamber in the step S115 may be lower than the pressure in the chamber in the first step S110, for example, by 10% to 90%.

By introducing the step (S115) between the first step (S110) and the second step (S120), the residue of the source gas remaining without being adsorbed on the substrate can be more effectively removed, thereby having relatively excellent quality The nitride of can be deposited. In particular, when the structure on the substrate on which the nitride is deposited is a stepped structure having a large aspect ratio, the effect of improving the nitride deposition step coverage by the step S115 may be more remarkable.

For example, the step (S115) may be implemented by stopping the supply of the source gas but performing pumping in the chamber. More specifically, the step S115 may be understood as a step in which only pumping is performed in a state in which the source gas, reaction gas, purge gas, and post-processing gas in the chamber are not supplied.

Meanwhile, the pumping performed in step S115 may be always performed throughout the unit cycle. For example, the pumping in the chamber will be continuously performed during the first step (S110), step (S115), second step (S120), third step (S130), and fourth step (S140) constituting a unit cycle. I can.

In the step 3 (S130) to the substrate simultaneously or sequentially and the reaction gas containing nitrogen (N) outside the stress control gas and the nitrogen gas (N ₂₎ having a nitrogen gas (N ₂₎ into a plasma state By providing a unit deposition film on the substrate can be formed.

The unit deposition layer is a thin film constituting the nitride layer to be formed. For example, when the unit cycle S100 is repeated N times (N is a positive integer greater than 1), the finally formed nitride layer is N It may be composed of the unit deposition film.

The stress control gas is a gas provided to control the stress of the unit deposition film, that is, finally the stress of the nitride film, and the present inventor provides a stress control gas including nitrogen gas (N ₂ ) in the third step (S130). When provided, it was confirmed that the stress of the nitride film can be effectively controlled.

For example, in the third step, the amount of compressive stress of the nitride film may be adjusted by adjusting the amount of nitrogen gas (N ₂ ) provided on the substrate and constituting the stress control gas. Specifically, in the third step, it was confirmed that the greater the amount of nitrogen gas (N ₂ ) provided on the substrate and constituting the stress control gas, the greater the compressive stress can be implemented. .

While nitrogen gas (N ₂ ) has a non-polar covalent bond and has stability when it exists as a non-polar covalent bond, for example, in the third step (S130), nitrogen gas (N ₂ ) is N ₂ ⁺ And/or N ⁺ is ionized. At this time, the ionization energy of N ₂ ⁺ and/or N ⁺ is very large, and in order to exist in a more stable form, for example, when the nitride film to be formed is a silicon nitride film, Si-N bonds occur. At this time, it is understood that a strong bond with Si occurs due to strong ionization energy, and a strong compressive stress occurs.

Meanwhile, a reaction gas containing a nitrogen component (N) may chemically react with the source gas adsorbed on the substrate to form a unit deposition film constituting a nitride film. Here, the nitrogen component (N) constituting the reaction gas refers to a nitrogen component excluding the nitrogen gas (N ₂ ) constituting the stress control gas. For example, the reaction gas containing the nitrogen component (N) may include ammonia (NH ₃ ) gas.

The plasma referred to herein may be formed by a direct plasma method or a remote plasma method.

In the direct plasma method, for example, by supplying the reaction gas and the stress control gas to the processing space between the electrode and the substrate and applying high frequency power, the plasma of the reaction gas and the stress control gas is reduced to the inside of the chamber. It includes a method that is formed directly in the processing space.

The remote plasma method includes, for example, a method of activating the plasma of the reaction gas and the stress control gas in a remote plasma generator and introducing it into the chamber, and damage to internal components such as electrodes is less than that of direct plasma. It can have the advantage that it is small and particle generation can be reduced.

Meanwhile, in addition to this, the plasma referred to herein may be formed in a showerhead disposed on a substrate. In this case, the material in the plasma state may be provided to the processing space on the substrate through, for example, a spray hole formed in the showerhead.

In the fourth step (S140), a second purge gas may be provided on the substrate. The second purge gas may physically and/or chemically react with the source gas adsorbed on the substrate and remove at least a portion of the stress control gas and the reaction gas remaining on the substrate from the substrate.

That is, in the fourth step (S140), at least a portion of the stress control gas and the reaction gas, which reacts physically and/or chemically with the source gas adsorbed on the substrate and remains on the substrate, is a second purge gas It can be purged by.

