Deposition method of silicon oxide film on semiconductor substrate and preparing method of semiconductor device comprising same

Abstract

The present invention relates to a deposition method of a silicon oxide film on a semiconductor substrate and, more specifically, to: a method for efficiently depositing a silicon oxide film on a semiconductor substrate with excellent selectivity by using an oxygen-containing fluorocarbon-based compound as an inhibitor; and to a preparing method of a semiconductor device, comprising same.

Description

Method for depositing a silicon oxide film on a semiconductor substrate and method for manufacturing a semiconductor device including the same

[0001] The present invention relates to a method for depositing a silicon oxide film on a semiconductor substrate, and more specifically, to a method for depositing a silicon oxide film on a semiconductor substrate efficiently and with excellent selectivity using an oxygen-containing fluorocarbon compound as an inhibitor, and a method for manufacturing a semiconductor device including the same.

[0002] Area-Selective Atomic Layer Deposition (AS-ALD) is a new bottom-up patterning method that can solve various technical problems such as alignment non-uniformity due to reduction in critical dimension (CD) and pattern surface roughness (LER / LWR) that can occur in the conventional top-down patterning process based on optical lithography in accordance with the trend of developing ultra-miniaturized semiconductor devices.

[0003] Patterning using area-selective atomic layer deposition (ALD) has primarily utilized self-assembled monolayer (SAM) inhibitors. However, SAM inhibitors themselves are solid materials with low vapor pressure, making them difficult to apply to vapor deposition.

[0004] In addition, the conventional technology manufactures a substrate by dissolving an inhibitor in an organic solvent such as toluene or tetrahydrofuran, heating to room temperature or below the boiling point of the inhibitor, and dipping the substrate in the solution for 24 to 48 hours. However, this method requires a very long process time, and due to the nature of the solution process, it is difficult to control surface adsorption, so the surface of the substrate on which the inhibitor is completely adsorbed is uneven, making it difficult to ensure uniformity, making it difficult to implement a semiconductor device that requires ultra-precision.

[0005] There is a need to develop a technology that can achieve ultra-precision patterning while improving the process efficiency of area-selective atomic layer deposition to solve the problems of such conventional technologies.

[0006] The present invention aims to provide a method for selectively depositing a silicon oxide film (SiO2) among metal / oxide structures with high precision by using an oxygen-containing fluorocarbon compound as an inhibitor, in order to overcome the problems and limitations existing in the prior art due to the use of inhibitors such as self-assembled monolayer (SAM) series.

[0007] In addition, the purpose is to improve the selectivity and process efficiency of thin film deposition by using the oxygen-containing fluorocarbon compound of the present invention as an inhibitor in the selective area deposition method (AS-ALD).

[0008] The purpose of the present invention is not limited to the aforementioned purposes, and other unmentioned purposes and advantages of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the purposes and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0009] In order to achieve the above object, according to one aspect of the present invention, a method for depositing a silicon oxide film on a semiconductor substrate can be provided, including: (a) preparing a substrate in which a growth region and a non-growth region coexist in a vacuum chamber; (b) a surface suppression step of treating the substrate with an oxygen-containing fluorocarbon compound as an suppressor and adsorbing it; (c) a step of removing the suppressor adsorbed on the growth region; and (d) a step of supplying a silicon precursor gas to deposit a silicon oxide film (SiO2) by selective atomic layer deposition (AS-ALD), wherein the growth region includes a silicon oxide film (SiO2), and the non-growth region includes at least one of a silicon nitride film (SiN), a titanium nitride film (TiN), a tungsten film (W), and copper (Cu).

[0010] The adsorption of the inhibitor in the growth region is a physical adsorption method, and the adsorption of the inhibitor in the non-growth region is a chemical adsorption method.

[0011] The above oxygen-containing fluorocarbon compound may be selected from a fluorinated ether represented by the following formula 1, a fluorinated ketone represented by the following formula 2, and a mixture thereof.

[0012] [Formula 1]

[0013] (In the above equation 1, R1 is C n F 2n+1 and R2 is C m F 2m+1 and R3 is C p F 2p+1 , R4 is a straight chain alkyl group having 1 to 5 carbon atoms, and n, m and p are each independently integers from 0 to 10.

[0014] [Formula 2]

[0015] (In the above formula 2, R5 is C(CF3) a (F) 3-a , and R6 is C(CF3) b (F) 3-b , and a and b are each independently integers from 0 to 3)

[0016] The above oxygen-containing fluorocarbon compounds are methyl nonafluorobutyl ether (C4F9OCH3), ethyl perfluorobutyl ether (C4F9OC2H5), 3-methoxyperfluoro(2-methylpentane), C6F 13 OCH3), 3-ethoxyperfluoro(2-methylhexane), C7F 15 It may include at least one of OC2H5) and perfluoro(2-methyl-3-pentanone (C2F5C(=O)C3F7).

