Method for etching silicon-containing film, and methods for producing semiconductor and display devices including same

Abstract

The present invention relates to a method for etching a silicon-containing film and, more particularly, to a method for etching a silicon-containing film using an FNO-containing etching gas via chemical plasma etching, and methods for producing semiconductor and display devices including the etching method.

Description

Method for etching a silicon-containing film and method for manufacturing a semiconductor and display device including the same

[0001] The present invention relates to a method for etching a silicon-containing film, and more specifically, to a method for etching a silicon-containing film using an etching gas containing FNO through a chemical plasma etching method, and a method for manufacturing a semiconductor and display device including the same.

[0002] Generally, a series of processes such as deposition, etching, ion implantation, and cleaning are performed to manufacture semiconductor or display devices. These processes are carried out in a process chamber capable of maintaining process conditions, under various process conditions such as atmospheric pressure, low pressure, and vacuum. Among these, the etching process is a process that selectively removes a portion of a thin film formed on a substrate by a deposition process to form an ultrafine structure (pattern, etc.) of a desired shape.

[0003] Etching processes, particularly dry etching processes, remove part or all of a thin film by injecting etching gas in a gaseous state and causing the injected etching gas to react with an etching target (e.g., a silicon-containing film) on a substrate to form volatile byproducts. As a method for dry etching processes, plasma etching methods are mainly used, which utilize active ions or plasma to increase the reactivity between the etching gas and the etching target. Plasma etching is a method in which the etching gas is plasmafied to form highly reactive radicals and ions, and these active species (Radicals) and ions (Ions) physically or chemically etch the etching target.

[0004] The etching gas for dry etching is an active ion or plasma, for example, Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Remote Plasma System (RPS), plasma by Electron Cyclotron Resonance (ECR), Transformer Coupled Plasma (TCP) method, High Density Plasma (HDP), Reactive Ion, Magnetically Enhanced Reactive Ion, etc.

[0005] Direct plasma technology can be used for plasmafication of the etching gas. Direct plasma technology is a method in which plasma generated by directly applying power to a process chamber, such as CCP (Capacitively Coupled Plasma) or ICP (Inductively Coupled Plasma), comes into direct contact with the substrate and the etching target. At this time, inert gases such as helium (He) and argon (Ar) are mixed and injected to aid in plasmafication of the etching gas and to accelerate physical etching.

[0006] In addition, remote plasma technology can be used for plasmafication of the etching gas. Remote plasma technology is a method in which the plasma generator is separated from the chamber, using a device that generates plasma in an isolated vessel and uses the plasma diffused into the reaction vessel, or using a plasma device generated from such a device. In this case as well, inert gases such as helium (He) and argon (Ar) can be mixed and injected to help plasmaficate the cleaning gas and accelerate physical etching.

[0007] In the etching process, to form ultrafine structures of a desired shape, the etching target must have a high etch rate, while the thin film not to be etched must have a low etch rate. The ratio of the etch rate of the thin film to be etched to the etch rate of the thin film not to be etched is called selectivity, and a reaction gas with a high selectivity is required for the etching process. In particular, recently, it has become necessary to develop reaction gases with even higher selectivity in order to manufacture semiconductor devices capable of miniaturization or high integration.

[0008] Perfluorocompound gases such as CF4, C3F6, SF6, and NF3 have been widely used as conventional reaction gases. However, conventional perfluorocompound reaction gases present difficulties in treating waste gases emitted after the etching process, requiring high treatment costs before being released into the atmosphere. Furthermore, conventional perfluorocompound gases have a very high Global Warming Potential (GWP) along with a long atmospheric lifetime, and are identified as a major factor in climate change.

[0009] Accordingly, there is a demand for alternative reaction gases that have a low global warming potential and excellent etching performance, particularly selectivity, for silicon-containing films.

