Method for forming electrode of semiconductor device

Abstract

The method for forming an electrode according to an embodiment of the present invention may include preparing a substrate, spraying a precursor containing ruthenium (Ru) onto the substrate to form a metal thin film layer, a first process of spraying a first processing gas containing oxygen (O2) onto the substrate, a purging process of spraying a purging gas after stopping the spraying of the first processing gas, and a second process of spraying a second processing gas containing at least one of hydrogen (H2), argon (Ar), and helium (He) onto the substrate to anneal the metal thin film layer. Therefore, according to an embodiment of the present invention, an electrode in which coordination group impurities arising from a precursor containing at least one of ruthenium (Ru) and molybdenum (Mo) are removed can be formed. Therefore, an electrode with low resistance can be prepared. Furthermore, when forming an electrode on a substrate having trenches, step coverage can be improved by reducing the difference between the thickness of the thin film formed on the inner wall of the trench and the thickness of the thin film formed on the upper surface of the substrate.

Description

Method for forming an electrode of a semiconductor device The present invention relates to a method for forming an electrode of a semiconductor device, and more particularly to a method for forming an electrode of a semiconductor device with improved electrical properties. In order to improve the electrical properties of semiconductor devices such as NAND flash, it is necessary to reduce the resistance of electrodes. When forming an electrode of a semiconductor device, the electrode may be formed by spraying a metal precursor onto a substrate and depositing the metal precursor onto the substrate. Meanwhile, the precursor used to form the electrode contains at least one ligand selected from carbon (C), hydrogen (H), and oxygen (O). However, these ligands act as impurities that increase the resistance of the electrode, thereby degrading the electrical properties of the semiconductor device. [Related technical documents] [Patent Document] (Patent Document 1) Korean Patent No. 10-0942958 The present invention provides a method for forming an electrode of a semiconductor device, the method being capable of reducing the resistance of the electrode. The present invention also provides a method for forming an electrode of a semiconductor device, the method being capable of removing impurities. According to an exemplary embodiment, a method for forming an electrode includes the steps of preparing a substrate, spraying a precursor containing ruthenium (Ru) on the substrate to form a metal thin film layer, and spraying a precursor containing oxygen (O 2) of the first processing gas sprayed onto the substrate, a purge step of spraying a purge gas after stopping the spraying of the first processing gas, and a purge step of spraying a purge gas containing hydrogen (H 2) A second processing step in which at least one of argon (Ar) and helium (He) is sprayed onto the substrate to anneal the metal thin film layer. The method may further include a first plasma treatment step performed after the first treatment step and forming an oxygen (O) plasma on the substrate. The method may further include a first plasma treatment step performed before the first treatment step and forming an oxygen (O) plasma on the substrate. The step of forming the metal thin film layer, the first treatment step, the blowing step, and the second treatment step may be repeated and performed a plurality of times. The process temperature of the second treatment step may be adjusted to be higher than the process temperature of the first treatment step. The pressure of the second processing step may be from about 5 Torr to about 7 Torr. According to an exemplary embodiment of the present invention, a substrate may include a groove recessed downward from its upper surface, and according to an exemplary embodiment of the present invention, a method for forming an electrode may further include a pre-treatment step, wherein the pre-treatment step exposes the substrate having a metal film layer formed thereon to oxygen plasma to convert a portion of the metal film layer into gaseous metal oxide, thereby etching the metal film layer, wherein the pre-treatment step may be performed between the first treatment step and the blowing step, or between the step of forming the metal film layer and the first treatment step. When a portion of the metal film layer is converted into gaseous metal oxide in the pre-treatment step, another portion of the metal film layer may be converted into solid metal oxide, and the second treatment gas sprayed in the second treatment step may contain hydrogen (H 2), and spraying containing hydrogen (H 2) The second processing step of the second processing gas can make the hydrogen (H 2) reacting with the solid metal oxide contained in the metal film layer, thereby reducing the solid metal oxide to metal. The second treatment step may comprise treating the 2) a step of generating hydrogen plasma by using a second processing gas. According to another exemplary embodiment, a method for forming an electrode includes the steps of preparing a substrate on one surface of which an indium gallium zinc oxide (IGZO) thin film layer is formed, spraying a precursor containing ruthenium (Ru) on the IGZO thin film layer to form a metal thin film layer, and spraying a precursor containing oxygen (O 2) a first processing step of spraying a first processing gas onto the substrate to remove impurities contained in the metal film layer, a blowing step of spraying a blowing gas after stopping the spraying of the first processing gas, and a second processing step of spraying a second processing gas containing argon (Ar) onto the substrate to anneal the metal film layer. The method may further comprise performing, after the second treatment step, a step of treating the gas containing hydrogen (H 2) A post-processing step in which the post-processing gas is sprayed onto the substrate. According to yet another exemplary embodiment, a method for forming an electrode includes a step of preparing a substrate, a first process cycle step including a step of forming a first metal film layer on the substrate, and a second process cycle step including a step of forming a second metal film layer on the first metal film layer, wherein the first process cycle step includes a step of spraying a precursor containing ruthenium (Ru) onto the substrate to form the first metal film layer, a step of spraying a precursor containing oxygen (O 2) on the substrate, a purge step of spraying a purge gas after stopping the spraying of the first process gas, and a second process step of spraying a second process gas containing argon (Ar) on the substrate, and the second