[0017] The above step (c) is performed by a purge process of supplying purge gas to a vacuum chamber, and the purge gas may include at least one inert gas among nitrogen gas, helium gas, and argon gas.

[0018] The above steps (b) and (c) may be repeated one or more times.

[0019] The above silicon precursor gas may be an aminosilane series compound.

[0020] The above aminosilane compound may include at least one of hexachlorodisilane (HCDS), trimethylsilanedimethylamine (TMSDMA), tetrakisdimethylaminosilane (4DMAS), diisopropylaminosilane (DIPAS), trisdimethylaminosilane (3DMAS), and 1,2-bisdiisopropylaminodisilane (BDIPADS).

[0021] Prior to the above step (b), a step of cleaning the substrate with a solution containing hydrogen fluoride (HF) may be further included.

[0022] The temperature within the above vacuum chamber can be 100 to 200°C.

[0023] According to another aspect of the present invention, a method for manufacturing a semiconductor device can be provided, including a method for depositing a silicon oxide film on a semiconductor substrate according to an aspect of the present invention.

[0024] The semiconductor device may include one of DRAM, SRAM, and NAND Flash.

[0025] The method for depositing a silicon oxide film on a semiconductor substrate according to the present invention uses an oxygen-containing fluorocarbon compound as an inhibitor, which has a smaller molecular size than the SAM of the prior art, has high volatility, and exists as a liquid at room temperature, and can therefore be directly applied to AS-ALD.

[0026] According to the present invention, a method for depositing a silicon oxide film on a semiconductor substrate can selectively physically adsorb and desorb an oxygen-containing fluorocarbon compound as an inhibitor on a silicon oxide film (SiO2) substrate in a substrate structure in which a silicon oxide film (SiO2) (growth region) and a metal (non-growth region) coexist, and at the same time, by utilizing the characteristic that adsorption continues on a metal substrate, continuous application is possible to a subsequent oxide film process, and since SiO2 is selectively adsorbed only on the silicon oxide film (growth region), the selectivity of thin film deposition can be improved. At this time, as a physical adsorption method, a method of applying an inhibitor solution itself and performing solution treatment, a method of applying pressure to a volatile inhibitor solution to supply the inhibitor component to a chamber, a method of supplying the inhibitor component to a reactor for performing an ALD process and physically depositing it, etc. are possible, and the inhibitor application method is not particularly limited.

[0027] The oxygen-containing fluorocarbon compound used as an inhibitor in the method for depositing a silicon oxide film on a semiconductor substrate according to the present invention is a non-flammable fluid substance with a low global warming potential (GWP), and thus has the advantage of being environmentally friendly as it does not contribute to the formation of photochemical smog.

[0028] The method for depositing a silicon oxide film on a semiconductor substrate according to the present invention can be applied to a method for manufacturing a semiconductor device including a silicon oxide film, and has the advantage that it can also be usefully used in a method for manufacturing a semiconductor device requiring high precision and selectivity, such as DRAM, SRAM, NAND Flash, etc.

[0029] In addition to the effects described above, the effects of the present invention are described together with the description of matters for carrying out the invention below.

[0030] FIG. 1 is a schematic diagram of a process for depositing a silicon oxide film on a semiconductor substrate according to one embodiment of the present invention.

[0031] FIG. 2a is a graph showing the results of measuring the water contact angle (°) for each of the cases in which a SiO2 substrate is not treated in any way (indicated as “bare”), is cleaned with a hydrogen fluoride (HF) solution (indicated as “HF”), is treated with a solution of an oxygen-containing fluorocarbon compound as an inhibitor at room temperature (indicated as “RT treatment”), and is treated at 80°C (indicated as “80°C treatment”), according to one embodiment of the present invention.

[0032] FIG. 2b is a graph showing the results of measuring the water contact angle (°) for each of the cases in which the SiN substrate was not treated in any way (indicated as “bare”), was cleaned with a hydrogen fluoride (HF) solution (indicated as “HF”), was treated with a solution of an oxygen-containing fluorocarbon compound as an inhibitor at room temperature (indicated as “RT treatment”), and was treated at 80°C (indicated as “80°C treatment”), according to one embodiment of the present invention.

[0033] FIG. 2c is a graph showing the results of measuring the water contact angle (°) for each of the cases in which the TiN substrate was not treated in any way (indicated as “bare”), was cleaned with a hydrogen fluoride (HF) solution (indicated as “HF”), was treated with a solution of an oxygen-containing fluorocarbon compound as an inhibitor at room temperature (indicated as “RT treatment”), and was treated at 80°C (indicated as “80°C treatment”), according to one embodiment of the present invention.

