Deposition method of silicon oxide film on semiconductor substrate, and preparation 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 depositing, with excellent selectivity, a silicon oxide film on a semiconductor substrate by using an amine-based fluorocarbon inhibitor; and a preparation method of 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 amine-based fluorocarbon 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 amine-based 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 present invention aims to improve the selectivity and process efficiency of thin film deposition by introducing the amine-based fluorocarbon inhibitor of the present invention into 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 and adsorbing an amine-based fluorocarbon inhibitor on the substrate; (c) a step of removing the inhibitor 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), and a tungsten film (W).

[0010] The adsorption of the inhibitor in the growth region is a physical adsorption method, the non-growth region is at least one of a titanium nitride film (TiN) and a tungsten film (W), and the adsorption of the inhibitor in the non-growth region is a chemical adsorption method.

[0011] The above amine-based fluorocarbon inhibitor may include one or more compounds represented by the following formula 1.

[0012] <Formula 1> N{(CF2) n (CF3)}3(n is an integer from 0 to 20)

[0013] The above amine-based fluorocarbon inhibitor may include at least one of perfluorotributylamine, perfluorotripentylamine, and perfluorotripropylamine.

[0014] 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.

[0015] The above steps (b) and (c) may be repeated one or more times.

[0016] The above silicon precursor gas may be an aminosilane series compound.

[0017] The above aminosilane compound may include at least one of trimethylsilyldimethylamine (TMSDMA), tetrakisdimethylaminosilane (4DMAS), diisopropylaminosilane (DIPAS), trisdimethylaminosilane (3DMAS), and 1,2-bisdiisopropylaminodisilane (BDIPADS).

[0018] Prior to the above step (b), a step of cleaning the substrate with a solution containing hydrogen fluoride (HF) may be further included.

[0019] The temperature within the above vacuum chamber can be 100 to 200°C.

[0020] 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 one aspect of the present invention.

[0021] The semiconductor device may include one of DRAM, SRAM, and NAND Flash.

[0022] The method for depositing a silicon oxide film on a semiconductor substrate according to the present invention uses an amine-based 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.

[0023] The method for depositing a silicon oxide film on a semiconductor substrate according to the present invention can selectively physically adsorb and desorb an amine-based fluorocarbon inhibitor material onto a silicon oxide film 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, can continuously apply the method to a subsequent oxide film process by utilizing the characteristic that adsorption continues on a metal substrate, and can improve the selectivity of thin film deposition because SiO2 is selectively adsorbed only on the silicon oxide film (growth region).

[0024] 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.

[0025] 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.

[0026] 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.

[0027] FIG. 2 is a graph showing the results of measuring the water contact angle (°) for each of a SiO2 substrate, a SiN substrate, a TiN substrate, and a W thin film after cleaning with a hydrogen fluoride (HF) solution (indicated as “after HF-Cleaning”) and after treating with an amine-based fluorocarbon inhibitor (indicated as “after PFTPA”) according to one embodiment of the present invention.

[0028] FIG. 3a is a graph showing the results of measuring the water contact angle (°) for each of a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate after being treated with an amine-based fluorocarbon inhibitor following a cleaning treatment with a hydrogen fluoride (HF) solution (denoted as “after PFTPA”) and after being heat-treated at a temperature of 250° C. for 10 minutes in a chamber (denoted as “after Thermal”) according to one embodiment of the present invention.

[0029] FIG. 3b is a graph showing the results of measuring the water contact angle (°) for each of a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate after being treated with an amine-based fluorocarbon inhibitor following a cleaning treatment with a solution containing hydrogen fluoride (HF) (denoted as “after PFTPA”) and after being heat-treated at a temperature of 150° C. for 10 minutes in a chamber (denoted as “after Thermal”) according to one embodiment of the present invention.

[0030] FIG. 4a is a graph showing the results of measuring the thickness of a thin film before and after each treatment when, according to one embodiment of the present invention, an ALD process of a SiO2 thin film with a thickness of 50 Å was performed at 150°C using BDIPADS as an aminosilane compound after cleaning a SiO2 substrate and a SiN substrate with a hydrogen fluoride (HF) solution (indicated as “Ref.”) and when, after cleaning with a hydrogen fluoride (HF) solution, the same atomic layer deposition process was performed after treating with an amine-based fluorocarbon inhibitor (indicated as “PFTPA”).