process cycle step includes spraying a precursor containing ruthenium (Ru) on the first metal film layer to form a second metal film layer, spraying a precursor containing oxygen (O 2) on the first metal film layer, a third treatment step of spraying the third treatment gas on the first metal film layer, a purge step of spraying the purge gas after stopping the spraying of the third treatment gas, and a purge step of spraying the purge gas containing hydrogen (H 2) a fourth processing step of spraying the fourth processing gas onto the first metal film layer. The fourth process step may include a step of spraying a gas containing argon (Ar) before spraying the fourth process gas. Below, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided solely to complete the present invention and to fully convey the scope of the present invention to those skilled in the art. The drawings may be exaggerated in depicting embodiments of the present invention, and similar reference numerals in the drawings indicate similar elements. Embodiments of the present invention relate to a method for forming an electrode for a semiconductor device, and more particularly, to a method for forming an electrode for a semiconductor device with improved electrical properties. More specifically, embodiments of the present invention relate to a method for forming an electrode for a semiconductor device, including a method for forming a low-resistance metal thin film layer. As a specific example, the semiconductor device may be an NAND flash, and the electrode may be the gate electrode of the NAND flash. However, the electrode formed by the method according to the embodiment is not limited to a gate electrode and can be various components requiring conductivity, such as a word line of the NAND flash. Furthermore, the electrode formed by the method according to the embodiment is not limited to NAND flash and can be applied to thin films requiring conductivity in various semiconductor devices. [Example 1] FIG. 1 is a diagram illustrating a state in which electrodes are formed on a substrate according to an exemplary embodiment. 1 , the electrode 100 may be formed on a substrate S. Here, the substrate S may be a wafer selected from the group consisting of a Si wafer, a gallium arsenide (GaAs) wafer, and a silicon germanium (SiGe) wafer. The electrode 100 may be a laminate body formed by stacking a plurality of metal thin film layers 110. Furthermore, each of these metal thin film layers 110 may be formed using a precursor material containing ruthenium (Ru), a low-resistance metal. Therefore, the electrode 10 may be an electrode containing or made of ruthenium (Ru). In addition, the metal thin film layer 110 may be formed by using a precursor material containing molybdenum (Mo). Therefore, the electrode 100 may be an electrode containing molybdenum (Mo). In addition, the metal thin film layer 110 may be formed by using a precursor material including ruthenium (Ru) and molybdenum (Mo), and thus the electrode 100 may be an electrode including ruthenium (Ru) and molybdenum (Mo). Hereinafter, referring to FIG. 1 to FIG. 3 , a method for forming an electrode on a substrate according to an exemplary embodiment will be described. Fig. 2 is a conceptual diagram for describing a method for forming an electrode according to an exemplary embodiment. Fig. 3 is a process diagram conceptually illustrating a method for forming an electrode according to an exemplary embodiment. In FIG. 2 , the term “ON” may mean that a raw material for a process is sprayed, and the term “OFF” may mean that the spraying of the raw material is stopped or terminated. 2 and 3 , the method for forming the electrode 100 includes spraying a precursor comprising at least one of ruthenium (Ru) and molybdenum (Mo) toward the substrate S to form the metal film layer 110 (precursor spraying step P). pr ), spray containing oxygen (O 2) (hereinafter referred to as the first processing gas) to remove impurities from the metal film layer 110 (the first processing step P t1 ), and spraying containing hydrogen (H 2) an annealing step (second processing step P) of at least one of argon (Ar) and helium (He) to increase the temperature inside the chamber where the process is performed and thereby reduce the voids in the metal film layer 110. t2 ). In addition, the method for forming the electrode 100 may include a step of spraying a purge gas. That is, the method may include a precursor spraying step P pr and impurity removal step (first processing step P t1 ) between the first purge step P of spraying purge gas pu1, in the impurity removal step (first processing step P t1 ) and annealing step (second processing step P t2 ) between the second blowing step P of spraying blowing gas pu2 , and in the annealing step (second processing step P t2 ) after the termination of the third purge step P spraying purge gas pu3 . In summary, the method for forming the electrode 100 may include a precursor spraying step P pr , the first blowing step P pu1 , impurity removal step (first processing step P t1 ), the second blowing step P pu2 , annealing step (second processing step P t2 ) and the third blowing step P pu3 . In addition, the precursor spraying step P pr - First blowing step P pu1 -Impurity removal step (first treatment step P t1 )-Second blowing step P pu2 - Annealing step (second treatment step P t2 )-third blowing step P pu3 A process cycle CY can be set to form a metal thin film layer 110. Furthermore, as shown in FIG1 , the process cycle CY is repeated multiple times to deposit or stack multiple metal thin film layers 110. Thus, an electrode 100 stacked with these metal thin film layers 110 or an electrode 100 of a semiconductor device including these metal thin film layers 110 is formed. At this time, the number of repetitions of the process cycle CY can be adjusted according to the target thickness of the electrode 100 to be formed. In the above, it has been described that a process cycle CY includes all the first purge steps P pu1 , the second blowing step P pu2, the third blowing step P pu3 However, it is not limited to this, and the first blowing step P may be performed. pu1 , the second blowing step P pu2 , the third blowing step P pu3 Some steps in the above method are omitted, and other steps can be omitted. At this time, it is preferred to perform the second blowing step P pu2 , and omit the first blowing step P pu1 And the third blowing step P pu3 At least one of . In FIG. 1 , in order to distinguish a plurality of metal thin film layers formed by a plurality of process cycles CY, each metal thin film layer 110 is illustrated separately. However, the stacked metal thin film layers 110 may be in a single body. In addition, each "step" included in a process cycle CY can be expressed as a "process". That is, the process cycle CY can be described as including "precursor spraying process P pr -First blow-off process P pu1 -Impurity removal process (first treatment process P t1 )-Second blow-off process P pu2 - Annealing process (second treatment process P t2 )-Third blow-off process P pu3 ". Hereinafter, each step included in the process cycle CY will be described in detail. 