[0034] FIG. 2d is a graph showing the results of measuring the water contact angle (°) for each of the cases in which the W substrate was not treated in any way (indicated as “bare”), was cleaned with a hydrogen fluoride (HF) solution (indicated as “HF”), was treated with a solution of an oxygen-containing fluorocarbon compound as an inhibitor at room temperature (indicated as “RT treatment”), and was treated at 80°C (indicated as “80°C treatment”), according to one embodiment of the present invention.

[0035] FIG. 3 is a graph showing the results of measuring the thickness of a thin film before and after each treatment, in which an ALD process of a SiO2 thin film was performed using HCDS (Hexachlorodisilane) as a silicon precursor gas after cleaning each of a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate with a hydrogen fluoride (HF) solution according to one embodiment of the present invention (indicated as “Ref.”) and in which the same ALD process was performed after solution treatment with an oxygen-containing fluorocarbon compound as an inhibitor (indicated as “inhibitor treatment”).

[0036] FIG. 4a shows TEM photographs of the thickness of a SiO2 thin film observed in a case where an ALD process of a SiO2 thin film was performed using HCDS (Hexachlorodisilane) as a silicon precursor gas after a TiN substrate was cleaned with a hydrogen fluoride (HF) solution according to one embodiment of the present invention (indicated as “Ref. TiN”) and in a case where the same ALD process was performed after a solution treatment of an oxygen-containing fluorocarbon compound as an inhibitor (indicated as “Inhibitor Treatment-TiN”).

[0037] FIG. 4b shows TEM photographs of the thickness of a SiO2 thin film observed when, according to one embodiment of the present invention, a W substrate was cleaned with a hydrogen fluoride (HF) solution and then an ALD process of a SiO2 thin film was performed using HCDS (Hexachlorodisilane) as a silicon precursor gas (indicated as “Ref. W”), and when the same ALD process was performed after a solution treatment of an oxygen-containing fluorocarbon compound as an inhibitor (indicated as “Inhibitor Treatment-W”).

[0038] FIG. 5 shows the results of measuring the water contact angle (°) and plotting the results for each substrate while increasing the exposure time of the inhibitor to 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, and 60 seconds, while cleaning a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate with a hydrogen fluoride (HF) solution and treating the solution with an oxygen-containing fluorocarbon compound as an inhibitor according to one embodiment of the present invention.

[0039] FIG. 6 is a graph showing the results of measuring the thickness of a thin film before and after each treatment when an ALD process of a SiO2 thin film was performed using HCDS (Hexachlorodisilane) as a silicon precursor gas after cleaning each of a SiO2 substrate, a SiN substrate, a TiN substrate, a W substrate, and a Cu substrate with a hydrogen fluoride (HF) solution according to one embodiment of the present invention (indicated as “Ref.”) and when the same ALD process was performed after depositing an oxygen-containing fluorocarbon compound as an inhibitor (indicated as “inhibitor treatment”).

[0040] Figures 7a to 7c illustrate TEM photographs of the thickness of SiO2 thin films observed in the experiment of Figure 6 on TiN substrates, W substrates, and Cu substrates when an ALD process was performed without inhibitor treatment (“Ref-substrate type”) and when the same ALD process was performed after applying an oxygen-containing fluorocarbon compound as an inhibitor by deposition treatment (“inhibitor treatment-substrate type”).

[0041] The aforementioned purposes, features, and advantages are described in detail below with reference to the present specification, thereby enabling those skilled in the art to readily implement the technical concepts of the present invention. In describing the present invention, detailed descriptions of known technologies related to the present invention will be omitted if they are deemed to unnecessarily obscure the gist of the invention.

[0042] In describing this specification, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of this specification, the detailed description is omitted.

[0043] In this specification, when a component is described as “including,” “having,” “consisting of,” “arranged,” or “equipped,” other parts may be added, unless “only” is used. When a component is described as singular, the plural is also included unless otherwise explicitly stated.

[0044] When it is said in this specification that an element is “located on” another element, this includes not only cases where the element is in contact with the other element, but also cases where another element exists between the elements.

[0045] Room temperature (RT) in this specification is interpreted to mean a temperature in the range of 15 to 25°C.

[0046] In this specification, the thickness of the thin film was measured using an ellipsometer, and the surface was observed using a high-resolution transmission electron microscope (TEM).

[0047] In interpreting the components in this specification, even if there is no separate explicit description, it is interpreted to include the range of error.

[0048]

[0049] Hereinafter, the present invention will be described in more detail.