[0031] FIG. 4b shows TEM photographs of the thickness of thin films before and after each treatment, in which a SiO2 thin film was subjected to an ALD process at 150°C with a thickness of 50 Å using BDIPADS as an aminosilane compound after being cleaned with a hydrogen fluoride (HF) solution on a TiN substrate and a W substrate according to one embodiment of the present invention (indicated as “Ref.”), and in which the same atomic layer deposition process was performed after being cleaned with a hydrogen fluoride (HF) solution and treated with an amine-based fluorocarbon inhibitor (indicated as “PFTPA”).

[0032] FIG. 5 is a graph showing the results of selective vapor deposition of a silicon oxide film using BDIPADS as an aminosilane compound in an ALD process after cleaning a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate with a hydrogen fluoride (HF) solution and treating them with an amine-based fluorocarbon inhibitor according to one embodiment of the present invention, with the exposure time of the inhibitor adjusted to 10 seconds, 30 seconds, and 60 seconds, respectively. In this case, FIGS. 5a, 5b, and 5c differ in that the ALD vapor deposition conditions are set to room temperature (RT), 60°C, and 80°C, respectively.

[0033] FIG. 6 is a graph and TEM image showing the results of measuring the thickness change of a thin film after cleaning with a hydrogen fluoride (HF) solution on a SiO2 substrate, a TiN substrate, and a W substrate and performing 100 ALD processes (selective vapor deposition of a silicon oxide film using BDIPADS as an aminosilane compound) according to one embodiment of the present invention (indicated as “Ref”), and after treating with an amine-based fluorocarbon inhibitor after cleaning and performing 100 ALD processes in the same manner as above (indicated as “PFTPA”). At this time, FIG. 6a, FIG. 6b, and FIG. 6c differ in that the target thicknesses of the silicon oxide film are set to 5 nm, 7.5 nm, and 10 nm, respectively.

[0034] FIG. 7 is a graph (FIG. 7a) and a TEM photograph (FIG. 7b) showing the results of measuring the change in the thickness of a thin film after cleaning a substrate in which a SiO2 substrate and a TiN substrate coexist with a hydrogen fluoride (HF) solution according to one embodiment of the present invention, and performing 100 ALD processes (selective vapor deposition of a silicon oxide film using BDIPADS as an aminosilane compound) with a target thickness of 5 nm (denoted as “Ref 100cy”), and after treating with an amine-based fluorocarbon inhibitor after cleaning and performing 100 ALD processes in the same manner as above (denoted as “PFTPA 100cy”).

[0035] 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.

[0036] 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.

[0037] 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.

[0038] When it is said in this specification that an element is “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.

[0039] Room temperature (RT) in this specification is interpreted to mean a temperature in the range of 15 to 25°C.

[0040] In interpreting the components in this specification, even if there is no separate explicit description, it is interpreted to include the range of error.

[0041]

[0042] Hereinafter, the present invention will be described in more detail.

[0043] 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.

[0044] 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), and a tungsten film (W). As described below, it has been experimentally confirmed that the amine-based fluorocarbon compound, which is an inhibitor of the present invention, exhibits a better selectivity in an ALD process when the non-growth region includes a titanium nitride film (TiN) or a tungsten film (W).

[0045] Figure 1b is (b) a surface inhibition step of adsorbing an amine-based fluorocarbon inhibitor on the substrate, wherein when the inhibitor is supplied into a vacuum chamber, it is physically adsorbed on a silicon oxide film, which is GA, and chemically adsorbed on NGA. An amine-based fluorocarbon inhibitor according to one embodiment of the present invention may include one or more compounds represented by the following formula 1, but is not necessarily limited thereto.

[0046] <Formula 1> N{(CF2) n (CF3)}3(n is an integer from 0 to 20)

[0047] For example, n in the above equation 1 can be 0 to 10, 1 to 8, or 3 to 6.

[0048] According to one embodiment of the present invention, the amine-based fluorocarbon inhibitor may include one or a mixture of two or more selected from perfluorotributylamine, perfluorotripentylamine, and perfluorotripropylamine, but is not necessarily limited thereto.