The second purge gas may be nitrogen gas, inert gas, or a mixed gas consisting of nitrogen gas and inert gas. The inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

The technical features of the present invention relates to a method for controlling the stress of the nitride film in the step of forming the nitride film by atomic layer deposition method, a nitrogen other stress control gas and the nitrogen gas (N ₂₎ having a nitrogen gas (N ₂₎ A nitride film having compressive stress is formed on the substrate by performing at least one unit cycle including the step of simultaneously providing a reaction gas containing component (N) on the substrate in a plasma state, wherein the compressive stress is Is that it can be controlled by adjusting the amount of the nitrogen gas (N ₂ ).

FIG. 2 is a diagram illustrating sequentially from left to right a series of processes that a substrate undergoes over time during a unit cycle in a method of manufacturing a nitride film according to an embodiment of the present invention. This embodiment may refer to the manufacturing method of FIG. 1, and thus, a duplicate description is omitted.

First, referring to FIG. 2, only a unit cycle including a first step (S110), a pumping-only step (S115), a second step (S120), a third step (S130), and a fourth step (S140) By repeatedly performing at least one or more times, a nitride film may be implemented.

The pumping performed in step S115 may also be performed in the first step (S110), the second step (S120), the third step (S130), and the fourth step (S140), but the step of performing only the pumping (S115) ) Is to be understood as a step in which only the pumping is performed in a state in which the source gas, stress control gas, reaction gas, purge gas, etc. are not supplied in the chamber.

Referring to FIG. 2, for example, at least one of the first purge gas in the second step S120 and the second purge gas in the fourth step S140 may include nitrogen gas N ₂ . The reaction gas in the third step (S130) includes ammonia (NH ₃ ) gas, and the stress control gas may include nitrogen gas (N ₂ ).

2, for another example, at least one of the first purge gas in the second step (S120) and the second purge gas in the fourth step (S140) includes argon gas (Ar), which is an inert gas. can do. The reaction gas in the third step (S130) includes ammonia (NH ₃ ) gas, and the stress control gas may include nitrogen gas (N ₂ ).

Referring to Figure 2, for another example, at least one of the first purge gas in the second step (S120) and the second purge gas in the fourth step (S140) is nitrogen gas (N ₂ ) and argon gas It may be a mixed gas containing (Ar). The reaction gas in the third step (S130) includes ammonia (NH ₃ ) gas, and the stress control gas may include nitrogen gas (N ₂ ) and argon gas (Ar).

On the other hand, the present inventors believe that the higher the relative ratio of nitrogen gas (N ₂ ) to argon gas (Ar) in the stress control gas of the third step (S130), the greater the compressive stress of the finally implemented nitride film becomes, and It was confirmed that the higher the relative ratio of argon gas (Ar) to nitrogen gas (N ₂ ) in the stress control gas of step S130, the smaller the compressive stress of the finally implemented nitride film was.

Therefore, when the stress control gas contains nitrogen gas (N ₂ ) and argon gas (Ar), the nitride film is formed by adjusting the relative ratio of nitrogen gas (N ₂ ) to argon gas (Ar) in the third step (S130). It can be expected that the compressive stress of can be easily and precisely controlled.

FIG. 3 is a diagram illustrating a series of processes sequentially from left to right by a substrate over time during a unit cycle in a method of manufacturing a nitride film according to another embodiment of the present invention.

Referring to FIG. 3, at least one unit cycle including a first step (S110), only performing pumping (S115), a second step (S120), a third step (S130), and a fourth step (S140) The nitride film can be implemented by repeating it more than once. The description of the step of performing only pumping (S115) is substantially the same as the contents mentioned with reference to FIG. 2, and thus will be omitted herein.

3, the first purge gas provided in the second step (S120) or the second purge gas provided in the fourth step (S140) is continuously in the first step (S110) to the fourth step (S140). Can be supplied. That is, the first purge gas or the second purge gas may be provided on the substrate in the first step (S110), and the first purge gas or the second purge gas may be provided on the substrate in the third step (S110). have.

The purge gas provided in the first step (S110) may serve as a carrier of the source gas, and the source gas may be evenly distributed and adsorbed on the substrate.

Likewise, the purge gas provided in the third step (S130) may serve as a carrier so that the reaction gas and the stress control gas are evenly distributed and adsorbed on the substrate.

On the other hand, in the method of manufacturing a nitride film according to a modified embodiment of the present invention, performing the first unit cycle shown in FIG. 2 at least once and performing the second unit cycle shown in FIG. 3 at least once It can contain all steps. The arrangement order and the number of repetitions of the first unit cycle and the second unit cycle may be appropriately designed according to the required characteristics of the nitride film.