[0050] FIG. 1 is a schematic diagram of a process for depositing a silicon oxide film on a semiconductor substrate according to an embodiment of the present invention. FIG. 1a shows (a) a step of preparing a substrate in which a growth region and a non-growth region coexist in a vacuum chamber, where GA represents a growth region and NGA represents a non-growth region. Such a growth region (GA) and a non-growth region (NGA) schematically represent a structure in a manufacturing process of a semiconductor device such as a DRAM. The substrate may be a semiconductor wafer, which is a deposition target structure, and may be, for example, a silicon wafer, but is not necessarily limited thereto. In addition, the growth region and the non-growth region do not necessarily have to be in contact with the substrate, and a thin film formed of a different material may be interposed therebetween, and may be, for example, various thin films such as an insulating film or a conductive film.

[0051] The growth region may include a silicon oxide film (SiO2), and the non-growth region may include one or more of a silicon nitride film (SiN), a titanium nitride film (TiN), a tungsten film (W), and a copper film (Cu). As described below, when an oxygen-containing fluorocarbon compound is used as an inhibitor of the present invention, it has been experimentally confirmed that a better selectivity is exhibited in the ALD process when the non-growth region is a titanium nitride film (TiN) or a tungsten film (W).

[0052] Figure 1b is a surface inhibition step in which an oxygen-containing fluorocarbon compound as an inhibitor is adsorbed by solution treatment on the substrate (b). When the inhibitor is supplied into a vacuum chamber, it is physically adsorbed on the silicon oxide film of GA and chemically adsorbed on NGA.

[0053] According to one embodiment of the present invention, the oxygen-containing fluorocarbon compound as the inhibitor may be selected from among fluorinated ethers, fluorinated ketones, and mixtures thereof, but is not necessarily limited thereto.

[0054] In the present invention, fluorinated ether means an ether compound in which part or all of the compound is fluorinated, and may be represented by the following formula 1.

[0055] [Formula 1]

[0056] In the above formula 1, R1 is C n F 2n+1 and R2 is C m F 2m+1 and R3 is C p F 2p+1 , and R4 is a straight-chain alkyl group having 1 to 5 carbon atoms, and n, m and p can each independently be an integer from 0 to 10. For example, in the above formula 1, n, m and p can each independently be an integer from 1 to 8, 2 to 7, or 3 to 6, and n, m and p can be the same as or different from each other.

[0057] In the present invention, a fluorinated ketone means a ketone compound in which part or all of the ketone compound is fluorinated, and may be represented by the following formula 2.

[0058] [Formula 2]

[0059] In the above formula 2, R5 is C(CF3) a (F) 3-a , and R6 is C(CF3) b (F) 3-b , a and b can each independently be integers from 0 to 3, and a and b can be the same or different from each other.

[0060] According to one embodiment of the present invention, the oxygen-containing fluorocarbon compound is methyl nonafluorobutyl ether (C4F9OCH3), ethyl perfluorobutyl ether (C4F9OC2H5), 3-methoxyperfluoro(2-methylpentane), C6F 13 OCH3), 3-ethoxyperfluoro(2-methylhexane), C7F 15 It may include at least one of OC2H5) and perfluoro(2-methyl-3-pentanone (C2F5C(=O)C3F7), but is not limited thereto.

[0061] The oxygen-containing fluorocarbon compound of the present invention, when in a liquid state at room temperature, can directly process the oxygen-containing fluorocarbon compound in a liquid state, thereby improving processability, and since the drying time at room temperature is short, it can be easily applied when treating the inhibitor in an ALD deposition process. In addition, the oxygen-containing fluorocarbon compound inhibitor of the present invention has excellent adsorption properties with an ultra-thin film thickness (sub-micron unit), exhibits excellent water- and oil-repellent performance, can form a transparent and highly flexible film, and exhibits excellent water- and oil-repellent performance.

[0062] FIG. 1c is a step for removing the inhibitor adsorbed on the growth region, which can be performed by a purge process that supplies a purge gas to a vacuum chamber, and the purge gas includes at least one inert gas selected from the group consisting of nitrogen gas, helium gas, and argon gas. As shown in FIGS. 1c to 1e, an ALD process using the Discrete Feeding Method (DMF) is performed in which a series of processes including adsorbing the inhibitor, removing the inhibitor from the GA through a purge process, adsorbing the inhibitor again, and then performing the purge process again are repeated. This series of processes can be performed approximately 2 to 5 times to uniformly and effectively adsorb the inhibitor. In this way, since the amine-based fluorocarbon inhibitor of the present invention is physically adsorbed on a silicon oxide film, it can be easily desorbed by a purge process, whereas since it is chemically adsorbed on a titanium nitride (TiN) film or the like, the inhibitor can be efficiently adsorbed on a non-growth region, and therefore, there is an advantage in that the process for removing the inhibitor is simplified.