[0049] According to one embodiment of the present invention, when the boiling point of the amine-based fluorocarbon inhibitor at normal pressure exceeds 100°C and exists in a liquid state at room temperature, the amine-based fluorocarbon inhibitor can be directly processed, thereby improving process convenience, and since perfluorocarbon series materials are volatile, they can be easily applied when processing inhibitors in an ALD deposition process.

[0050] 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.

[0051] 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.

[0052] 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 to a relatively low temperature, for example, about 50 to 300°C, for example, about 100 to 200°C. At this time, the process temperature may vary depending on the type of precursor used in the subsequent thin film deposition process. According to one embodiment of the present invention, an aminosilane-based compound may be used as the silicon precursor. The aminosilane-based compound has a characteristic 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 trimethylsilyldimethylamine (TMSDMA), tetrakisdimethylaminosilane (4DMAS), diisopropylaminosilane (DIPAS), trisdimethylaminosilane (3DMAS), and 1,2-bisdiisopropylaminodisilane (BDIPADS).

[0053] An oxidizing agent may be supplied to the vacuum chamber together or continuously to react with the aminosilane gas, and may be supplied, for example, in a plasma manner. The oxidizing agent may include, but is not necessarily limited to, one or more of ozone gas, oxygen gas, and a mixed gas of oxygen and hydrogen.

[0054] 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 to 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.

[0055] 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.

[0056] Fig. 2 is a graph showing the results of measuring the water contact angle (WCA (°)) for each of a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate after cleaning them with a hydrogen fluoride (HF) solution (indicated as “after HF-Cleaning”) and after applying perfluorotributylamine (PFTPA) at 100°C for 24 hours to inhibit the surface (indicated as “after PFTPA”). Since perfluorotributylamine (PFTPA) has a boiling point of approximately 130°C at normal pressure, it exists in a liquid state at room temperature. Therefore, treating with PFTPA means treating PFTPA as a solution in the liquid state itself. This is to determine the hydrophilicity or water-repellent properties of the surface of the target for measuring the water contact angle, and it is judged that the higher the water contact angle value, the more increased the water-repellent property. As can be seen from the WCA measurement results in Fig. 2, the WCA of the TiN substrate and the W substrate was approximately 30° after HF cleaning, but increased to over 90° after applying the inhibitor, confirming that the coating of PFTPA was completed and the substrate became water-repellent.

[0057] FIG. 3a is a graph showing the results of measuring the water contact angle (WCA, °) for a SiO2 substrate, a SiN substrate, a TiN substrate, and a W substrate after cleaning with a hydrogen fluoride (HF) solution and treating with an amine-based fluorocarbon inhibitor (denoted as “after PFTPA”) and after heat treatment at 250°C for 10 minutes in a chamber (denoted as “after Thermal”) according to one embodiment of the present invention. FIG. 3b is the same as FIG. 3a, except that the heat treatment temperature in the chamber is set to 150°C instead of 250°C. The experiments of FIGS. 3a and 3b are intended to confirm the thermal stability for selecting process conditions for subsequent SiO2 thin film deposition after applying the inhibitor. As can be seen in Fig. 3a, under the heat treatment process condition of 250°C, the WCA of the TiN substrate decreased from 96.1° to 71.7° after the heat treatment, and the WCA of the W substrate decreased significantly from 91.8° to 28.5° after the heat treatment.

[0058] On the other hand, as can be seen in Fig. 3b, under the heat treatment process conditions of 150°, the WCA of the TiN substrate decreased from 96.1° to 90.1° after the heat treatment, and the WCA of the W substrate decreased from 91.8° to 80.2° after the heat treatment, indicating that the WCA decrease was significantly reduced and the thermal stability was improved. This can be interpreted as the 150°C process being easier for subsequent processes than the 250°C process. Meanwhile, it was confirmed that the WCA of the three types of substrates (SiN, TiN, and W) decreased in the heat treatment at 150°C and 250°C, while that of the SiO2 substrate increased slightly (approximately 3-4°).