4 is a flowchart illustrating a unit cycle of an atomic layer deposition process in a modified manufacturing method of a nitride film according to another technical idea of the present invention. This manufacturing method may refer to the manufacturing method described in FIG. 1, and thus, a duplicate description is omitted. That is, the present manufacturing method is different from that of the manufacturing method described in FIG. 1 in that step S135 is added, and therefore, the remaining steps are redundant and thus description thereof will be omitted.

Referring to FIG. 4, after the third step (S130) and before the fourth step (S140), the provision of the stress control gas and the reaction gas in the chamber is stopped, and the pressure in the chamber is lowered than in the third step. It includes the step of maintaining (S135). The pressure in the chamber in the step S135 may be lower than the pressure in the chamber in the third step S130, for example, by 10% to 90%.

By introducing the step (S135) between the third step (S130) and the fourth step (S140), the residue of the reaction gas remaining without reacting with the source gas adsorbed on the substrate and the residue of the stress control gas This can be removed more effectively, whereby a relatively good quality nitride can be deposited. Particularly, when the structure on the substrate on which the nitride is deposited is a stepped structure having a large aspect ratio, the effect of improving the nitride deposition step coverage by the step S135 may be more remarkable.

For example, the step (S135) may be implemented by stopping the provision of the stress control gas and the reaction gas, but performing pumping in the chamber. More specifically, the step (S135) may be understood as a step in which only pumping is performed in a state in which the source gas, the stress control gas, the reaction gas, the purge gas, etc. are not supplied in the chamber.

On the other hand, steps (S115) and (S135) of configuring the unit cycle are the same in that only pumping is performed without supplying any gas in the chamber, but according to the specific process sequence applied, the steps ( S115) is a step in which the supply of the source gas is stopped and the chamber is pumped, and the step (S135) can be distinguished in that the supply of the stress control gas and the reaction gas is stopped and the chamber is pumped.

Meanwhile, chamber pumping may be performed at all times throughout the unit cycle as well as in the step S135. For example, the pumping in the chamber comprises a first step (S110), the above-described step (S115), a second step (S120), a third step (S130), the above-described step (S135), and It may be performed continuously during step S140.

On the other hand, although not separately shown in the drawings, in another modified manufacturing method of the nitride film according to the technical idea of the present invention, the unit cycle for forming the nitride film is, after the fourth step (S140), the second on the unit deposition film. A fifth step (S150) of providing the stress control gas in a plasma state and a sixth step (S160) of providing a third purge gas on the substrate may be further included. In this case, in order to distinguish the stress control gas in the third step (S130) and the fifth step (S150) for convenience, the stress control gas of the third step (S130) is named as the first stress control gas, and the fifth step The stress control gas of (S150) may be referred to as a second stress control gas.

The second stress control gas may include nitrogen gas (N ₂ ). For example, the second stress control gas may be composed of only nitrogen gas (N ₂ ).

Alternatively, the second stress control gas may include a mixed gas of an inert gas and a nitrogen gas (N ₂ ). Here, the inert gas may include at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).

In the fifth step (S150), by providing the second stress control gas on the substrate in a plasma state, the first step (S110) to the fourth step (S140) are performed to determine a predetermined film quality of the unit deposition film. The stress distribution can be implemented more precisely.

The nitrogen gas (N ₂ ) disclosed in the third step (S130) is simultaneously provided on the substrate together with the reaction gas, but the nitrogen gas (N ₂ ) disclosed in the fifth step (S150) reacts after purging the reaction gas. It is distinguished in that it is provided on the substrate separately from the gas.

In the sixth step (S160), a third purge gas may be provided on the substrate. The third purge gas may remove at least a portion of the nitrogen gas N ₂ provided in the fifth step S150 from the substrate.

That is, in the sixth step (S160), at least a part of the second stress control gas provided in the fifth step (S150) may be purged by the third purge gas. The third purge gas may be nitrogen gas, argon gas, or a mixed gas consisting of nitrogen gas and argon gas.

In the present inventors, the higher the relative ratio of nitrogen gas (N ₂ ) to argon gas (Ar) among the stress control gas composed of nitrogen gas (N ₂ ) and argon gas (Ar), the finally realized compressive stress of the nitride film Was confirmed to be larger. On the other hand, in the method of manufacturing a nitride film according to an exemplary embodiment of the present invention, it can be seen that the wet etch rate ratio (WERR) representing the film quality of the nitride film does not have a relatively large variation even though the compressive stress of the nitride film increases. In contrast, in the comparative example of the present invention in which a nitride film is formed without using a stress control gas including nitrogen gas (N ₂ ), the compressive stress of the nitride film can be increased by increasing the plasma power, but at the same time, the film quality of the nitride film is expressed. It was confirmed that the wet etching rate ratio (WERR) had relatively large fluctuations.