[0063] According to one embodiment of the present invention, before loading the substrate into a vacuum chamber or (b) before the step of adsorbing the inhibitor, a step of pretreating the substrate may be further included. The pretreating step is to remove impurities and natural oxide films existing on the substrate surface. The pretreating step may be a step of cleaning with a cleaning solution such as a solution containing hydrogen fluoride (HF), and for example, cleaning may be performed for about 30 seconds to 1 minute with a 0.5 wt% HF solution. After the cleaning step, a rinsing process, a drying process, etc. may be further performed. Purified water may be used in the rinsing process, and nitrogen gas or the like may be used in the drying process, but the present invention is not necessarily limited thereto.

[0064] Then, as shown in Fig. 1f, (d) the ALD process is implemented through the step of supplying a silicon precursor gas and depositing a silicon oxide film (SiO2) using selective atomic layer deposition (AS-ALD). That is, the silicon precursor is supplied into the vacuum chamber so that it can be adsorbed on the silicon oxide film in the growth region. At this time, the silicon precursor is not adsorbed at all on the non-growth region, or if it is adsorbed, a relatively small amount is adsorbed. Depending on the embodiment, the silicon precursor may not be adsorbed on the non-growth region during the first half of the atomic layer deposition process cycle, but after a predetermined number of cycles, the silicon precursor may be adsorbed on the non-growth region as well. According to the present invention, such selective adsorption of the silicon precursor utilizes the inherent selective properties of the material, and utilizes the property that the silicon precursor is adsorbed only on the silicon oxide film in the growth region or is adsorbed on the silicon oxide film in a relatively larger amount than on the non-growth region under the same process conditions (e.g., conditions such as temperature, pressure, and supply amount of the silicon precursor gas inside the process chamber). Therefore, the silicon precursor may be supplied to a vacuum chamber set at a relatively low temperature, for example, approximately 50 to 300°C, or approximately 100 to 200°C. The process temperature may vary depending on the type of precursor used in the subsequent thin film deposition process.

[0065] According to one embodiment of the present invention, an aminosilane-based compound may be used as a silicon precursor. The aminosilane-based compound has a property of being easily adsorbed on the surface of a silicon oxide film having an -OH functional group rather than on the surface of a titanium nitride film or a tungsten film without an -OH functional group at the terminal. For example, the aminosilane-based compound may include, but is not necessarily limited to, one or more of hexachlorodisilane (HCDS), trimethylsilanedimethylamine (TMSDMA), tetrakisdimethylaminosilane (4DMAS), diisopropylaminosilane (DIPAS), trisdimethylaminosilane (3DMAS), and 1,2-bisdiisopropylaminodisilane (BDIPADS).

[0066] An oxidizing agent may be supplied to the vacuum chamber together or continuously to react with the aminosilane compound, for example, by plasma. The oxidizing agent may include, but is not limited to, one or more of ozone gas, oxygen gas, and a mixed gas of oxygen and hydrogen.

[0067] The vacuum chamber into which the silicon precursor is supplied can be set to a pressure of about 2 Torr or less inside. And as mentioned above, the internal temperature of the vacuum chamber can be set to, for example, about 50 to 300°C, for example, about 100 to 200°C. The silicon precursor may be supplied into the vacuum chamber alone in a gaseous state, for example, by evaporation or sublimation, or may be supplied into the vacuum chamber together with a predetermined carrier gas, for example, nitrogen (N2) gas, argon (Ar) gas, helium (He) gas, and / or hydrogen (H2) gas. Alternatively, the silicon precursor may be evaporated or sublimated inside the vacuum chamber to become a gaseous state. Although not shown in the flowchart of Fig. 1, after introducing the silicon precursor into the vacuum chamber, a purge process may be additionally performed to supply a purge gas into the vacuum chamber to remove the remaining silicon precursor and carrier gas that are not adsorbed on the substrate from the vacuum chamber. An inert gas, such as nitrogen gas or argon gas, may be used as the purge gas.

[0068] Although not shown in the flowchart of Fig. 1, a purge gas is supplied into the vacuum chamber to exhaust the remaining gases, reaction byproducts, etc. to the outside of the vacuum chamber. Accordingly, one cycle of the atomic layer deposition (ALD) process for selectively depositing a silicon oxide film is completed. Thereafter, the ALD process cycle is repeated a predetermined number of times until a silicon oxide film of the desired thickness is formed on the silicon oxide film in the growth region. At this time, as the number of repetitions of the cycle increases, an additional silicon oxide film is formed on the silicon oxide film in the growth region, whereas no silicon oxide film is formed at all on the non-growth region, or the silicon oxide film may be formed with a significantly smaller thickness than that formed on the silicon oxide film. If a silicon oxide film of a small thickness is formed in the non-growth region, it can be removed through a post-processing process such as atomic layer etching, so that a silicon oxide film of the desired thickness is ultimately formed only in the growth region.