2) Step P of removing impurities by first treating gas t1 It will be named and described as "the first processing step P t1 ". In addition, spraying contains H 2. Step P of annealing the metal film layer 110 using a second process gas of at least one of Ar and He. t2 The second processing step will be named and described as t2 ". In the precursor spraying step P pr In the process, a precursor raw material containing at least one of ruthenium (Ru) and molybdenum (Mo) is sprayed into a chamber loaded with a substrate S. For example, the precursor material containing ruthenium (Ru) may be bis(ethylcyclopentadienyl)ruthenium (EtCp) 2Ru) source. Furthermore, for example, the precursor source containing molybdenum (Mo) may be a source containing at least one of molybdenum hexacarbonyl and molybdenum pentachloride. Herein, the precursor source containing ruthenium (Ru) may be referred to as a "source containing ruthenium (Ru)," and the precursor source containing molybdenum (Mo) may be referred to as a "source containing molybdenum (Mo)." The precursor raw material containing at least one of ruthenium (Ru) and molybdenum (Mo) can be an organic substance. In addition, the precursor raw material can be solid or liquid. Therefore, the solid or liquid precursor is heated and converted into a gas before being sprayed, and then the gaseous precursor is sprayed onto the substrate S. When the precursor is sprayed toward the substrate S, the precursor or metal element contained in the precursor (that is, at least one of ruthenium (Ru) and molybdenum (Mo)) is adsorbed on the substrate S. Therefore, as shown in (a) in Figure 3, a metal film layer 110 is formed on the substrate S. That is, a metal film layer 110 containing at least one of ruthenium (Ru) and molybdenum (Mo) is formed. When the current drive body spraying step P pr At the end, the purge gas is sprayed into the cavity and blown away (the first purge step P pu1 ) At this time, for example, Ar gas can be used as the purge gas. Meanwhile, the precursor material containing at least one of ruthenium (Ru) and molybdenum (Mo) may contain at least one ligand among carbon (C), hydrogen (H), and oxygen (O), depending on the type of material. Therefore, the metal thin film layer 110, on which the precursor material containing at least one of ruthenium (Ru) and molybdenum (Mo) is sprayed and deposited, may contain at least one ligand among carbon (C), hydrogen (H), and oxygen (O). Furthermore, the ligands, such as carbon (C), hydrogen (H), and oxygen (O), contained in the metal thin film layer 110 act as impurities that increase resistance. Therefore, in this embodiment, after the precursor is sprayed to form the metal film layer 110, a step of removing the impurities serving as at least one ligand among carbon (C), hydrogen (H) and oxygen (O) impurities from the metal film layer 110 is performed, that is, the first treatment step P t1 . Hereinafter, the first processing step P will be described. t1 . First processing step P t1 This is a step of removing impurities from the metal film layer 110. The first processing step P t1 Contains will contain oxygen (O 2) The first processing gas is sprayed into the chamber. Here, oxygen (O 2) The first processing gas may be, for example, pure oxygen (O 2), or air. However, it is not limited thereto, and various The gas of 2) can be used as the first process gas. In the precursor spraying step P pr and the purge gas spraying step (the first purge step P pu1 ) is terminated and then the first processing step P is performed t1 In other words, the precursor spraying step P is performed sequentially. pr and the purge gas spraying step (the first purge step P pu1 ), and the first processing step P can be performed by spraying the first processing gas t1 . The interior of the chamber in which the substrate S is loaded or the process is performed is heated to a predetermined temperature or higher. That is, the interior of the chamber may be in a state where the process temperature for forming the metal film layer 110 is maintained, for example, at about 200°C to about 400°C. More specifically, the temperature inside the chamber may be controlled to be maintained at about 250°C to about 300°C. When the first processing gas is sprayed into the chamber, the ligands, such as carbon (C) ligands, contained in the metal film layer 110 react with oxygen (O 2) reaction. That is, the combustion reaction will occur in the oxygen (O 2) and carbon (C) ligands, thereby separating carbon (C) from the metal thin film layer 110. In other words, the carbon (C) ligand bonds contained in the precursor of the metal thin film layer 110 are broken and fall off from the metal thin film layer 110. Therefore, the content of at least one of the ligand impurities of carbon (C), hydrogen (H), and oxygen (O) contained in the metal thin film layer 110 can be reduced, or the ligand impurities can be removed from the metal thin film layer 110. As described above, in the first process step, the temperature inside the chamber is maintained at about 200° C. to about 400° C., preferably about 250° C. to about 300° C. Therefore, the oxygen (O 2) and the combustion reaction between the ligand. That is, the heat inside the chamber can promote the oxygen (O 2) and the combustion reaction between the ligands contained in the metal thin film layer 110. Therefore, the oxygen (O 2) The combustion reaction between the ligands contained in the metal thin film layer 110 or the precursor can be described as a thermal reaction. In the first process step P t1 After the termination, the purge gas is sprayed into the cavity and blown away (second purge step P pu2 ). At this time, the purge gas can be used in conjunction with the first purge step P pu1 The same gas is used in, for example, Ar gas can be used. Second processing step P t2 The second processing step P can be a process of annealing the metal film layer 110 to reduce the gap. t2 The method comprises the step of spraying a second processing gas into the chamber. In this case, the second processing gas may include hydrogen (H 2) At least one gas selected from argon (Ar) and helium (He). When the second process gas is sprayed into the chamber, the spraying is performed so that the pressure within the chamber increases compared to the pressure within the chamber before the second process gas is sprayed. Preferably, the pressure within the chamber increases to about 5 Torr to about 7 Torr, and the second process gas is sprayed for at least 10 seconds. The reason for spraying the second process gas to increase the chamber internal pressure to approximately 5 Torr to approximately 7 Torr is to