Thin film processing method and method for manufacturing memory element comprising same

Abstract

According to an embodiment of the present invention, a thin film processing method comprises: a step for supplying a surface treatment agent into a chamber in which a substrate is placed, and processing the substrate; a step for purging the inside of the chamber; a step for supplying a precursor into the chamber to adsorb the precursor onto the thin film; a step for purging the inside of the chamber; a step for supplying a reactant material into the chamber to form a thin film; and a step for purging the inside of the chamber.

Description

Thin film processing method and method for manufacturing a memory device including the same

[0001] The present invention relates to a thin film processing method and a method for manufacturing a memory device including the same, and more specifically, to a thin film processing method that can selectively increase the reactivity of a surface through surface treatment to uniformly deposit an atomic layer in a desired area within a three-dimensional structure and improve the characteristics of the thin film, and a method for manufacturing a memory device including the same.

[0002] The primary mechanism of conventional top-down patterning involves depositing a desired material in the form of a thin film and then fabricating it into the desired size and shape through various etching methods. However, this method has the disadvantage of requiring complex process steps, particularly the potential for substrate damage or pattern deformation during the etching process. Furthermore, as pattern sizes become increasingly ultra-fine due to the continuous demand for high performance and low power, and innovations toward multi-dimensional stacked structures beyond the current three dimensions are required, conventional top-down patterning has been identified as a limitation in the evolution of miniaturization processes.

[0003] To address this, a technology is being developed to create patterns using a bottom-up patterning method that selectively deposits material only in desired areas by utilizing Area-Selective Atomic Layer Deposition (AS-ALD) based on self-aligned fabrication. This AS-ALD technology not only reduces manufacturing costs by mitigating Edge Placement Errors (EPE), the biggest drawback of conventional top-down patterning, but also enables the creation of more precise patterns in complex structures through its self-aligned fabrication process.

[0004] Area-selective deposition (GCD) technology involves the development of various methods, such as using precursors that grow only in the growth region, activating the growth region, and blocking non-growth regions; however, these methods require a high level of technical difficulty. In particular, as the process is repeated, the initial surface state gradually changes, resulting in a loss of selectivity, and there is a continuous demand for methods to improve this.

[0005] The objective of the present invention is to provide a thin film treatment method capable of improving the characteristics of a thin film through surface treatment, and a method for manufacturing a memory device including the same.

[0006] Other objects of the present invention will become more apparent from the following detailed description.

[0007] According to one embodiment of the present invention, a thin film treatment method comprises the steps of: supplying a surface treatment agent into the interior of a chamber on which a substrate is placed to treat the substrate; purging the interior of the chamber; supplying a precursor into the interior of the chamber to adsorb the precursor onto the thin film; purging the interior of the chamber; supplying a reaction material into the interior of the chamber to form a thin film; and purging the interior of the chamber, wherein the surface treatment agent is represented by the following <Chemical Formula 1> or the following <Chemical Formula 2>.

[0008] <Chemical Formula 1>

[0009]

[0010] <Chemical Formula 2>

[0011]

[0012] In the above <Chemical Formula 1> or <Chemical Formula 2>,

[0013] X1 to X2 may each be the same or different from one another and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and

[0014] R1 to R3 may each be the same or different from one another and are independently selected from hydrogen, linear, branched, or cyclic alkyl groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, hydroxyl groups having 0 to 4 carbon atoms, and alkoxy groups having 0 to 4 carbon atoms.

[0015] The above surface treatment agent may be either Dichloromethyl methyl ether (DCMME) or 1-chloromethyl ethyl ether (1-CMEE).

[0016] The above reaction substance may be any one of O3, O2, or H2O.

[0017] The above thin film can have one of Al, Ti, Hf, Nb, Ta, Mo, W, Zr, Ru, Sn, and Cr as the central element.

[0018] The above thin film may be any one of a metal film, a metal oxide, a metal nitride, a metal sulfide, a silicon nitride, or a silicon oxide.

[0019] The metal film may be a binary compound or a ternary compound doped with one or more elements.

[0020] The above thin film treatment method can be carried out at 50 to 700 ℃.

[0021] According to one embodiment of the present invention, a method for manufacturing a volatile memory device may include the capacitor manufacturing method described above.

[0022] According to one embodiment of the present invention, a method for manufacturing a non-volatile memory device may include the capacitor manufacturing method described above.

[0023] According to one embodiment of the present invention, by supplying a chlorine treatment agent to the surface, surface reactivity is increased and the adsorption of precursors is promoted in the growth region through a cleaning effect that removes oxides from the surface, while in the non-growth region, the surface is chlorinated to reduce reactivity and hinder the adsorption of precursors. Therefore, selective deposition can be achieved in the growth region and the non-growth region, and precise patterns can be created in complex structures by using it as a method of bottom-up patterning.

[0024] FIG. 1 is a diagram showing a thin film processing method according to an embodiment of the present invention.

[0025] FIG. 2 is a graph schematically showing the supply cycle according to an embodiment of the present invention.

