KR100255661B1 - Method for etching electrode layer of semiconductor device - Google Patents

Abstract

PURPOSE: A method for etching an electrode layer of a semiconductor device is provided to etch a metal layer by using a plasma. CONSTITUTION: A diffusion barrier(55a) is formed on a semiconductor substrate(51). A metal layer of a platinum group is formed on the diffusion barrier. A contact layer is formed on the metal layer of the platinum group. The semiconductor substrate(51) is loaded in an etching device of a constant temperature. One of a halogen gas, a chemical compound of the halogen gas, and a mixture of the halogen gas and the chemical compound flows in the etching device. A plasma is formed within the etching device. The metal layer of the platinum group is etched by inserting a material for forming a carbonyl compound into the etching device.

Description

Electrode layer etching method of semiconductor device

The present invention relates to an etching method of a semiconductor device, and more particularly to an electrode layer etching method of a platinum group metal.

As semiconductor devices have been highly integrated, capacitor structures using ferroelectric materials having dielectric constants, spontaneous polarizations, and residual polarizations of hundreds or more have been actively applied.

Conventionally, a dielectric film of a capacitor is formed by using a silicon oxide film (SiO ₂ ) having a dielectric constant of 4, which is difficult to apply to an ultra high density memory device (ULSI) due to low dielectric constant. Therefore, in order to increase capacity within a limited area, a method of decreasing the thickness of the dielectric film or increasing the effective area of the cell is used. This method complicates the process and makes the peripheral technology difficult, and also lowers the yield and productivity.

In contrast, when the dielectric film of the capacitor is formed using a material having a dielectric constant of 100 or more, that is, a ferroelectric material, the process of forming the capacitor may be simplified, and the process capability and device characteristics may be improved. The ferroelectric material includes barium titanate (BaTiO ₃ ), barium strontium titanate ((Ba, Sr) TiO ₃ ), barium lead titanate ((Ba, Pb) TiO ₃ ), lead titanate (PbTiO ₃ ), and lead Zirconate (PbZnO ₃ ), lead zirconium titanate (Pb (Zn, Ti) O ₃ ), strontium titanate (SrTiO ₃ ), and the like.

However, in order to form the dielectric film using the ferroelectric material as described above, development of peripheral technologies such as a method of patterning an electrode layer made of the electrode material and the stable electrode material when forming the ferroelectric material is required. Platinum (Pt) is used a lot as the electrode material. This is because platinum has a low reactivity with oxygen and a large work function to prevent a decrease in leakage current density and maintain a high dielectric constant of the ferroelectric. However, due to the chemical stability of platinum, there is a disadvantage in that etching using a chemical reaction is not easy.

In order to pattern the electrode layer, an etching method using a plasma is used. An etching method using the plasma includes a plasma etching method and a reactive ion etching (RIE) method. The plasma etching method uses a chemical reaction with a halogen gas, and is etched isotropically compared to the reactive ion etching method. The reactive ion etching (RIE) method uses a chemical reaction using a halogen gas and an inert gas. The etching method by a (physical) reaction is etched with anisotropy compared to the plasma etching method.

In other words, the reactive ion etching method combines a physical reaction by ion collision and a chemical reaction by plasma.

1 (a) to 1 (d) are cross-sectional views illustrating a method of etching an electrode layer of a semiconductor device according to the prior art, and particularly, a method of etching an electrode layer to form a storage electrode of a capacitor.

In the drawings, reference numeral 1 denotes a semiconductor substrate, 3 denotes an interlayer insulating layer, 5 denotes a diffusion barrier layer, 7 and 7a denote electrode layers, 9 and 9a denote adhesion layers, 11 denotes a mask layer, and 12 denotes residues. Indicates.

Referring to FIG. 1 (a), after the insulating material is deposited on the semiconductor substrate 1 to form the interlayer insulating layer 3, the diffusion barrier layer 5 and the electrode layer are formed on the interlayer insulating layer 3. (7) and the adhesion layer 9 are formed in order.

The electrode layer 7 is formed using platinum (Pt).

The diffusion barrier layer 5 is to prevent the platinum, which is a constituent material of the electrode layer 7, from being diffused and reacted under the polysilicon layer (not shown), and the adhesion layer 9 is a subsequent process. In order to facilitate the adhesion with the oxide film is deposited in.