increase the chamber internal temperature. For example, before spraying the second process gas or during the first process step, the chamber internal temperature may be approximately 250°C to approximately 300°C. Subsequently, when the second process gas is sprayed to increase the chamber internal pressure to approximately 5 Torr to approximately 7 Torr, the chamber internal temperature may increase to approximately 350°C to approximately 400°C. In other words, the pressure increase caused by spraying the second process gas may increase the chamber internal temperature. Furthermore, because the pressure is increased to approximately 5 Torr to approximately 7 Torr, the chamber internal temperature during the second process step can be controlled to be higher than the chamber internal temperature during the first process step. As the temperature inside the chamber increases, the substrate S or the metal film layer 110 deposited thereon anneals. Consequently, the crystal grains within the metal film layer 110 expand, reducing or narrowing the gaps between the crystal grains. Because the gaps are reduced during annealing, the resistance of the metal film layer 110 or electrode 100 may decrease. This results in a metal film layer 110 or electrode 100 with low resistance. Meanwhile, when the second process gas is sprayed, if the spraying is performed so that the pressure inside the chamber becomes less than 5 Torr, the grains of the metal thin film layer 110 may not expand or may not expand to a sufficient extent due to the low temperature inside the chamber. For example, the temperature inside the chamber may be lower than about 350°C so that the grains of the metal thin film layer 110 may not expand or may not expand to a sufficient extent. In addition, in order to expand the grains of the metal thin film layer 110, the temperature inside the chamber is controlled to about 350°C to about 400°C, and for this purpose, a pressure of about 7 Torr or less is sufficient. Therefore, when the second process gas is sprayed, the pressure inside the chamber is controlled to be about 5 Torr to about 7 Torr. As mentioned above, the second process gas used in the second process step contains hydrogen (H 2) At least one of argon (Ar) and helium (He). 2) is used as the second process gas, the impurities remaining in the metal thin film layer 110 can be further removed in the second process step. That is, in the metal thin film layer 110, at least one of the ligand impurities of carbon (C), hydrogen (H), and oxygen (O) that were not removed in the first process step may remain. The hydrogen (H) contained in the second process gas 2) can further remove ligand impurities. In other words, the hydrogen (H 2) At least one ligand bond of carbon (C), hydrogen (H), and oxygen (O) contained in the metal thin film layer 110 can be broken and removed. As a result, at least one of the ligand impurities of carbon (C), hydrogen (H), and oxygen (O) contained in the metal thin film layer 110 can have a reduced content or be removed. Second processing step P t2 The step of generating plasma may be included. That is, the second processing step P t2 The step of generating plasma by using the second process gas while spraying the second process gas may be included. More specifically, the second process gas is sprayed into the chamber or toward the substrate S, and power is supplied for generating plasma. At this time, for example, radio frequency (RF) power is applied to at least one of the chamber, the susceptor on which the substrate S is placed inside the chamber, and the spraying unit for spraying the second process gas into the chamber. Thus, a plasma containing hydrogen (H2) may be generated inside the chamber. 2) Plasma of at least one of argon (Ar) and helium (He). The plasma can promote the annealing of the metal film layer 110. In other words, compared with the case where the second process gas is sprayed without generating plasma, when the plasma is generated while the second process gas is sprayed, the annealing reaction can occur faster to shorten the annealing time. In the second process step P t2 After the termination, the purge gas is sprayed into the cavity and blown away (third purge step P pu3 ). At this time, the purge gas can be used in conjunction with the first purge step P pu1 And the second blowing step P pu2 The same gas is used in, for example, Ar gas can be used. Hereinafter, the process comprising the "precursor spraying step P pr - First blowing step P pu1 - First processing step P t1 - Second blowing step P pu2 - Second processing step P t2 - The third blowing step P pu3The process cycle CY can be repeated multiple times. Therefore, as shown in FIG1 , a plurality of metal thin film layers 110 are formed on the substrate S, and thus an electrode 100 having a predetermined thickness is formed. [Example 2] FIG. 4 is a conceptual diagram illustrating a method of forming a metal thin film layer on a substrate according to another exemplary embodiment. In FIG4 , the term “ON” may refer to spraying a material for a process or generating plasma, and the term “OFF” may refer to stopping or terminating the spraying of the material or the generation of plasma. The method according to another exemplary embodiment may be combined with the precursor spraying step P pr The method of the exemplary embodiment is the same as that of the embodiment of the present invention, and the first blowing step P pu1 , the second blowing step P pu2 , the third blowing step P pu3 and the second processing step P t2 Can be different from the first processing step P t1 . According to another exemplary embodiment, a first processing step P t1 The process may include the step of generating plasma. That is, as shown in FIG4 , the first processing step P t1 It may include the step of spraying a first processing gas, and the step of generating oxygen plasma using the sprayed first processing gas. More specifically, the first processing gas is sprayed into the cavity or toward the substrate S, and a power source for generating plasma is supplied. At this time, for example, a radio frequency (RF) power source is applied to at least one of the cavity, the base on which the substrate S is provided inside the cavity, and the spraying portion for spraying gas into the cavity. At this time, it is preferred that the power source applied for plasma generation is controlled to be about 500 W to about 1000 W (about 500 watts to about 1000 watts). Therefore, plasma is generated inside the cavity. At this time, because the first processing gas contains oxygen (O 2), so the plasma generated in the first processing step can be "oxygen plasma". When oxygen plasma is generated in the first processing step P t1 When the metal film layer 110 is in the presence of ligand impurities and oxygen (O That is, since the temperature inside the chamber is maintained at about 250°C to about 300°C, the