[0069] Fig. 2a is a graph showing the results of measuring the water contact angle (WCA, °) for the cases where a SiO2 substrate was prepared without any treatment (indicated as “bare”), washed with hydrogen fluoride (HF) solution (indicated as “HF”), treated with a solution of 3-methoxyperfluoro(2-methylpentane), an oxygen-containing fluorocarbon compound (indicated as “RT treatment”), and treated at 80°C (indicated as “80°C treatment”), respectively. Fig. 2b is the same experiment as Fig. 2a except that a SiN substrate was used instead of the SiO2 substrate, Fig. 2c is the same experiment as Fig. 2a except that a TiN substrate was used instead of the SiO2 substrate, and Fig. 2d is the same experiment as Fig. 2a except that a W substrate was used instead of the SiO2 substrate. In this case, the room temperature and 80°C treatments were performed by applying the solution for 24 hours.

[0070] As can be seen in Fig. 2b, the water contact angle of the SiN substrate increased from 36° to 67° after HF cleaning treatment and solution treatment with 3-methoxyperfluoro(2-methylpentane) as an inhibitor at 80°C. As can be seen in Fig. 2c, the water contact angle of the TiN substrate also increased from 42° to 93° after HF cleaning treatment and solution treatment with 3-methoxyperfluoro(2-methylpentane) as an inhibitor at 80°C. In Fig. 2d, the water contact angle of the W substrate also increased from 37° to 87° after HF cleaning treatment and solution treatment with 3-methoxyperfluoro(2-methylpentane) at 80°C. Thus, it was confirmed that 3-methoxyperfluoro(2-methylpentane) as an inhibitor was adsorbed on the SiN substrate, TiN substrate, and W substrate, respectively, to exhibit water repellency.

[0071] On the other hand, as can be seen in Fig. 2a, even when the SiO2 substrate was treated with a solution of 3-methoxyperfluoro(2-methylpentane) as an inhibitor at 80°C after HF cleaning, the water contact angle was only 56.6°. Even if some of the inhibitor was adsorbed, the adsorption characteristics were much lower than those of the non-growth metal substrate (SiN substrate, TiN substrate, W substrate), confirming that it is suitable for the AS-ALD process and can exhibit high selectivity when depositing a SiO2 thin film. In addition, from the water contact angle measurement results, it was shown that the selectivity implementation on TiN would be the best among various metal substrates.

[0072] The experiment was conducted in the same manner as in Figs. 2a to 2d, but instead of the oxygen-containing fluorocarbon compound 3-methoxyperfluoro(2-methylpentane) solution (indicated as “inhibitor 1”), a methyl nanofluorobutyl ether solution (indicated as “inhibitor 2”), an ethyl perfluoro ether solution (indicated as “inhibitor 3”), a 3-ethoxyperfluoro(2-methylhexane) solution (indicated as “inhibitor 4”), and a perfluoro(2-methyl-3-pentanone) solution (indicated as “inhibitor 5”) were used, respectively. The change in water contact angle after solution treatment at 80°C after HF cleaning treatment is shown in Table 1 below.

[0073] [Table 1]

[0074]

[0075] From the above Table 1, it can be seen that when using various types of fluorinated ether or fluorinated ketone substances as the inhibitors of the present invention, the water contact angle on the SiO2 substrate increased, but only to the level of 30 to 50°, whereas the water contact angle on the SiN substrate, TiN substrate, and W substrate increased further, and it was confirmed that excellent water repellency could be achieved, especially on the TiN substrate.

[0076] The GWP of the above inhibitor 1 was 210, the GWP of inhibitor 2 was 297, the GWP of inhibitor 3 was 59, the GWP of inhibitor 4 was 90, and the GWP of inhibitor 5 was less than 1, all of which had low GWPs (global warming potentials, measured according to the Intergovernmental Panel on Climate Change (IPCC) 2013 method) and were thus environmentally friendly substances.

[0077] Figure 3 is a graph showing the results of measuring the thickness (nm) of the thin film using an ellipsometer before and after each treatment, in the case where an ALD process of a SiO2 thin film was performed using HCDS (Hexachlorodisilane) as an aminosilane compound after cleaning a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate with a hydrogen fluoride (HF) solution (indicated as “Ref.”) and in the case where an ALD process of a SiO2 thin film was performed in the same manner as above after solution treatment with a 3-methoxyperfluoro(2-methylpentane) solution as an oxygen-containing fluorocarbon compound as an inhibitor (indicated as “inhibitor treatment”). The inhibitor solution treatment was performed by applying the solution at 80°C for 24 hours, followed by baking at 250°C for 10 minutes. The above ALD process 1 cycle was performed under a temperature condition of 100℃ as follows: <Si deposition process using HCDS (Hexachlorodisilane) (6 seconds) - purge process (30 seconds) - oxidation process using H2O (8 seconds) - purge process (60 seconds)>.