[0059] Fig. 4a is a graph showing the results of measuring the thickness of the thin film before and after each treatment when an ALD process of a 50Å thick SiO2 thin film was performed at 150°C using BDIPADS as an aminosilane compound after cleaning with a hydrogen fluoride (HF) solution on a SiO2 substrate and a SiN substrate (indicated as “Ref.”) and when the same atomic layer deposition process was performed after cleaning with a hydrogen fluoride (HF) solution and treating with an amine-based fluorocarbon inhibitor (indicated as “PFTPA”). Fig. 4b is a graph showing the results of the experiment in the same manner as Fig. 4a, except that the substrates were changed to a TiN substrate and a W substrate, and the thickness of the thin film before and after the treatment was observed.

[0060] As can be seen in Fig. 4a, the SiN substrate was a metal substrate with a rather weak water-repellent effect (see the WCA measurement results in Fig. 2), but after depositing a subsequent SiO2 thin film with a 5.0 nm target, it showed a difference of only about 0.3 nm compared to SiO2. Specifically, when the SiO2 substrate was deposited by ALD and PFTPA treated compared to Ref, the thickness was reduced to 0.5 nm, but the SiN substrate was reduced to 0.2 nm, so when compared, a difference of about 0.3 nm was shown.

[0061] On the other hand, in the case of the metal substrate that exhibited a water-repellent effect as can be seen in Fig. 4b (see the WCA measurement results in Fig. 2), when the subsequent SiO2 thin film was deposited to a target thickness of 5.0 nm, in the case of the TiN substrate, 3.0 nm was grown on the Ref substrate without PFTPA inhibitor treatment, whereas it grew to 1.9 nm after PFTPA inhibitor treatment, confirming that the thin film thickness decreased due to the inhibitor treatment. In addition, in the case of the W substrate, 3.4 nm was grown on the Ref substrate without PFTPA inhibitor treatment, whereas it grew to 2.3 nm after PFTPA inhibitor treatment, confirming that the thin film thickness decreased due to the inhibitor treatment. In this way, a relatively high selectivity of approximately 3 nm could be secured on the TiN substrate and the W substrate.

[0062] Fig. 5 is a graph showing the results of selective vapor deposition of silicon oxide films using BDIPADS as an aminosilane compound in an ALD process after cleaning with a hydrogen fluoride (HF) solution and treating with an amine-based fluorocarbon inhibitor on SiO2 substrates, SiN substrates, TiN substrates, and W substrates, with the exposure time of the inhibitor adjusted to 10, 30, and 60 seconds, respectively. In this case, Figs. 5a, 5b, and 5c are graphs showing the ALD vapor deposition conditions set to room temperature (RT), 60°C, and 80°C, respectively, to confirm the process conditions that can achieve excellent selectivity.

[0063] As can be seen in Fig. 5a, the results of the experiment at room temperature (RT) did not show any water-repellent properties on the metal substrate even with an exposure time of 60 seconds. However, as can be seen in Fig. 5b, the water-repellent properties of the TiN substrate and the W substrate increased the most rapidly at an exposure time of 30 seconds under the 60°C process condition, confirming that this was the optimal process condition. On the other hand, as can be seen in Fig. 5c, when the process temperature was increased to 80°C, the WCA value on the metal substrate was not superior to that under the 60°C process condition, confirming that the 60°C process condition was ultimately the best.

[0064] Fig. 6 shows a graph and TEM images showing the results of measuring the thickness change of a thin film after cleaning with a hydrogen fluoride (HF) solution on a SiO2 substrate, a TiN substrate, and a W substrate and performing 100 ALD processes (selective vapor deposition of silicon oxide films using BDIPADS as an aminosilane compound) (denoted as “Ref”), and after treating with an amine-based fluorocarbon inhibitor after cleaning and performing 100 ALD processes in the same manner as above (denoted as “PFTPA”). In this case, Figs. 6a, 6b, and 6c differ in that the target thicknesses of the silicon oxide films were set to 5 nm, 7.5 nm, and 10 nm, respectively, and the number of ALD processes was 100 cycles, 188 cycles, and 240 cycles, respectively, depending on the target thickness.

[0065] ALD 1 cycle consists of 60 seconds of PFTPA inhibitor adsorption - 30 seconds of argon purge process - 2 seconds of BDIPADS precursor supply - 30 seconds of argon purge process - 5 seconds of O3 (ozone) plasma - 45 seconds of purge process.