heat inside the chamber causes the ligand impurities and oxygen (O 2) and because oxygen plasma is generated on the top of the reaction, it can promote the combustion reaction between ligand impurities and oxygen (O 2). Therefore, when plasma is generated while spraying the first process gas, at least one of the amount of impurities removed and the rate of impurity removal can be increased compared to spraying only the first process gas. Consequently, ligand impurities generated by the precursor can be removed more effectively. At the same time, when applied to the first processing step P t1 When the power supply in the process is less than 500 W, the effect of promoting the combustion reaction by oxygen plasma may not be significant. t1 When the power supply rate is higher than 1000 W, the metal film layer 110 is converted into RuO The amount of gaseous or vapor-phase metal oxide in the 4 (gas) can be large, and the metal film layer 110 can be etched in large quantities. Therefore, when forming the electrode 100 by stacking multiple metal film layers 110 by performing the process cycle CY multiple times, there may be a problem that it takes a long time to form the electrode 100 to the target thickness. Therefore, in the first processing step P t1 In the embodiment, a power supply of about 500 W to about 1000 W is applied to generate oxygen plasma. [Example 3] Fig. 5 is a process diagram conceptually illustrating a method for forming an electrode according to yet another exemplary embodiment. Fig. 6 is a conceptual diagram for describing a method for forming an electrode according to yet another exemplary embodiment. In FIG6 , the term “ON” may refer to spraying a material for a process or generating plasma, and the term “OFF” may refer to stopping or terminating the spraying of the material or the generation of plasma. In the above exemplary embodiment and another exemplary embodiment, the electrode 100 is formed by depositing the metal film layer 110 on a flat substrate S. However, the present invention is not limited thereto. As shown in FIG5 , the electrode 100 can be formed by depositing the metal film layer 110 on a substrate S having a trench TR. Meanwhile, as shown in FIG. 5( a ), when the metal film layer 110 is formed on the substrate S having the trench TR, an overhang problem may occur, wherein the thickness T of the metal film layer 110 deposited on the upper surface of the substrate S is 1 is greater than the thickness T of the metal thin film layer 110 deposited on the inner wall surface forming the trench TR 2. T 3. In other words, when the precursor sprays step P pr And the first processing step P t1 At the end, the thickness of the metal thin film layer 110 deposited on the substrate S can be changed for each position. At this time, as shown in FIG5 (a), the thickness T deposited on the upper surface of the substrate S is 1 may be different from the thickness T deposited on the inner wall surface forming the trench TR 2. T 3. Therefore, when forming the electrode 100 by depositing the metal thin film layer 110 on the substrate S having the trench TR, it is necessary to reduce the overhang or prevent the overhang from occurring. When the metal film layer 110 is deposited by a method according to yet another embodiment, the overhang can be reduced or prevented. That is, by reducing the thickness T of the metal film layer 110 deposited on the inner wall surface forming the trench TR, the overhang can be reduced or prevented. 2. T 3 and the thickness T of the metal thin film layer 110 deposited on the upper surface of the substrate S 1, which can improve step coverage. 5 and 6 , a method for forming an electrode according to yet another exemplary embodiment will be described. 6, according to yet another exemplary embodiment, the method may include spraying a precursor containing ruthenium (Ru) and molybdenum (Mo) toward the substrate S to form a precursor spraying step P of the metal thin film layer 110. pr , spray containing oxygen (O 2) The first processing gas is used to remove impurities contained in the metal film layer 110 in the first processing step P t1 , etching a portion of the metal thin film layer deposited on the upper surface of the substrate S by generating oxygen plasma while spraying the first processing gas; 電漿 -1 , and spraying containing hydrogen (H 2) The second processing gas is generated in the etching step P 電漿 -1Step P of reducing the metal oxide (solid) in the t2 . Here, because it contains hydrogen (H 2) The second processing gas is sprayed as in the above exemplary embodiment and another exemplary embodiment, so the step of reducing the metal oxide (solid) to metal is named "second processing step P t2 In addition, for convenience of explanation, the step P of etching a portion of the metal thin film layer 110 deposited on the upper surface of the substrate S by generating oxygen plasma while spraying the first processing gas is described below. 電漿 -1 Named as the first plasma treatment step P 電漿 -1 "(b) in Figure 5). Therefore, the method for forming an electrode according to yet another exemplary embodiment may include a precursor spraying step P pr , the first blowing step P pu1 , the first processing step P t1 , first plasma treatment step P 電漿 -1 , the second blowing step P pu2 , the second processing step P t2 And the third blowing step P pu3 . In addition, in a method for forming an electrode according to yet another exemplary embodiment, one process cycle CY may include a precursor spraying step P pr - First blowing step P pu1 - First processing step P t1 -First plasma treatment step P 電漿 -1 - Second blowing step P pu2 - Second processing step P t2 - The third blowing step P pu3 ", and the process cycle CY can be repeated multiple times and performed. Because the precursor spraying step P pr And the first blowing step P pu1 To the third blowing step P pu3 The precursor spraying step P of this exemplary embodiment and another exemplary embodiment pr And the first blowing step P pu1 To the third blowing step P pu3 are similar, so their description will be omitted. The first processing step P according to another exemplary embodiment described above t1 The method comprises a first processing gas spraying step and an oxygen plasma generating step. That is, as shown in FIG4 , according to another exemplary embodiment, the first processing step P t1 Oxygen plasma is continuously generated while the first process gas is sprayed. In other words, while the first process gas is sprayed, power for generating plasma is applied by applying radio frequency (RF) power to at least one of a susceptor on which the substrate S is placed and a spraying unit for spraying the first process gas into the chamber. Therefore, while the first process gas is sprayed, oxygen (O) plasma is generated within the chamber. However, according to yet another exemplary embodiment, the first processing step P