[0026] FIG. 3 is a graph showing the Nb content of a substrate according to a comparative example / example of the present invention.

[0027] FIGS. 4 and FIGS. 5 are graphs showing the surface elemental composition of each substrate according to the comparative example / exemplar of the present invention.

[0028] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the attached FIGS. 1 to 5. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be interpreted as being limited to the embodiments described below. These embodiments are provided to further explain the present invention in detail to those skilled in the art to which the invention pertains. Accordingly, the shape of each element shown in the drawings may be exaggerated to emphasize a clearer explanation.

[0029] FIG. 1 is a flowchart illustrating a thin film processing method according to an embodiment of the present invention, and FIG. 2 is a graph schematically illustrating a supply cycle according to an embodiment of the present invention. A substrate is loaded into the interior of a process chamber, and the following process conditions may be adjusted. Process conditions may include the temperature of the substrate or the process chamber, chamber pressure, and gas flow rate, and the temperature is 50 to 700°C.

[0030] The substrate is exposed to a surface treatment agent supplied inside the chamber, and the substrate is treated through the surface treatment agent. The surface treatment agent is represented by the following <Chemical Formula 1> or the following <Chemical Formula 2>.

[0031] <Chemical Formula 1>

[0032]

[0033] <Chemical Formula 2>

[0034]

[0035] In the above <Chemical Formula 1> or <Chemical Formula 2>,

[0036] X1 to X2 may each be the same or different from one another and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and

[0037] R1 to R3 may each be the same or different from one another and are independently selected from hydrogen, linear, branched, or cyclic alkyl groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, hydroxyl groups having 0 to 4 carbon atoms, and alkoxy groups having 0 to 4 carbon atoms.

[0038] Specifically, the surface treatment agent may be either Dichloromethyl methyl ether (DCMME) or 1-chloromethyl ethyl ether (1-CMEE).

[0039] Afterward, a purge gas (an inert gas such as Ar) is supplied into the chamber to remove or purify unadsorbed surface treatment agents or byproducts. The above process corresponds to the first cycle (1st cycle) illustrated in FIGS. 1 and 2, and the following process corresponds to the second cycle (2nd cycle) illustrated in FIGS. 1 and 2.

[0040] Subsequently, the substrate is exposed to a precursor supplied into the chamber, and the precursor is adsorbed onto the substrate. The precursor may have one of Al, Ti, Hf, Nb, Ta, Mo, W, Zr, Ru, Sn, or Cr as the central element. At this time, the precursor supply step is carried out at 50 to 700 ℃.

[0041] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed precursors or byproducts.

[0042] Subsequently, the substrate is exposed to a reactive material (or reactive gas) supplied inside the chamber, and etching is activated simultaneously with the formation of a thin film by the reactive material. The reactive material may be any one of O3, O2, or H2O.

[0043] The thin film may have one of Al, Ti, Hf, Nb, Ta, Mo, W, Zr, Ru, Sn, or Cr as the central element. Specifically, the thin film may be any one of a metal film, a metal oxide, a metal nitride, a metal sulfide, a silicon nitride, or a silicon oxide, and the thin film may be a binary compound or a ternary compound doped with one or more elements.

[0044] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove unreacted substances or byproducts or to purify the chamber.

[0045]

[0046] - Comparative Example - MOx ALD

[0047] Niobium precursors were deposited on SiCN substrates (non-metallic thin film, non-growth region) and TiN substrates (metallic thin film, growth region), respectively, using an ALD process at a process temperature of 340 ℃ and O3 gas as the reactant.

[0048] The niobium precursor supply process is as follows.

[0049] 1) Using Ar as a carrier gas, the niobium precursor EtMeCp-Nb=NtBu(Cl)2 is supplied to the reaction chamber and the niobium precursor is adsorbed onto the SiCN substrate / TiN substrate.

[0050] 2) Supply Ar gas into the reaction chamber to remove unadsorbed niobium precursors or byproducts

[0051] 3) Supply O3 gas to the reaction chamber to form a niobium oxide film.

[0052] 4) Supply Ar gas into the reaction chamber to remove unreacted materials or byproducts

[0053] When the above process was repeated, the niobium content was confirmed to be 2.35% (TiN substrate) and 0.72% (SiCN substrate), and the selectivity ratio was confirmed to be 3.3:1 (see Fig. 3).

[0054]

[0055] - Examples - Cl Surface Treatment + MOx ALD

[0056] In the first cycle, the surfaces of the SiCN substrate (non-metallic thin film, non-growth region) and the TiN substrate (metallic thin film, growth region) were activated through a Cl surface treatment process. The process temperature was 340 ℃.

[0057] In the second cycle, a niobium precursor was deposited on a SiCN substrate (non-metallic thin film, non-growth region) and a TiN substrate (metallic thin film, growth region), respectively, using an ALD process, with a process temperature of 340 ℃ and O3 gas as the reactant.

[0058] The surface treatment agent and niobium precursor supply process is as follows, and the steps 1)-2) below were carried out as the first cycle and the steps 3)-6) as the second cycle (refer to Figs. 1 and 2).