[0010] The present invention aims to solve the problems of the prior art and to provide an etching method for a silicon-containing film that uses an environmentally friendly reaction gas that has a low global warming potential and allows for water scrubbing, thereby facilitating post-processing, by replacing the conventional reaction gas containing perfluoro compound gas with a dry etching method.

[0011] In addition, the present invention aims to provide a method for etching a silicon-containing film with high selectivity by activating an etching gas into a plasma that further includes an inert gas that assists in the generation of plasma and performs physical etching, along with a reaction gas.

[0012] In addition, the present invention aims to provide a method for manufacturing a semiconductor device and a display device comprising a method for etching the silicon-containing film.

[0013] The objectives of the present invention are not limited to those mentioned above, and other objectives and advantages of the present invention not mentioned may be understood from the following description and will be more clearly understood from the experimental examples of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0014] To achieve the above objective, a method for etching a silicon-containing film according to one embodiment of the present invention may include: (S1) introducing a substrate comprising a first silicon-containing film and a second silicon-containing film into a process chamber of an etching apparatus; (S2) supplying an etching gas comprising a reaction gas to the process chamber; (S3) forming a radical of the etching gas within the process chamber maintained at a predetermined pressure and power; and (S4) etching the first silicon-containing film on the substrate by the radical of the etching gas, wherein the reaction gas may include FNO gas, and forming the radical of the etching gas may be performed by a Remote Plasma System (RPS) method.

[0015] A method for manufacturing a semiconductor device or a display device according to another embodiment of the present invention may include a method for etching a silicon-containing film according to the above embodiment of the present invention.

[0016] According to the etching method of the silicon-containing film of the present invention, the etching gas containing FNO is environmentally friendly as it has a low global warming potential, and can significantly improve the etch rate of the silicon-containing film, while at the same time increasing the etching selectivity ratio of the silicon nitride film to the silicon oxide film.

[0017] In addition, according to the etching method of the silicon-containing film of the present invention, the etching gas containing FNO is capable of water scrubbing, making it easy for post-processing, and has excellent eco-friendliness and process efficiency.

[0018] In addition to the effects described above, the effects of the present invention are described together with the details for implementing the invention below.

[0019] The aforementioned objectives, features, and advantages are described in detail below with reference to this specification, and accordingly, a person skilled in the art to which the present invention pertains will be able to easily implement the technical concept of the present invention. In describing the present invention, detailed descriptions of known technologies related to the present invention are omitted if it is determined that such descriptions may unnecessarily obscure the essence of the present invention.

[0020] In describing this specification, if it is determined that a detailed description of related prior art could unnecessarily obscure the gist of this specification, such detailed description is omitted.

[0021] Where terms such as “comprising,” “having,” “consisting of,” “arranging,” or “having” are used for a component in this specification, other parts may be added unless “only” is used. Where a component is expressed in the singular, it includes cases where it is included in the plural unless specifically stated otherwise.

[0022] In interpreting the components in this specification, they are interpreted to include an error range even if there is no separate explicit description.

[0023] The present invention will be described in detail below.

[0024] According to the present invention, the method comprises: (S1) introducing a substrate including a first silicon-containing film and a second silicon-containing film into a process chamber of an etching apparatus; (S2) supplying an etching gas including a reaction gas to the process chamber; (S3) forming a radical of the etching gas within the process chamber maintained at a predetermined pressure and power; and (S4) etching the first silicon-containing film on the substrate by the radical of the etching gas, wherein the reaction gas includes FNO gas, and forming the radical of the etching gas can be performed by a Remote Plasma System (RPS) method.

[0025] The present invention relates to a method for etching silicon-containing films, wherein an environmentally friendly etching process can be performed by using FNO instead of NF3, which has been conventionally used as a reaction gas. In particular, the invention adopts a method for etching silicon-containing films that includes FNO gas as a reaction gas, and is characterized by etching by forming active species through chemical etching, more preferably via a Remote Plasma System (RPS) method, rather than physical etching such as Capacitively Coupled Plasma (CCP). Since NO radicals are formed from the reaction gas FNO via RPS, the invention is not only environmentally friendly but also has the advantage of improving the etch rate for silicon oxide films and silicon nitride films and achieving a high etching selectivity ratio (SiN / SiO2 selectivity ratio).