t1 The step of spraying the first processing gas is included, but the step of generating plasma is not included. t1 The first plasma treatment step P is then performed 電漿 -1 The method includes the steps of spraying a first processing gas and generating plasma by using the first processing gas. In other words, before starting to spray the first processing gas (the first processing step (P t1 )) during the first set period after which plasma is not generated, and then after the first set time (first plasma treatment step (P 電漿 -1), oxygen plasma is generated simultaneously with the spraying of the first process gas. In other words, at the start of spraying the first process gas (first process step (P t1 )) during the first set period after the first plasma treatment step (P 電漿 -1 ), during a second set period starting from the time of ), power for generating plasma is applied while spraying the first process gas to generate oxygen plasma. The step of generating plasma while spraying the first process gas is defined as a first plasma processing step P in yet another exemplary embodiment. 電漿 -1 . Hereinafter, referring to FIG. 5 , a method according to yet another exemplary embodiment will be described in more detail. For example, when a precursor is sprayed onto the substrate S and then contains oxygen (O 2) When the first process gas is sprayed, the metal film layer 110 formed on the substrate S may be the same as the metal film layer 110 in FIG5 (a). That is, the thickness T of the metal film layer deposited on the upper surface of the substrate S is 1 may be greater than the thickness T of the metal thin film layer deposited on the inner wall surface forming the trench TR 2. T 3. In the first processing step P where the first processing gas is sprayed to remove impurities t1 After the termination, the first plasma treatment step P 電漿 -1 That is, a first plasma processing step P is performed by generating plasma using the first processing gas while spraying the first processing gas. 電漿 -1 To this end, radio frequency (RF) power is applied to the susceptor on which the substrate S is provided and to the substrate containing oxygen (O 2) The first process gas is sprayed into the chamber while at least one of the spraying parts is used to spray the gas into the chamber. Therefore, as shown in FIG5(b), oxygen plasma is generated inside the chamber. When oxygen plasma is generated inside the cavity, the metal and oxygen (O 2). In addition, this reaction will produce solid metal oxides and gaseous metal oxides. For example, when oxygen plasma is generated inside the cavity, ruthenium (Ru) and oxygen (O) contained in the metal film layer 110 will react. 2) will react. Therefore, a solid phase RuO 2 (solid) and gas-phase RuO 4 (gas) (see (b) in Figure 5). Among these, solid phase RuO 2 (solid) will remain in the metal film layer 110, and the gas phase RuO 4 (gas) is removed from the metal thin film layer 110 in the gas phase. That is, a portion of the metal thin film layer 110 is converted into, for example, RuO 4 gaseous metal oxides and are removed by etching reaction. Etching mainly occurs in the metal film layer 110 deposited on the upper surface of the substrate S. This is because when the oxygen plasma is generated on the upper side of the substrate S, the metal film layer 110 formed on the upper surface of the substrate S is closer to the oxygen plasma than the metal film layer 110 formed on the inner wall surface of the trench TR. Therefore, when the oxygen plasma is generated, the etching rate and etching thickness of the metal film layer 110 formed on the upper surface of the substrate are greater than the etching rate and etching thickness of the metal film layer 110 formed on the inner wall surface of the trench TR. Therefore, as shown in (c) of FIG. 5 , when the first plasma treatment step P for generating oxygen plasma is performed, 電漿 -1 When the thickness T of the metal thin film layer 110 formed on the inner wall surface of the trench TR is reduced, 2. T 3 and the thickness T of the metal thin film layer 110 formed on the upper surface of the substrate S 1. Second processing step P t2 In the first plasma treatment step P 電漿 -1 The process is then performed and is a process that will be generated in the first plasma treatment step P 電漿 -1 The second processing step P t2 Contains spray containing hydrogen (H 2) the second processing gas step. When spraying the second processing gas containing hydrogen (H 2) When the second processing gas is used, the metal oxide in the metal film layer reacts with hydrogen and is reduced to metal. For example, as generated in the first plasma treatment step P 電漿 -1 RuO 2 (solid) will react with hydrogen (H 2) reacts and is reduced to metallic ruthenium (Ru). In addition, the second processing step P t2 When the plasma is generated, the second processing step P t2 The method may include the steps of spraying a second process gas and generating plasma by using the second process gas. In this case, since the second process gas contains hydrogen (H 2), so it is generated in the second processing step P t2 The plasma in the reactor can be described as hydrogen plasma. Furthermore, hydrogen plasma can accelerate the reaction that reduces the metal oxide to metal. Therefore, the time required to reduce the metal oxide to metal can be shortened. As mentioned above, in the second processing step P t2 The first plasma treatment step P of producing metal is performed before 電漿 -1 Therefore, the first plasma treatment step P 電漿 -1 The second processing step P t2 The previous pre-processing step P 電漿 -1 ". [Example 4] FIG. 7 is a conceptual diagram for describing a method for forming an electrode according to yet another exemplary embodiment. In FIG7 , the term “ON” may refer to spraying a material for a process or generating plasma, and the term “OFF” may refer to stopping or terminating the spraying of the material or the generation of plasma. Yet another exemplary embodiment is similar to the above-mentioned yet another exemplary embodiment. However, in yet another exemplary embodiment, as shown in FIG. 7 , a first plasma treatment step P is performed. 電漿 -1 , and then the first processing step P t1 That is, according to yet another exemplary embodiment, the process cycle CY is composed of a "precursor spraying step P pr - First blowing step P pu1 -First plasma treatment step P 電漿 -1 - First processing step P t1 - Second blowing step P pu2 - Second processing step P t2 - The third blowing step P pu3 " in the order of ". When the third treatment step P is performed to form oxygen plasma t3 Then, oxygen (O 2) The first gas treatment step P t1 When the first processing step P t1 That is, compared to the time required to remove the ligand impurities in the first treatment step P t1 Then, a first plasma treatment step P is performed. 電漿 -1 In yet another exemplary embodiment, a first plasma treatment step P is performed. 