[0078] Additionally, TEM analysis images of the TiN substrate and the W substrate in the case of “Ref” and “inhibitor treatment” are shown in Figs. 4a and 4b, respectively.

[0079] As can be seen in FIGS. 3, 4a, and 4b, in the case of the SiO2 substrate, the thickness growth of the SiO2 thin film changed from 4.3 nm to 3.9 nm before and after the inhibitor treatment, confirming that although the inhibitor was adsorbed on the SiO2 substrate, which was a part of the growth area, the growth of the SiO2 thin film was not reduced. In the case of the SiN substrate, when the inhibitor was not treated, the SiO2 thin film grew to 4.7 nm, whereas after the inhibitor treatment, it grew to 2.5 nm, confirming that the inhibition performance could be expressed. In the case of the TiN substrate, when the inhibitor was not treated, the growth of the SiO2 thin film was suppressed from 3.5 nm to 1.6 nm, and in the case of the W substrate, the growth of the SiO2 thin film was also suppressed from 3.4 nm to 2.4 nm when the inhibitor was not treated.

[0080] In terms of selectivity, the TiN substrate showed the best selectivity of 2.3 nm (3.9 nm - 1.6 nm = 2.3 nm) compared to the SiO2 thin film grown on the SiO2 substrate, and it was confirmed that the W substrate also showed an excellent selectivity of 1.5 nm (3.9 nm - 2.4 nm = 1.5 nm).

[0081] Fig. 5 shows that SiO2 substrates, SiN substrates, TiN substrates, and W substrates were cleaned with hydrogen fluoride (HF) solution and placed in a chamber temperature-controlled at 100°C. Then, a 3-methoxyperfluoro(2-methylpentane) solution, which is an inhibitor, was placed in a canister at room temperature and moved to the chamber at 100°C under a pressure of approximately 0.5 Torr. Since the 3-methoxyperfluoro(2-methylpentane) solution, which is an inhibitor solution, is highly volatile, it may volatilize when pressure is applied and the inhibitor may be deposited on the substrate when moved into the chamber. At this time, the water contact angle (°) was measured while increasing the treatment time (exposure time to the solution) for the inhibitor solution to 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, and 60 seconds, respectively.

[0082] As can be seen in Fig. 5, the water contact angle increased rapidly from the treatment time of 10 seconds, confirming that it is suitable for the ALD process. Since the water contact angle did not increase any further from 10 seconds to 60 seconds, it was determined that the inhibitor treatment time of approximately 10 seconds was the most appropriate.

[0083] Figure 6 is a graph showing the results of measuring the thickness (nm) of the thin film using an ellipsometer before and after each treatment, in the case where an ALD process of a SiO2 thin film was performed using HCDS (Hexachlorodisilane) as an aminosilane compound after cleaning with a hydrogen fluoride (HF) solution on a SiN substrate, a TiN substrate, a W substrate, and a Cu substrate, respectively (indicated as “Ref.”) and in the case where an ALD process of a SiO2 thin film was performed in the same manner as above after solution treatment with a 3-methoxyperfluoro(2-methylpentane) solution as an oxygen-containing fluorocarbon compound as an inhibitor (indicated as “inhibitor treatment”).

[0084] Specifically, the ALD process is performed under a temperature condition of 100°C, and one cycle consists of <inhibitor deposition (10 seconds) - first purge process (60 seconds) - Si deposition process using HCDS (Hexachlorodisilane) (6 seconds) - second purge process (30 seconds) - oxidation process using H2O (8 seconds) - third purge process (60 seconds)>, and the target thickness of the SiO2 thin film is 7.5 nm. In “Ref”, the application of the inhibitor solution and the first purge process are excluded.

[0085] In order to confirm the selectivity before and after inhibitor treatment on the TiN substrate, W substrate, and Cu substrate in the experiment of Fig. 6 above, TEM analysis was performed and the results are shown in Figs. 7a, 7b, and 7c, respectively.

[0086] As can be seen in FIGS. 6, 7a, 7b, and 7c, in the case of the SiO2 substrate, the thickness growth of the SiO2 thin film before and after the inhibitor treatment changed from 7.02 nm to 7.25 nm, showing the result of increasing the growth of the SiO2 thin film. The selectivity for the SiN substrate, TiN substrate, W substrate, and Cu substrate, which were the experimental targets in FIG. 6, compared to the SiO2 thin film grown on the SiO2 substrate was calculated and is shown in Table 2 below.