The diffusion barrier layer 5 and the adhesion layer 9 are formed using any one of titanium (Ti) and titanium nitride (TiN).

Subsequently, an oxide film is deposited on the adhesion layer 9 and then patterned to form a mask layer 11.

Referring to FIG. 1B, the adhesion layer 9a and the electrode layer 7a are formed by plasma etching the adhesion layer 9 and the electrode layer 7 using the mask layer 11 as a mask.

At this time, since platinum, which is a constituent material of the electrode layer 7a, has a chemically stable property, that is, a low reactivity, and thus does not form a reaction product, an etching gas generally includes a highly reactive halogen gas such as chlorine (Cl ₂ ). use.

In the etching process, a plasma is formed to activate the etching gas, and oxygen is added to improve the etching selectivity with the adhesion layers above and below the electrode layer 7a.

As a result, the etched platinum is not volatilized and redeposited on the sidewall of the mask layer 11 / adhesive layer 9a to form a residue 12 which is a halogen compound in a solid state, and the nonvolatile residue 12 ) Interferes with etching and causes the sidewalls of the electrode layer 7a to have a predetermined slope rather than vertical.

Therefore, instead of the plasma etching process in which the chemical reaction is mainly used, a reactive ion etching method using a chemical reaction and an inert gas such as argon (Ar) to increase the sputtering effect at the same time is used. As a result of etching, that is, nonvolatile residue 12 is formed.

Referring to FIG. 1 (c), the mask layer 11 is removed using either hydrofluoric acid (HF) or a hydrofluoric acid mixture.

Referring to FIG. 1 (d), the residue 12 is removed.

As a result, a critical dimension loss appears between the electrode layers 7a, i.e., the portion where the barrier layer 5 is exposed.

Therefore, in the electrode layer etching method of the semiconductor device as described above, since platinum reacts with halogen gas, which is an etching gas, to form a nonvolatile residue, the etching rate is lowered and the pattern profile is lowered.

The technical problem to be achieved by the present invention is an electrode layer of a semiconductor device using a gas mixture for suppressing that the electrode layer is not formed in a desired pattern due to the non-volatile residue in the etching process for patterning the platinum group metal used as the electrode material of the ferroelectric film To provide an etching method.

1A to 1D are cross-sectional views illustrating an electrode layer etching method of a semiconductor device according to the prior art.

2 shows an etching apparatus of a semiconductor device.

3 is a graph showing the etching characteristics of the platinum electrode layer according to the process pressure.

4 is a graph showing etching characteristics of the platinum electrode layer according to the ratio of etching gas.

5 is a graph illustrating etching characteristics of the platinum electrode layer according to the etching gas ratio and the temperature of the lower electrode on which the semiconductor substrate is placed in the etching apparatus.

6 (a) to 6 (e) are cross-sectional views illustrating an electrode layer etching method of a semiconductor device according to the present invention.

In order to achieve the above object, the present invention forms an electrode layer by depositing a conductive material on a semiconductor substrate. The electrode layer is etched by using a gas mixture composed of any one of halogen gas, a compound of halogen gas, and a mixture thereof and a material forming a carbonyl compound as an etching gas and an etching method using plasma. .

In the gas mixture, a composition ratio of the material forming the carbonyl compound with any one of the halogen gas, the halogen gas compound, and a mixture thereof is 1: 0.01 to 1: 100.

Therefore, according to the present invention, by using an etching gas that can react with the constituent material of the electrode layer to form a volatile reaction product in the etching process of patterning the electrode layer, etching by chemical reaction is possible, and non-volatile residue on the sidewall of the electrode layer pattern Since this does not remain, an electrode layer having a desired pattern can be formed.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 shows an etching apparatus of a semiconductor device.

First, a semiconductor substrate having a 5000 nm thick oxide film, for example, SiO ₂ and a 3000 mm thick platinum electrode layer, is used as a first sample, and a semiconductor substrate having only 5000 nm thick oxide film as a second sample. 23 is mounted on the lower electrode 24 of the plasma etching apparatus.

Subsequently, the temperature control means 25 and the cooling means 26 and 27 are used to maintain the lower electrode 24 at a temperature of 0 to 500 ° C., and the mass flow rate control means 21 and the gas injection means 22 of the upper electrode. Reaction gas, such as chlorine (Cl ₂ ) and carbon monoxide (CO) is introduced in the ratio of 1: 0.01 to 1: 100. In addition, the pressure in the etching apparatus is controlled using a valve regulator of the pressure sensor 29 and the exhaust means 30, and the high frequency power is applied to the lower electrode 24 using the power supply means 28. Is applied.