[0059] 1) Supply the surface treatment agent DCMME to the reaction chamber and activate the SiCN substrate / TiN substrate surface.

[0060] 2) Supply Ar gas into the reaction chamber to remove unadsorbed surface treatment agents or byproducts

[0061] 3) Using Ar as a carrier gas, the niobium precursor EtMeCp-Nb=NtBu(Cl)2 is supplied to the reaction chamber and the niobium precursor is adsorbed onto the SiCN substrate / TiN substrate.

[0062] 4) Supply Ar gas into the reaction chamber to remove unadsorbed niobium precursors or byproducts

[0063] 5) Supply O3 gas to the reaction chamber to form a niobium oxide film.

[0064] 6) Supply Ar gas into the reaction chamber to remove unreacted materials or byproducts

[0065] When the second cycle was repeated after the first cycle, the niobium content was confirmed to be 2.73% (TiN substrate) and 0.09% (SiCN substrate), and the selectivity ratio was confirmed to be 30.3:1 (see Fig. 3).

[0066] In conclusion, when comparing the selectivity of the comparative example and the example, it can be seen that the selectivity was improved by about 10 times as Nb was reduced by about 88% in the non-growth region of the SiCN substrate.

[0067] Table 1 below shows the Nb content of each substrate in the comparative example / example, and Figure 3 is a graph showing the Nb content of the substrate according to the comparative example / example of the present invention.

[0068] Item Cl Surface Treatment SDAN b% @XPSTemp.Surface Treatment Agent Temp.Precursor On TiNOn SiCN Selectivity Ratio Comparison Example XX340EtMeCpNb=NtBu(Cl)22.35 0.72 3.3 : 1 Example 340DCMME340EtMeCpNb=NtBu(Cl)22.73 0.093 0.3 : 1

[0069] In addition, XPS analysis of the surface elemental composition before and after the surface treatment process reveals that Cl is not detected and impurities such as O and C are confirmed at equivalent levels, so there is no concern regarding degradation caused by the surface treatment process.

[0070] Table 2 below shows the surface elemental composition of each substrate in the comparative example / example, and Figures 4 and 5 are graphs showing the surface elemental composition of each substrate according to the comparative example / example of the present invention.

[0071] Item Cl Surface Treatment SDAT iNS iCN Temp.Surface Treatment Agent Temp.Precursor O%C%Cl%O%C%Cl%Comparative Example XX340EtMeCpNb=NtBu(Cl)229.420.94019.912.390Example 340DCMME340EtMeCpNb=NtBu(Cl)222.2626.98019.329.770

[0072] Meanwhile, the growth region described above may be a titanium nitride film or a niobium nitride film. Additionally, the non-growth region described above may be a silicon nitride film, and the silicon nitride film may be one or more selected from SiN, SiCN, C-doped SiN, and SiON.

[0073] Although the present invention has been described in detail through embodiments above, other forms of embodiments are also possible. Therefore, the technical concept and scope of the claims described below are not limited to the embodiments.

Claims

1. A step of treating the substrate by supplying a surface treatment agent into the interior of a chamber on which the substrate is placed; A step of purging the interior of the above chamber; A step of supplying a precursor to the interior of the chamber and adsorbing the precursor onto the thin film; A step of purging the interior of the above chamber; A step of supplying a reaction material into the interior of the chamber to form a thin film; and It includes a step of purging the interior of the chamber, A thin film treatment method wherein the above surface treatment agent is represented by the following <Chemical Formula 1> or the following <Chemical Formula 2>. <Chemical Formula 1> <Chemical Formula 2> In the above <Chemical Formula 1> or <Chemical Formula 2>, X1 to X2 may each be the same or different from one another and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and R1 to R3 may each be the same or different from one another and are independently selected from hydrogen, linear, branched, or cyclic alkyl groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, hydroxyl groups having 0 to 4 carbon atoms, and alkoxy groups having 0 to 4 carbon atoms.

2. In Paragraph 1, A thin film treatment method in which the above-mentioned surface treatment agent is either Dichloromethyl methyl ether (DCMME) or 1-chloromethyl ethyl ether (1-CMEE).

3. In Paragraph 1, A thin film treatment method in which the above reaction material is any one of O3, O2, or H2O.

4. In Paragraph 1, The above thin film is a thin film treatment method having one of Al, Ti, Hf, Nb, Ta, Mo, W, Zr, Ru, Sn, and Cr as a central element.

5. In Paragraph 1, A thin film treatment method in which the above thin film is any one of a metal film, a metal oxide, a metal nitride, a metal sulfide, a silicon nitride, or a silicon oxide.

6. In Paragraph 5, A thin film treatment method in which the thin film is a binary compound or a ternary compound doped with one or more elements.

7. In Paragraph 1, The above thin film treatment method is a thin film treatment method carried out at 50 to 700 ℃.

8. A method for manufacturing a volatile memory device comprising the thin film processing method described in claim 1.

9. A method for manufacturing a non-volatile memory device comprising the thin film processing method described in claim 1.

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