電漿 -1 Then the first processing step P is performed t1 Yet another exemplary embodiment improves the rate of removal of ligand impurities. In the above, another exemplary embodiment and yet another exemplary embodiment are described as being used to form the metal thin film layer 110 on the substrate S having the trench TR. However, the present invention is not limited thereto, and any of the above-mentioned another exemplary embodiment and yet another exemplary embodiment can be applied to form the metal thin film layer 110 on a flat surface (i.e., without the trench TR) on the substrate S. Furthermore, the above description describes the formation of the metal thin film layer 110 containing at least one of ruthenium (Ru) and molybdenum (Mo) on the upper surface of the substrate S. However, this is not limiting. A predetermined thin film (hereinafter referred to as a base layer) may be formed on the upper surface of the substrate S, and the metal thin film layer 110 containing at least one of ruthenium (Ru) and molybdenum (Mo) may be formed on the upper portion of the base layer. In this case, for example, the base layer may be an active layer of a semiconductor device. When the bottom layer is indium gallium zinc oxide (IGZO), it is preferred that the bottom layer does not contain hydrogen (H 2) The gas is used as a second processing step P t2 This is because when IGZO is exposed to hydrogen (H 2), the electrical properties of the bottom layer may be degraded. Therefore, when the bottom layer is IGZO, it is better to include or not include hydrogen (H 2) of a gas (eg, argon (Ar)) is used to perform the second processing step P t2 . In addition, when the bottom layer is indium gallium zinc oxide (IGZO), in the second processing step P of spraying the second processing gas containing argon (Ar) t2 After termination, a sparging process containing hydrogen (H 2) post-processing step of the gas (hereinafter referred to as post-processing gas). In summary, when the bottom layer is indium gallium zinc oxide (IGZO), the process cycle CY can be "precursor spraying step P pr - First blowing step P pu1 - First processing step P t1 - Second blowing step P pu2 - Second processing step P t2 - Post-treatment step - Third blow-off step P pu3 Here, the second processing step P t2 The second treatment gas is sprayed with argon (Ar) gas, and the post-treatment step is sprayed with hydrogen (H 2) post-processing gas step. Because the second process gas containing argon (Ar) is sprayed and then containing hydrogen (H 2) is sprayed with post-processing gas (post-processing step), so the reaction of hydrogen (H 2) Caused by the damage of the bottom layer. In the above embodiment, the process cycle CY including the same steps is repeated multiple times. However, this is not limiting and multiple process cycles using different gases may be performed alternately. More specifically, the method for forming the electrode 100 may include a first process cycle CY1 and a second process cycle CY2. Here, the first process cycle CY1 may include a precursor spraying step P of spraying a precursor containing at least one of ruthenium (Ru) and molybdenum (Mo) toward the substrate S to form a first metal thin film layer. pr , spray containing oxygen (O 2) a first processing gas to remove impurities from the first metal film layer in a first processing step P t1 , a purge step P of spraying a purge gas after stopping spraying the first process gas pu2 , and a second processing step P of spraying a second processing gas containing argon (Ar) t2 In addition, the second process cycle CY2 may include a precursor spraying step P of spraying a precursor containing at least one of ruthenium (Ru) and molybdenum (Mo) onto the first metal film layer to form a second metal film layer. pr , spray containing oxygen (O 2) gas (hereinafter referred to as the third processing gas) to remove impurities from the second metal film layer in the third processing step P t3 , a purge step P of spraying a purge gas after stopping spraying the third process gas pu2 , and spraying containing hydrogen (H 2) The fourth process gas of the fourth process step P t4 . As mentioned above, the third process gas used in the second process cycle CY2 contains oxygen (O 2), and may be the same as the first processing gas used in the first process cycle CY1. In addition, the second process cycle CY2 can be performed in the purge step P pu2 and the fourth processing step P t4 The process further includes the step of spraying a gas including argon (Ar). As described above, according to the embodiment, an electrode can be formed in which ligand impurities generated by a precursor containing at least one of ruthenium (Ru) and molybdenum (Mo) are removed, thereby preparing the electrode 100 having low resistance. In addition, when the electrode 100 is formed on the substrate S having the trench TR, the step coverage can be improved by reducing the difference between the thickness of the metal film layer 110 formed on the inner wall of the trench TR and the thickness of the metal film layer 110 formed on the upper surface of the substrate S. According to an embodiment of the present invention, an electrode can be formed in which ligand impurities generated by a precursor containing at least one of ruthenium (Ru) and molybdenum (Mo) are removed, thereby producing an electrode with low resistance. Furthermore, when forming an electrode on a substrate having a groove, step coverage can be improved by reducing the difference between the thickness of a film formed on the inner wall of the groove and the thickness of a film formed on the upper surface of the substrate. 100: electrode 110: metal film layer CY: process cycle P pr ,P pu1 ,P pu2 ,P pu3 ,P t1 ,P t2 ,P 電漿 -1 :Step S: Substrate T 1,T 2,T 3: Thickness TR: Groove Exemplary embodiments can be understood in more detail from the following description and the accompanying drawings, in which: FIG1 is a diagram illustrating a state in which an electrode is formed on a substrate according to an exemplary embodiment; FIG2 is a conceptual diagram for describing a method for forming an electrode according to an exemplary embodiment; FIG3 is a process diagram conceptually illustrating a method for forming an electrode according to an exemplary embodiment; FIG4 is a conceptual diagram illustrating a method for forming a metal thin film layer on a substrate according to another exemplary embodiment; FIG5 is a process diagram conceptually illustrating a method for forming an electrode according to yet another exemplary embodiment; FIG6 is a conceptual diagram for describing a method for forming an electrode according to yet another exemplary embodiment; and FIG. 7 is a conceptual diagram for describing a method for forming an electrode according to yet another exemplary embodiment. CY: process cycle P pr ,P pu1 ,P pu2 ,P pu3 ,P t1 ,P t2 :step