10 ^-4 to 2 Torr pressure and 175 Watts of power are used to form a plasma in the etching apparatus to activate the reaction gas.

When the etching process is completed under the above process conditions, the power supply means 28 is shut off and the gas in the etching chamber is exhausted using the exhaust means 30 and the sample is taken out.

3 to 5 are graphs showing the etching rate of the platinum and the etching selectivity of the oxide layer (SiO ₂ ) with different process conditions in the etching apparatus of FIG. 2.

3 is a graph showing the etching characteristics of the platinum electrode layer according to the process pressure.

(a) shows the etching rate of the platinum electrode layer, and (b) shows the etching selectivity of the platinum electrode layer with respect to the oxide film.

In this case, when the process conditions are described, the etching gas flowing into the etching apparatus, that is, the ratio of chlorine (Cl ₂ ) and carbon monoxide (CO) is 1: 2.3 and the etching temperature is maintained at 250 ° C. while the pressure is 200 to 500 millitorr. (mTorr) range.

As a result, as the pressure increases, the etching rate (a) of the platinum electrode layer decreases and the etching selectivity ratio (b) of the platinum electrode layer to the oxide film increases. That is, as the pressure increases, the etching rate of the oxide film decreases faster than the etching rate of the platinum electrode layer.

4 is a graph showing the etching characteristics of the platinum electrode layer according to the ratio of the etching gas.

(a) shows the etching rate of the platinum electrode layer, and (b) shows the etching selectivity of the platinum electrode layer with respect to the oxide film.

In this case, the ratio of chlorine to carbon monoxide (Cl ₂ : CO, Cl ₂ / (Cl ₂ + CO)%) was maintained at 250 ° C. and 300 mTorr, and the ratio was 1: 0.43 (70%), 1: 1 (50%), 1: 1.5 (40%), 1: 2.3 (30%), 1: 4 (20%).

As a result, as the ratio of chlorine increases, the etching rate (a) of the platinum electrode layer decreases, whereas the etching selectivity (b) of the platinum electrode layer with respect to the oxide film increases.

Therefore, the ratio of chlorine and carbon monoxide is adjusted according to the conditions required in the process.

5 is a graph illustrating etching characteristics of the platinum electrode layer according to the etching gas ratio and the temperature of the lower electrode on which the semiconductor substrate is placed in the etching apparatus.

(a) and (b) is a case where the ratio of chlorine to carbon monoxide (Cl ₂ : CO) is 1: 1. First, (a) represents the etching rate of the platinum electrode layer, and (b) shows the etching of the platinum electrode layer with respect to the oxide film. Represents the selection ratio.

In addition, (c) and (d) is a case where the ratio of chlorine to carbon monoxide (Cl ₂ : CO) is 1: 2.3, (c) represents the etching rate of the platinum electrode layer, and (d) represents the etching of the platinum electrode layer with respect to the oxide film. Represents the selection ratio.

At this time, the temperature was changed to 50 to 350 ° C. while maintaining 300 mTorr pressure as the process conditions.

As a result, as shown in (a) and (c), as the temperature increases, the etching rate of the platinum electrode layer increases regardless of the proportion of chlorine.

However, in (b) and (d), the etching selectivity of the platinum electrode layer with respect to the oxide film is different as the temperature increases. That is, when the chlorine ratio is smaller than the carbon monoxide ratio, the etching selectivity ratio of the platinum electrode layer with respect to the oxide film is increased. When (d) increases while the ratio of chlorine is larger, the etching selectivity ratio (b) of the platinum electrode layer to the oxide film decreases.

Therefore, in the etching process of patterning the electrode layer, the electrode layer may be formed in a desired pattern by adjusting the ratio of temperature, pressure, and etching gas of the etching apparatus using the experimental results of FIGS. 2 to 5.