[0087] [Table 2]

[0088]

[0089] As can be seen from Table 2 above, when the inhibitor of the present invention was applied by a deposition method, it was confirmed that the deposition of SiO2 thin films was suppressed on all of the SiN substrates, TiN substrates, W substrates, and Cu substrates.

[0090]

[0091] Although the present invention has been described in more detail with reference to the embodiments and drawings of the present specification, the present specification is not necessarily limited to these embodiments and drawings, and various modifications may be implemented without departing from the technical spirit of the present specification. Therefore, the embodiments and drawings disclosed in the present specification are not intended to limit the technical spirit of the present specification, but to explain, and the scope of the technical spirit of the present specification is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of protection of the present specification should be interpreted by the claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of rights of the present specification.

Claims

1. (a) A step of preparing a substrate in which a growth region and a non-growth region coexist in a vacuum chamber; (b) a surface inhibition step of treating and adsorbing an oxygen containing fluorocarbon compound as an inhibitor on the substrate; (c) a step of removing the inhibitor adsorbed in the growth area; and (d) a step of supplying a silicon precursor gas to deposit a silicon oxide film (SiO2) by selective atomic layer deposition (AS-ALD); The above growth region includes a silicon oxide film (SiO2), The above non-growth region includes at least one of a silicon nitride film (SiN), a titanium nitride film (TiN), a tungsten film (W), and copper (Cu). A method for depositing a silicon oxide film on a semiconductor substrate.

2. In paragraph 1, The adsorption of the inhibitor to the above growth area is a physical adsorption method. The adsorption of the inhibitor in the above non-growth area is a chemisorption method. A method for depositing a silicon oxide film on a semiconductor substrate.

3. In paragraph 1, The above oxygen-containing fluorocarbon compound is selected from among a fluorinated ether represented by the following formula 1, a fluorinated ketone represented by the following formula 2, and a mixture thereof. Method for depositing silicon oxide film on semiconductor substrate: [Formula 1] In the above formula 1, R1 is C n F 2n+1 , and R2 is C m F 2m+1 , and R3 is C p F 2p+1 , R4 is a straight-chain alkyl group having 1 to 5 carbon atoms, n, m and p are each independently an integer from 0 to 10, [Formula 2] In the above formula 2, R5 is C(CF3) a (F) 3-a , and R6 is C(CF3) b (F) 3-b , and a and b are each independently integers from 0 to 3.

4. In paragraph 3, The above oxygen-containing fluorocarbon compounds are methyl nonafluorobutyl ether (C4F9OCH3), ethyl perfluorobutyl ether (C4F9OC2H5), 3-methoxyperfluoro(2-methylpentane), C6F 13 OCH3), 3-ethoxyperfluoro(2-methylhexane), C7F 15 A method for depositing a silicon oxide film on a semiconductor substrate, comprising at least one of OC2H5) and perfluoro(2-methyl-3-pentanone (C2F5C(=O)C3F7).

5. In paragraph 1, The above step (c) is performed by a purge process that supplies purge gas to a vacuum chamber, The above purge gas comprises at least one inert gas among nitrogen gas, helium gas and argon gas. A method for depositing a silicon oxide film on a semiconductor substrate.

6. In paragraph 1, The above steps (b) and (c) are repeated at least once. A method for depositing a silicon oxide film on a semiconductor substrate.

7. In paragraph 1, The above silicon precursor gas is an aminosilane series compound. A method for depositing a silicon oxide film on a semiconductor substrate.

8. In paragraph 7, The above aminosilane compound comprises at least one of hexachlorodisilane (HCDS), trimethylsilanedimethylamine (TMSDMA), tetrakisdimethylaminosilane (4DMAS), diisopropylaminosilane (DIPAS), trisdimethylaminosilane (3DMAS), and 1,2-bisdiisopropylaminodisilane (BDIPADS). A method for depositing a silicon oxide film on a semiconductor substrate.

9. In paragraph 1, Prior to the step (b), further comprising a step of cleaning the substrate with a solution containing hydrogen fluoride (HF). A method for depositing a silicon oxide film on a semiconductor substrate.

10. In paragraph 1, The temperature inside the above vacuum chamber is 100 to 200 ℃. A method for depositing a silicon oxide film on a semiconductor substrate.

11. A method for depositing a silicon oxide film on a semiconductor substrate according to any one of claims 1 to 10, A method for manufacturing a semiconductor device.

12. In paragraph 11, A method for manufacturing a semiconductor device, wherein the semiconductor device includes one of DRAM, SRAM, and NAND Flash.

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