[0026] According to one example, the first silicon-containing film may be a silicon nitride film, and the second silicon-containing film may be a silicon oxide film. However, the etching method of the present invention is not limited thereto and can be applied to etch other silicon-containing films listed above.

[0027] According to one example, the etching selectivity ratio (SiN / SiO2) of the first silicon-containing film to the second silicon-containing film may be 15 or more, preferably 17 or more, more preferably 18 or more, even more preferably 19 or more, and most preferably 20 or more.

[0028] According to one example, the etch rate of the silicon oxide film may be 15 nm / min or more, 30 nm / min or more, 40 nm / min or more, 50 nm / min or more, 60 nm / min or more, 70 nm / min or more, 80 nm / min or more, 90 nm / min or more, 100 nm / min or more, 110 nm / min or more, 120 nm / min or more, 130 nm / min or more, 140 nm / min or more, and since it is important to improve the etching selectivity, there is no specific upper limit, but for example, the etch rate of the silicon oxide film may be 160 nm / min or less, for example, 150 nm / min or less.

[0029] According to one example, the etch rate of the silicon nitride film may be 500 nm / min or higher, 1000 nm / min or higher, 1500 nm / min or higher, 1700 nm / min or higher, 1800 nm / min or higher, 2000 nm / min or higher, 2100 nm / min or higher, and since it is important to improve the etching selectivity, there is no specific upper limit, but for example, the etch rate of the silicon nitride film may be 2500 nm / min or lower, for example, 2200 nm / min or lower.

[0030] According to one example, the flow rate of the FNO gas may be 300 sccm to 3000 sccm, for example, 700 sccm to 2000 sccm, but is not limited thereto and may be changed according to process conditions and requirements. If the flow rate of the FNO gas is below the lower limit, the etch rate for the silicon oxide film and silicon nitride film may not reach the level intended in the present invention, and if it exceeds the upper limit, the power of the plasma system (e.g., RPS) becomes excessively high, which may result in a problem of reduced efficiency.

[0031] According to one example, the etching gas may further include an inert gas comprising one or more of argon (Ar), helium (He), krypton (Kr), and neon (Ne). By including the inert gas in this way, plasma can be efficiently formed within a plasma system (e.g., RPS), and as a result, an active species F originating from the FNO gas can be efficiently transported into a reaction chamber, thereby making it easier to etch silicon oxide films and silicon nitride films.

[0032] According to one example, the flow rate of the inert gas may be 500 sccm to 2500 sccm, for example, 500 sccm to 1500 sccm, but is not limited thereto and may be changed according to process conditions and requirements. If the flow rate of the inert gas is below the lower limit, it may not be possible to efficiently form plasma with FNO gas within a plasma system (e.g., RPS) to form the active species F, and if it exceeds the upper limit, the active species F may be diluted, which may lower the etch rate of the silicon oxide film and silicon nitride film within the chamber. According to one example, the value of Equation 1 below, which is the ratio to the flow rates of the reaction gas and the inert gas, may be controlled within a range of 15 to 90%, for example, within a range of 25 to 50%. If it falls outside the above range, there may be problems such as the etch rate of the silicon oxide film and silicon nitride film being significantly lowered or it being difficult to create an environment for the plasma system.

[0033] <Equation 1> {(Reaction gas flow rate) / (Reaction gas flow rate + Inert gas flow rate)} × 100(%)

[0034] According to one example, the etching gas may further include additive gases (H2, O2, N2, etc.), such as hydrogen, oxygen, and nitrogen, depending on the etching target or the etching process. The ratio of the reactive gas to the inert gas can be adjusted according to the added additive gas.