In this case, platinum group metals such as ruthenium (Ru), mosque (Os), iridium (Ir), rhodium (Rh), and palladium (Pd) may be used as the electrode layer, and chlorine (Cl ₂ ) may be used as an etching gas. ), In addition to fluorine (F ₂ ), bromine (Br ₂ ), iodine (I ₂ ) can be used any one of halogen gas, halogen compounds and mixtures thereof, in addition to carbon monoxide (CO) and carbon dioxide (CO ₂ ) and Carbonyl compounds containing a carbonyl group (> C = 0) can be used.

The halogen compounds include fluoride compounds (eg HF, CF ₄ , CHF ₃ ), chloride compounds (eg BCl ₃ , HCl), bromine compounds (eg HBr), and the like.

6 (a) to 6 (e) are cross-sectional views illustrating an electrode layer etching method of a semiconductor device according to the present invention, and particularly, a method of etching an electrode layer to form a storage electrode of a capacitor.

In the drawings, reference numeral 51 denotes a semiconductor substrate, 53 denotes an interlayer insulating layer, 55 and 55a denote diffusion barrier layers, 57 and 57a denote electrode layers, 59 and 59a denote adhesion layers, and 61 denotes mask layers, respectively.

Referring to FIG. 6A, a process of forming an interlayer insulating layer 53 by depositing an insulating material on a semiconductor substrate 51 and forming a diffusion barrier layer 55 on the interlayer insulating layer 53. To form an electrode layer 57 by depositing a conductive material on the diffusion barrier layer 55, and to form an adhesion layer 59 on the electrode layer 57.

The electrode layer 57 is formed using a material having a property capable of maintaining the dielectric constant of the ferroelectric material, for example, a platinum group metal such as platinum (Pt).

The platinum group metals include ruthenium (Ru), osmium (Os), iridium (Ir), rhodium (Rh), and palladium (Pd) in addition to the platinum.

The diffusion barrier layer 55 serves to prevent the constituent material of the electrode layer 57 from diffusing into a polysilicon layer (not shown) below, and the adhesion layer 59 is deposited in a subsequent process. It serves to facilitate the adhesion with the oxide film. The diffusion barrier layer 55 and the adhesion layer 59 may be formed of a single layer using any one of titanium (Ti) and titanium nitride (TiN), or may be formed of a multilayer formed by combining them.

Subsequently, an oxide film is deposited on the adhesion layer 59 and then patterned to form a mask layer 61. The mask layer 61 may be formed using any one of a photoresist film and a nitride film in addition to the oxide film.

Referring to FIG. 6 (b), the adhesion layer 59a is formed by dry etching the adhesion layer 59 using the mask layer 61 as an etching mask.

In this case, any one of a halogen gas, a halogen gas compound, and a mixture thereof may be used as the etching gas. In this embodiment, chlorine (Cl ₂ ) gas is used.

Referring to FIG. 6 (c), the electrode layer 57a is formed by etching the electrode layer 57 using an etching method using plasma.

As the etching gas, a substance that forms a carbonyl compound is added to any one of a highly reactive halogen gas, a halogen gas compound, and a mixture thereof, which is volatile because the substance forming the carbonyl compound is highly volatile. This is because the reaction product can be formed.

In other words, platinum, which is a constituent of the electrode layer 57, does not react with the halogen gas to form a volatile reaction product. Thus, by adding a material capable of forming a highly volatile carbonyl compound, the volatile reaction product is added to the halogen gas. Can be formed. Therefore, since the volatile reaction product is redeposited on the sidewall of the mask layer 61 / adhesive layer 59a during the etching or after the etching, it volatilizes without remaining as a residue, thereby forming the electrode layer 57a in a desired pattern.

The plasma etching processes are performed in an etching apparatus using any one of a reactive ion etching method and a plasma etching method.

The temperature of the etching apparatus is 0 ~ 500 ℃ and the pressure is 10 ^-4 ~ 2 Torr (Torr). As the etching gas, a material which forms a carbonyl compound with a material of halogen gas, a halogen gas compound, and a mixture thereof is used, based on the experimental results shown in the graphs of FIGS. Adjust process conditions.

In this case, the ratio of the etching gas, that is, the composition ratio of any one of the halogen gas, the halogen gas compound, and a mixture thereof and the carbonyl compound is 1: 0.01 to 1: 100. Chlorine (Cl ₂ ) is used as the halogen gas, and carbon monoxide (CO) is used as the material for forming the carbonyl compound, and a pressure of 300 mTorr and a high frequency power of 175 watts (w) are used. A plasma is activated to activate the etching gases.