In this case, in order to control the stress of the nitride film, the power (or frequency) of the power source for forming the plasma within a unit cycle of the atomic layer deposition process can be adjusted, but in this case, the film quality of the nitride film changes according to the plasma power or frequency. Suggests that is relatively large.

On the contrary, according to an embodiment of the present invention, the stress of the nitride film can be adjusted by adjusting the mixing ratio of nitrogen gas (N ₂ ) and argon gas (Ar) during plasma formation within a unit cycle of the atomic layer deposition process. In this case, It can be seen that the film quality of the nitride film can be maintained at a relatively same level regardless of the stress of the nitride film.

Further, in a modified embodiment of the present invention, as a method for controlling the stress of the nitride film, forming the plasma at the same time as controlling the ratio of nitrogen gas (N ₂ ) during plasma formation within a unit cycle of the atomic layer deposition process. It is possible to additionally adjust the frequency or power (also called plasma power or frequency) of the power applied for the purpose. According to this modified embodiment, it is possible to expect an effect that the compressive stress range of the nitride film can be more widely adjusted while maintaining good film quality of the nitride film.

For example, if the compressive stress of the nitride film is required to be very high, plasma damage may occur on the surface of the nitride film when the nitride film is deposited by controlling the frequency or power of the plasma, but the flow rate of nitrogen gas (N ₂ ) When the nitride film is deposited by additionally adjusting the frequency or power of the plasma while controlling the plasma, it is advantageous in that a very high compressive stress can be realized without plasma damage to the surface of the nitride film.

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely exemplary, and those of ordinary skill in the art will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims (12)

A first step of providing a source gas on a substrate disposed in the chamber to adsorb at least a portion of the source gas on the substrate;
A second step of providing a first purge gas on the substrate;
To provide a reaction gas containing nitrogen (N) outside the stress control gas and the nitrogen gas (N ₂₎ having a nitrogen gas (N ₂₎ on the substrate to a plasma state to form a unit deposition film on the substrate The third step;
A fourth step of providing a second purge gas on the substrate; And
After the first step and before the second step, stopping the supply of the source gas and maintaining the pressure in the chamber lower than in the first step;
A nitride film having compressive stress is formed on the substrate by performing at least one unit cycle including,
The stress control gas and the reaction gas are different from each other,
Characterized in that the stress of the nitride film is controlled by adjusting the amount of the stress control gas in the third step,
Method for producing a nitride film. The method of claim 1,
The step of maintaining the pressure in the chamber lower than in the first step is implemented by stopping the supply of the source gas but performing pumping in the chamber. The method of claim 2,
The pumping is always performed throughout the unit cycle, a method of manufacturing a nitride film. The method of claim 1,
The unit cycle is
After the third step and before the fourth step, the step of stopping the supply of the stress control gas and the reaction gas and maintaining the pressure in the chamber lower than that in the third step; comprising, a method of manufacturing a nitride film. The method of claim 4,
The step of maintaining the pressure in the chamber lower than in the third step is implemented by stopping the supply of the stress control gas and the reaction gas, but performing pumping in the chamber. The method of claim 5,
The pumping is always performed throughout the unit cycle, a method of manufacturing a nitride film. The method according to any one of claims 1 to 6,
The method of manufacturing a nitride film, in which the amount of the nitrogen gas (N ₂ ) provided on the substrate in the third step is increased as the required compressive stress of the nitride film is increased. The method according to any one of claims 1 to 6,
The stress control gas includes a mixed gas of an inert gas and the nitrogen gas (N ₂ ), a method of manufacturing a nitride film. The method of claim 8,
The inert gas includes at least one of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). The method of claim 9,
In the third step, as the required compressive stress of the nitride film increases, the relative ratio of the nitrogen gas (N ₂ ) to the inert gas provided on the substrate is increased. The method according to any one of claims 1 to 6,
The stress control gas is the same gas as at least one of the first purge gas and the second purge gas, a method of manufacturing a nitride film. The method according to any one of claims 1 to 6,
The plasma is a direct plasma method or remote plasma.
A method of manufacturing a nitride film formed by a remote plasma method.

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