[0066] To observe the selectivity, the deposition was performed in split cycles with 100 cycles, 188 cycles, and 240 cycles, with the 100 cycle targeting SiO25nm growth, the 188 cycle targeting SiO27.5nm growth, and the 240 cycle targeting SiO210nm growth.

[0067] As can be seen in FIGS. 6a to 6c and the results summarized in Table 1, the samples marked as Ref are SiO2 deposited on bare substrates to which PFTPA inhibitor was not applied, and it can be confirmed that the selectivity was maximized on the metal substrate after the application of the PFTPA inhibitor. In the case of 100 cycles with the target thickness of 5 nm, no SiO2 film was deposited on both the TiN and W substrates, so perfect selectivity implementation was possible. In order to observe the extreme maximum selectivity, the result of depositing 10 nm showed that the selectivity of 4.22 nm on the TiN substrate and the selectivity of 4.62 nm on the W substrate were implemented.

[0068] [Table 1]

[0069]

[0070] Figure 7a is a graph showing the results of measuring the change in the thickness of a thin film after preparing a substrate in which a SiO2 substrate and a TiN substrate coexist, cleaning it with a hydrogen fluoride (HF) solution, and performing 100 ALD processes (selective vapor deposition of a silicon oxide film using BDIPADS as an aminosilane compound) (denoted as “Ref 100cy”), and after treating it with an amine-based fluorocarbon inhibitor after cleaning and performing 100 ALD processes in the same manner as above (denoted as “PFTPA 100cy”), and Figure 7b shows a TEM photograph.

[0071] This is an experiment to verify whether or not selectivity can be implemented by fabricating a line-type substrate with its own TiN / SiO2 coexistence. The distance between patterns on the substrate was formed to be 200 micrometers, and the line height was 100 nm. Using the ALD process described in Fig. 6, SiO2 thin film deposition was performed on the substrate with target thicknesses of 1 nm, 2 nm, 3 nm, and 5 nm, respectively. Surface analysis was performed through FIB-TEM cross-sectional analysis, and the results were plotted and shown in Fig. 7a, and the TEM image is shown in Fig. 7b.

[0072] As a result, for target thicknesses of 1 nm, 2 nm, and 3 nm, intrinsic selectivity was achieved due to the surface properties between the substrate itself and the precursor both before and after treatment with the amine-based fluorocarbon inhibitor. However, as can be seen in Fig. 7a, when deposited with a target thickness of 5 nm, a selectivity of 3.64 nm was achieved when the amine-based fluorocarbon inhibitor was not treated, and a selectivity of 5.02 nm was achieved when the amine-based fluorocarbon inhibitor was treated.

[0073] “Bare” in the graph of Fig. 7a means that no treatment has been performed, HF-SiO2 (blanket) means a flat substrate without a pattern after HF solution cleaning treatment, and HF-TiN (pattern) means a substrate on which a pattern has been formed after HF solution cleaning treatment.

[0074] As can be seen in the TEM image of Fig. 7b, no SiO2 thin film was deposited at all when the inhibitor was treated (SiO2 thickness was 0 nm), confirming that SiO2 deposition was completely suppressed on the TiN substrate, which is a non-growth region, by the amine-based fluorocarbon inhibitor treatment.

[0075]

[0076] 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 amine-based fluorocarbon 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), and a tungsten film (W). 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 above non-growth region is at least one of a titanium nitride film (TiN) and a tungsten film (W), and the inhibitor is adsorbed to the non-growth region by a chemisorption method. A method for depositing a silicon oxide film on a semiconductor substrate.

3. In paragraph 1, The above amine fluorocarbon inhibitor comprises at least one compound represented by the following formula 1: A method for depositing a silicon oxide film on a semiconductor substrate. <Formula 1> N{(CF2) n (CF3)}3(n is an integer from 0 to 20) 4. In paragraph 1, The above amine fluorocarbon inhibitor comprises at least one of perfluorotributylamine, perfluorotripentylamine and perfluorotripropylamine. A method for depositing a silicon oxide film on a semiconductor substrate.

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 trimethylsilyldimethylamine (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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