Materials for forming the carbonyl compound include carbon dioxide (CO ₂ ) and carbonyl compounds in addition to the carbon monoxide (CO) as a highly volatile material. The carbonyl compound is an organic compound containing a carbonyl group (> C = 0).

In this case, in order to control the etching selectivity with the material layers above and below the electrode layer 57a and to enable anisotropic etching, the composition of the reaction gases may be changed or another gas may be further used. And hydrocarbons, fluorocarbons, oxygen, nitrogen, inert gases, and mixed gases thereof.

Next, a method of forming the electrode layer 57a will be described in connection with an etching apparatus. There are two methods.

In the first method, a step of loading the semiconductor substrate 51 in an etching apparatus at a predetermined temperature, forming a carbonyl compound and at least one material of a halogen gas and a mixture of halogen gas in the etching apparatus It proceeds to the step of introducing a substance and maintaining a constant pressure, and to form a plasma in the etching apparatus.

When the constituent material of the electrode layer 57 is platinum and the halogen gas in the etching gas is chlorine, bromine or iodine, the chemical reaction with carbon monoxide or carbon dioxide is as follows.

Pt + Cl ₂ + CO / CO ₂ ‥‥‥‥> Pt (CO) ₂ Cl ₂ ↑ (210 ℃, 1atm)

‥‥‥‥> Pt (CO) Cl ₂ ↑ (240 ℃, 1atm)

‥‥‥‥> Pt ₂ (CO) ₂ C1 ₄ ↑ (240 ℃, 1atm)

Pt + Br ₂ + CO / CO ₂ ‥‥‥‥> Pt (CO) ₂ Br ₂ ↑ (220 ℃, 1atm)

Pt + I ₂ + CO / CO ₂ ‥‥‥‥> Pt (CO) ₂ I ₂ ↑ (40 ℃, 1atm)

In a second method, a first process of loading the semiconductor substrate 51 into an etching apparatus having a plurality of etching chambers, and introducing a material of any one of a halogen gas, a halogen gas compound, and a mixture thereof into the etching apparatus. A second process of forming a plasma in the etching apparatus, a second process of injecting a material forming a carbonyl compound into the etching apparatus, and etching the electrode layer 57 on the semiconductor substrate 51. Proceed to Step 4.

In the second process, when the constituent material of the electrode layer 57 is platinum and the halogen gas in the etching gas is chlorine, bromine or iodine, the chemical reaction of the platinum and the halogen gas is as follows.

Pt + Cl ₂ ‥‥‥‥> PtCl _X

Pt + Br ₂ ‥‥‥‥> PtBr _X

Pt + I ₂ ‥‥‥‥> PtI _X

Therefore, as a second process output said mask layer (61) / adhesive layer (57a) (not shown), the residue consisting of a halogen compound in a solid state, such as PtCl _X, PtBr _X, PtI _X side wall formed as the lower portion Electrode layer 57 is not patterned vertically.

Therefore, the fourth step is to sublimate the residue from the solid state to the gas state to volatilize it from the sidewall of the mask layer 61 / adhesive layer 57a. The chemical reaction is as follows.

PtCl _x + CO / CO ₂ ‥‥‥‥> Pt (CO) ₂ Cl ₂ ↑ (210 ℃, 1atm)

‥‥‥‥> Pt (CO) Cl ₂ ↑ (240 ℃, 1atm)

‥‥‥‥> Pt ₂ (CO) ₂ Cl ₄ ↑ (240 ℃, 1atm)

PtBr _x + CO / CO ₂ ‥‥‥‥> Pt (CO) ₂ Br ₂ ↑ (220 ℃, 1atm)

PtI _X + CO / CO ₂ ‥‥‥‥> Pt (CO) ₂ I ₂ ↑ (40 ℃, 1atm)

That is, the halogen compounds in the solid state such as PtCl _X , PtBr _X , PtI _X are Pt (CO) ₂ Cl ₂ , Pt (CO) Cl ₂ , Pt ₂ (CO) ₂ C1 ₄ , Pt (CO) ₂ Br ₂ , Sublimates to gaseous state as Pt (CO) ₂ I ₂ .

Accordingly, the second and fourth processes may be repeated one or more times to form an electrode layer 57a having a more vertical sidewall.