[0035] According to one example, the above-mentioned predetermined pressure can be controlled within a range of 400 mTorr to 5,000 mTorr, for example, within a range of 500 mTorr to 4,000 mTorr, or for example, within a range of 1,000 mTorr to 3,000 mTorr. If the pressure is outside this range, there may be problems such as the etch rate of the silicon oxide film and silicon nitride film being significantly lowered, side reactions occurring, or deposition occurring instead of etching. When the etching gas is supplied to the process chamber, a device such as a vacuum system can be used to maintain the pressure inside the process chamber at an appropriate pressure condition.

[0036] In addition, if necessary, the temperature of the substrate can be maintained at an appropriate temperature condition through a heater and a cooling water channel within the substrate holder, but according to one example, the temperature condition within the chamber may be room temperature, for example, 15 to 25°C, or for example, 18 to 20°C.

[0037] Next, plasma is generated within the process chamber by applying a predetermined power to the etching device under appropriate pressure and temperature conditions. Active species and ions generated within the plasma chemically react with the substrate to etch the silicon-containing film formed on the substrate. During the etching step, the plasma can be maintained for an appropriate amount of time to form a desired ultrafine structure on the substrate.

[0038] According to one example, the above-mentioned power can be controlled within a range of 1 kW to 10 kW, for example, within a range of 1 kW to 8 kW, and within a range of 2 kW to 6 kW. If the power is outside the above range, there may be problems such as the etch rate of the silicon oxide film and silicon nitride film being significantly lowered, side reactions occurring, or adverse effects on the durability of the plasma generating device.

[0039] The structure and operation of the present invention will be explained in more detail below through preferred experimental examples. However, these are presented as preferred examples of the present invention and should not be interpreted in any way as limiting the present invention.

[0040] <Experimental Example 1>

[0041] A substrate comprising a silicon nitride film (SiN) as the first silicon-containing film and a silicon oxide film (SiO2) as the second silicon-containing film was introduced into the process chamber of an etching device.

[0042] Then, an etching gas containing FNO gas as a reaction gas and argon (Ar) gas as an inert gas was supplied to the process chamber, and active species of the etching gas were formed within the process chamber using a Remote Plasma System (RPS) method. The results of experiments conducted while fixing the FNO gas flow rate at 500 sccm and varying the Ar gas flow rate from 500 sccm to 1,500 sccm are shown in Table 1 below. The results of experiments conducted while fixing the Ar gas flow rate at 1,000 sccm and varying the FNO gas flow rate from 300 sccm to 700 sccm are shown in Table 2 below. In each experiment, the pressure inside the process chamber was approximately 2 Torr and the temperature was approximately 20°C. The ratio of the flow rates of the reaction gas and inert gas in each experiment was calculated according to Equation 1 below (the calculated values ​​were rounded to the second decimal place), and the RPS power conditions, the etch rate of the first silicon-containing film (SiN) and the second silicon-containing film (SiO2), and the etch selectivity ratio (SiN / SiO2) were calculated, and the results are shown in Tables 1 and 2 below, respectively.

[0043] <Equation 1> {(Reaction gas flow rate) / (Reaction gas flow rate + Inert gas flow rate)} × 100(%)

[0044] FNO Flow Rate: 500 sccm Ar Flow Rate (sccm) Value of Equation 1 RPS Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Experimental Example 1-1 500 50 % 58 50 38.18 49.4 22.29 Experimental Example 1-2 1000 33.3 % 54 00 36.76 93.6 18.90 Experimental Example 1-3 1500 25 % 49 60 32.75 66.7 17.33

[0045] Ar Flow Rate: 1000 sccm FNO Flow Rate (sccm) Value of Equation 1 RPS Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Experimental Example 1-4 300 23.1 % 44 50 27.5 5 40.3 22.29 Experimental Example 1-5 500 33.3 % 53 70 36.7 6 93.6 18.90 Experimental Example 1-6 700 41.2 % 59 50 42.6 828.6 17.33