Claims

1. A method for forming an electrode, comprising: a step of preparing a substrate; a step of spraying a precursor comprising ruthenium (Ru) onto the substrate to form a metal thin film layer; a first processing step of spraying a first processing gas comprising oxygen (O2) onto the substrate; a purging step of spraying a purging gas after stopping the spraying of the first processing gas; and a second processing step of spraying a second processing gas comprising at least one of hydrogen (H2), argon (Ar), and helium (He) onto the substrate to anneal the metal thin film layer, wherein the method further comprises a first plasma processing step of forming an oxygen (O) plasma on the substrate, wherein the first plasma processing step is performed between the first processing step and the purging step, or between the step of forming the metal thin film layer and the first processing step, wherein, When the first processing step is performed after the first plasma processing step, the first processing step is performed after the plasma generation is stopped.

2. The method for forming an electrode as described in claim 1, wherein the steps of forming the metal thin film layer, the first processing step, the first plasma processing step, the blow-off step, and the second processing step are repeated multiple times, or the steps of forming the metal thin film layer, the first plasma processing step, the first processing step, the blow-off step, and the second processing step are repeated multiple times.

3. The method for forming an electrode as described in claim 1, wherein the process temperature of the second processing step is higher than the process temperature of the first processing step.

4. The method for forming an electrode as described in claim 1, wherein the pressure of the second processing step is about 5 Torr to about 7 Torr.

5. The method for forming an electrode as described in claim 1, wherein: The substrate includes a trench recessed downward from one of its upper surfaces; and the first plasma processing step further includes the step of converting a portion of the metal thin film layer into a gaseous metal oxide and then etching the metal thin film layer.

6. The method for forming an electrode as described in claim 5, wherein: When one portion of the metal thin film layer is converted into the gaseous metal oxide in the first plasma treatment step, another portion of the metal thin film layer is converted into a solid metal oxide; the second treatment gas sprayed in the second treatment step contains hydrogen (H2); and the second treatment step of spraying the second treatment gas containing hydrogen (H2) causes the hydrogen (H2) contained in the second treatment gas to react with the solid metal oxide contained in the metal thin film layer, thereby reducing the solid metal oxide into a metal.

7. The method for forming an electrode as described in claim 6, wherein the second processing step includes a step of generating a hydrogen plasma by using the second processing gas containing hydrogen (H2).

8. A method for forming an electrode, comprising: a step of preparing a substrate for forming an indium gallium zinc oxide (IGZO) thin film layer on one surface thereof; a step of spraying a precursor comprising ruthenium (Ru) onto the IGZO thin film layer to form a metal thin film layer; a first processing step of spraying a first processing gas comprising oxygen (O2) onto the substrate to remove impurities contained in the metal thin film layer; a purging step of spraying a purging gas after stopping the spraying of the first processing gas; and a second processing step of spraying a second processing gas comprising argon (Ar) onto the substrate to anneal the metal thin film layer, wherein the method further comprises a first plasma processing step of forming an oxygen (O) plasma on the substrate, wherein the first plasma processing step is performed between the first processing step and the purging step, or between the step of forming the metal thin film layer and the first processing step, wherein... When the first processing step is performed after the first plasma processing step, the first processing step is performed after the plasma generation is stopped.

9. The method for forming an electrode as described in claim 8 further includes a post-processing step performed after the second processing step, wherein a post-processing gas containing hydrogen (H2) is sprayed onto the substrate.

10. A method for forming an electrode, comprising: a step of preparing a substrate; a first process cycle step including a step of forming a first metal thin film layer on the substrate; and a second process cycle step including a step of forming a second metal thin film layer on the first metal thin film layer, wherein: The first process cycle includes: a step of spraying a precursor containing ruthenium (Ru) onto the substrate to form the first metal thin film layer; a first processing step of spraying a first processing gas containing oxygen (O2) onto the substrate; a purging step of spraying a purging gas after stopping the spraying of the first processing gas; and a second processing step of spraying a second processing gas containing argon (Ar) onto the substrate. The second process cycle includes: a step of spraying a precursor containing ruthenium (Ru) onto the first metal thin film layer to form the second metal thin film layer; a third processing step of spraying a third processing gas containing oxygen (O2) onto the first metal thin film layer; a purging step of spraying a purging gas after stopping the spraying of the third processing gas; and a fourth processing gas containing hydrogen (H2) onto the first metal thin film layer. A fourth processing step on a thin film layer, wherein the first process cycle step and the second process cycle step further include a first plasma processing step for forming oxygen (O) plasma on the substrate, wherein the first plasma processing step of the first process cycle step is performed between the first processing step and the blow-off step, or between the step of forming the metal thin film layer and the first processing step, wherein when the first processing step is performed after the first plasma processing step, the first processing step is performed after the plasma generation is stopped, the first plasma processing step of the second process cycle step is performed between the third processing step and the blow-off step, or between the step of forming the second metal thin film layer and the third processing step, and when the third processing step is performed after the first plasma processing step, the third processing step is performed after the plasma generation is stopped.

11. The method for forming an electrode as described in claim 10, wherein the fourth processing step comprises a step of including a gas containing argon (Ar) before spraying the fourth processing gas.

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