[0046] As can be seen in Tables 1 and 2 above, when etching is performed under high power using RPS, the etch rates of the silicon oxide film and silicon nitride film, respectively, were significantly high when the flow rates and ratios of the reaction gas and inert gas intended in the present invention were within the range, and the etch selectivity ratio of the silicon nitride film to the silicon oxide film was also excellent. Specifically, referring to Tables 1 and 2, as the applied power of the RPS increases, the dissociation rate of the reaction gas, FNO gas, increases, and the amount of F active species generated increases; consequently, the etch rates of the silicon oxide film and silicon nitride film each increase, and the etch selectivity ratio also showed a high level of 15 or higher, preferably 17 or higher, more preferably 18 or higher, even more preferably 19 or higher, and most preferably 20 or higher.

[0047] <Experimental Example 2>

[0048] A substrate containing a silicon oxide film (SiO2) as a silicon-containing film was introduced into the process chamber of an etching apparatus. Then, experiments were conducted by varying the flow rates of FNO gas, an etching gas, as the reaction gas, and Ar gas, an inert gas, in the process chamber as shown in Table 3 below. The pressure inside the process chamber was 3 Torr and the temperature was approximately 18°C. The ratio of the flow rates of the reaction gas and inert gas in each experiment was calculated according to Equation 1 below (calculated values ​​were rounded to the second decimal place), and the RPS power conditions, pressure conditions, and the etch rate of the silicon oxide film (SiO2) are shown in Tables 3 and 4 below, respectively.

[0049] Ar Flow Rate: 500 sccm FNO Flow Rate (sccm) Ar Flow Rate (sccm) Value of Equation 1 (%) RPS Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Experimental Example 2-1: 250 500 81.8 % 718 611 6.6 219 27.6 16.5 Experimental Example 2-2: 750 500 77.78 % 68 351 03.6 618 31.6 17.6 Experimental Example 2-3: 250 500 71.43 % 636 075.3 176 323.4 Experimental Example 2-4: 750 500 60 % 56 133 9.8 14 32.8 36

[0050] The sum of FNO flow rate and Ar flow rate is a total of 3000 sccm FNO Flow Rate (sccm) Ar Flow Rate (sccm) Value of Equation 1 (%) RPS Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Experimental Example 2-5 2250 750 75 % 70 10 10 9.0 8 17 84.8 16.25 Experimental Example 2-6 1250 1750 41.67 % 62 649 0.2 41 376.8 15.25 Experimental Example 2-7 1250 1750 41.67 % 53 20 67.9 41 12 916.62 Experimental Example 2-8 750 2250 25 % 40 234 3.7 254 0.6 12.36

[0051] <Experimental Example 3>

[0052] A substrate containing a silicon oxide film (SiO2) as a silicon-containing film was introduced into the process chamber of an etching device. Then, FNO gas, an etching gas, was supplied to the process chamber at a rate of 2,500 sccm as a reaction gas, and Ar gas was supplied as an inert gas at a rate of 500 sccm. The value calculated according to Equation 1 was 83.3%. The pressure inside the process chamber was varied as shown in Table 3 below, and the temperature was set to approximately 18°C. The ratio of the flow rates of the reaction gas and inert gas in each experiment was calculated according to Equation 1 below (the calculated values ​​were rounded to the second decimal place), and the RPS power conditions, pressure conditions, and the etch rate of the silicon oxide film (SiO2) are shown in Table 5 below.

[0053] Pressure (Torr) RPS Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Experimental Example 3-1 1.5 36 30 76.1 110 714.55 Experimental Example 3-2 27 220 10 8.5 160 514.79 Experimental Example 3-3 2.5 7 328 119 166 313.97 Experimental Example 3-4 37 35 41 21.3 17 80.8 14.68 Experimental Example 3-5 3.5 7 500 134.5 19 70 14.64 Experimental Example 3-6 47 65 51 43.1 420 41 14.25 Experimental Example 3-7 4.5 78 251 49.78 208 1.4 13.89 Experimental Example 3-857958146.48212314.49

[0054] <Experimental Example 4>

[0055] A substrate containing a silicon oxide film (SiO2) as a silicon-containing film was introduced into the process chamber of an etching apparatus. Then, an etching gas containing FNO gas and Ar gas as reaction gases was supplied to the process chamber at the flow rates shown in Table 6 below, and the temperature inside the process chamber was approximately 18°C. The ratio of the flow rates of the reaction gas and the inert gas in each silicon oxide film experiment was calculated according to Equation 1 below (the calculated values ​​were rounded to the second decimal place), and the pressure conditions inside the process chamber, RPS power conditions, and the etch rate of the silicon oxide film (SiO2) are respectively shown in Table 6 below.

[0056] FNO Flow Rate (sccm) Ar Flow Rate (sccm) Value of Equation 1 (%) Pressure (Torr) RPS Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Experimental Example 4-1 2500 500 83.3 % 272 20 10 8.5 160 514.79 Experimental Example 4-23 000 500 85.7 % 379 551 39.18 18 39.21 3.21 Experimental Example 4-3 25000 274 ​​871 24.8 167 6.61 3.43

[0057] Referring to Tables 3 to 6 above, it was experimentally confirmed that as the ratio of the FNO flow rate, the pressure inside the chamber, and the applied power of the RPS increase, the dissociation rate of the FNO gas, which is the reaction gas, increases, the amount of F active species produced increases, and consequently, the etch rate of the silicon oxide film increases.

[0058] <Comparative Experiment Example 1>

[0059] A substrate containing SiN as the first silicon-containing film and SiO2 as the second silicon-containing film was introduced into the process chamber of an etching device.

[0060] Then, an etching gas containing FNO gas as a reaction gas and argon (Ar) gas as an inert gas was supplied to the process chamber, and active species of the etching gas were formed within the process chamber using a remote Capacitively Coupled Plasma (CCP) method. The flow rate of the FNO gas was 40 sccm, and no inert gas was supplied. In each experiment, the pressure inside the process chamber was approximately 400 mTorr and the temperature was approximately 20°C, and the experiment was conducted while varying the power from 300 W to 500 W. The etch rate and etch selectivity ratio (SiN / SiO2) of the first silicon-containing film (SiN) and the second silicon-containing film (SiO2) were calculated, and the results are shown in Table 7 below.

[0061] Power (W) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Comparative Experiment Example 1-13 00 118.86 10 41.88.76 Comparative Experiment Example 1-24 00 228.71 48 3.86.29 Comparative Experiment Example 1-35 00 38 1.95 158 7.44.16

[0062] <Comparative Experiment Example 2>

[0063] A substrate containing SiN as the first silicon-containing film and SiO2 as the second silicon-containing film was introduced into the process chamber of an etching device.

[0064] Then, an etching gas containing FNO gas as a reaction gas and argon (Ar) gas as an inert gas was supplied to the process chamber, and active species of the etching gas were formed within the process chamber using a remote Capacitively Coupled Plasma (CCP) method. The flow rate of the FNO gas was 40 sccm, and no inert gas was supplied. In each experiment, the power applied to the process chamber was approximately 500 W and the temperature was approximately 20°C, and experiments were conducted while varying the pressure from 200 mTorr to 400 mTorr. The etch rate and etch selectivity ratio (SiN / SiO2) of the first silicon-containing film (SiN) and the second silicon-containing film (SiO2) were calculated, and the results are shown in Table 8 below.

[0065] Pressure (mTorr) Etching Rate (nm / min) Etching Selectivity (SiN / SiO2) SiO2SiN Comparative Experiment Example 2-1 200 16 1.4 10 79.6 6.89 Comparative Experiment Example 2-2 300 30 4.1 14 6 16.69 Comparative Experiment Example 2-3 400 38 1.9 5 15 8 7.4 4.16

[0066] <Comparative Experiment Example 2>

[0067] Referring to the results of the above experimental examples and comparative experimental examples, it was confirmed that while the CCP (Capacitively Coupled Plasma) method can exhibit a high etch rate for each silicon-containing film, including silicon oxide and silicon nitride films, there are limitations in increasing the etching selectivity of the silicon nitride film relative to the silicon oxide film. Although the CCP increases the etch rate for the silicon nitride film due to etching by chemical and physical reactions, the etching rate for the silicon oxide film is higher, resulting in a lower etching selectivity. On the other hand, the RPS (Remote Plasma System) satisfying the process conditions of the present invention had the effect of achieving the desired etch rate level while significantly increasing the etching selectivity of the silicon nitride film relative to the silicon oxide film. Therefore, it was confirmed that the etching method using the RPS method of the present invention is desirable for application in processes where increasing the etching selectivity is important.

[0068] Although the present invention has been described in more detail with reference to the experimental examples in this specification, this specification is not necessarily limited to the results of such experimental examples and may be modified in various ways within the scope of the technical concept of this specification. Accordingly, the experimental examples disclosed in this specification are intended to explain, not limit, the technical concept of this specification, and the scope of the technical concept of this specification is not limited by such experimental examples. Therefore, the experimental examples described above should be understood as illustrative in all respects and not restrictive. The scope of protection of this specification shall be interpreted by the claims, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of this specification.

Claims

1. (S1) A step of introducing a substrate comprising a first silicon-containing film and a second silicon-containing film into a process chamber of an etching device; (S2) A step of supplying an etching gas containing a reaction gas to the process chamber; (S3) A step of forming an active species (radical) of the etching gas within the process chamber maintained at a predetermined pressure and power; and (S4) A step of etching the first silicon-containing film on the substrate by an active species of the etching gas, and The above reaction gas includes FNO gas, and The formation of active species of the above etching gas is performed by a Remote Plasma System (RPS) method, Etching method of a silicon-containing film.

2. In Paragraph 1, The first silicon-containing film is a silicon nitride film, and the second silicon-containing film is a silicon oxide film. Etching method of a silicon-containing film.

3. In Paragraph 2, The etching selectivity ratio (SiN / SiO2) of the silicon nitride film to the silicon oxide film is 15 or higher, Etching method of a silicon-containing film.

4. In Paragraph 3, The etch rate of the above silicon oxide film is 15 nm / min or higher, Etching method of a silicon-containing film.

5. In Paragraph 3, The etch rate of the above silicon nitride film is 500 nm / min or higher, Etching method of a silicon-containing film.

6. In Paragraph 1, The flow rate of the above FNO gas is 300 sccm to 3000 sccm, Etching method of a silicon-containing film.

7. In Paragraph 1, The above etching gas further comprises an inert gas comprising one or more of argon (Ar), helium (He), krypton (Kr), and neon (Ne). Etching method of a silicon-containing film.

8. In Paragraph 7, The flow rate of the above inert gas is 500 sccm to 2500 sccm, Etching method of a silicon-containing film.

9. In Paragraph 8, A method for etching a silicon-containing film, wherein the value of Formula 1 below, which is the ratio to the flow rates of the reaction gas and the inert gas, is controlled within the range of 15 to 90%. <Equation 1> {(Reaction gas flow rate) / (Reaction gas flow rate + Inert gas flow rate)} × 100(%) 10. In Paragraph 1, The above predetermined pressure is controlled within the range of 400 mTorr to 5,000 mTorr, Etching method of a silicon-containing film.

11. In Paragraph 10, The above predetermined pressure is controlled within the range of 1,000 mTorr to 3,000 mTorr, Etching method of a silicon-containing film.

12. In Paragraph 1, The above predetermined power is controlled within the range of 1 kW to 10 kW, Etching method of a silicon-containing film.

13. A method for manufacturing a semiconductor device comprising a method for etching a silicon-containing film according to any one of claims 1 to 12.

14. A method for manufacturing a display device comprising a method for etching a silicon-containing film according to any one of claims 1 to 12.