In the third process, a plasma is formed by supplying a radio frequency power to the etching apparatus, and in the fourth process, a plasma is not supplied to the etching apparatus, that is, a plasma is not formed. Instead, the etching process is performed only by a chemical reaction with the substance forming the carbonyl compound.

In addition, the processes may be performed in the same etching chamber or in another etching chamber among the etching apparatuses, and when proceeding in another etching chamber, process conditions such as temperature, pressure, and high frequency power of each etching chamber may be different.

Referring to FIG. 6 (d), the mask layer 61 is removed.

At this time, since the constituent material of the mask layer 61 is an oxide film, the mask layer 61 is removed using either hydrofluoric acid (HF) or a hydrofluoric acid mixture.

Referring to FIG. 6 (e), the diffusion barrier layer 55 and the adhesion layer 59a corresponding to the electrode layers 57a may be formed by using any one of a halogen gas, a halogen gas compound, and a mixture thereof. Etch it.

In this case, chlorine is used as the halogen gas and the reaction is performed by any one of reactive ion etching (RIE) and plasma etching.

As a result, since the electrode layer 57a becomes a desired pattern, that is, a pattern in which the sidewalls thereof are vertical, a critical dimension loss does not appear between the electrode layers 57a, that is, a portion where the interlayer insulating layer 53 is exposed. .

The present invention is not limited to this, and it is apparent that many modifications are possible by those skilled in the art within the technical idea of the present invention.

As described above, the gas mixture according to the present invention and the electrode layer etching method of the semiconductor device using the same using an etching gas capable of reacting with the constituents of the electrode layer to form a volatile reaction product in the etching process of patterning the electrode layer. By using an etching method using plasma, etching by chemical reaction is possible, and non-volatile residues do not remain on the side of the electrode layer pattern. In addition, the etching selectivity of the electrode layer and the material layers above and below the electrode layer may be controlled by changing process conditions during etching.

Claims (31)

Forming a platinum group metal layer on the semiconductor substrate; And loading the semiconductor substrate into an etching apparatus at a constant temperature. Introducing a material of any one of halogen gas, a compound of halogen gas, and a mixture thereof into the etching apparatus and maintaining a constant pressure; Forming a plasma in the etching apparatus; And etching the platinum group metal layer by introducing a material forming a carbonyl compound into the etching apparatus. The method of claim 1, wherein the platinum group metal layer is platinum (Pt), ruthenium (Ru), osmium (Os), iridium (Ir), rhodium (Rh), or palladium (Pd). . The method of claim 1, wherein the etching step is performed at a temperature of 0 ~ 500 ℃. The electrode layer etching method of claim 1, wherein the halogen gas is a chlorine (Cl ₂ ) gas. The method of claim 1, wherein the material forming the carbonyl compound is at least one of carbon dioxide (CO ₂ ), carbon monoxide (CO), and a carbonyl compound. The method of claim 1, wherein in the etching step, the composition ratio of at least one material of the halogen gas, the halogen gas compound, and mixtures thereof: the material forming the carbonyl compound is 1: 0.01 to 1: 100. The electrode layer etching method of a semiconductor device. The method of claim 1, wherein the etching is performed at a pressure of 10 ⁻³ to 2 Torr. The method of claim 1, wherein the etching is performed by a reactive ton etching method. The method of claim 1, wherein the etching is performed by a plasma etching method. The method of claim 1, wherein the etching step further comprises any one or more of hydrocarbon-based, fluorocarbon-based, oxygen, nitrogen, inert gas, and a mixture thereof. The method of claim 1, wherein the step of maintaining the predetermined pressure to the platinum group metal layer etching step is repeated once after the platinum group metal layer etching step. The method of claim 1, wherein the plasma is formed by supplying a radio frequency power to the etching apparatus. The method of claim 1, wherein the platinum group metal layer etching step does not supply a radio frequency power to the etching apparatus. The method of claim 1, wherein maintaining the predetermined pressure and etching the platinum group metal layer are performed in different etching chambers among etching apparatuses having one or more etching chambers. The method of claim 1, wherein maintaining the predetermined pressure and etching the platinum group metal layer are performed in the same etching chamber among etching apparatuses having one or more etching chambers. Forming a diffusion barrier layer on the semiconductor substrate; Forming a platinum group metal layer on the diffusion barrier layer; Forming an adhesion layer on the platinum group metal layer; Forming a mask layer on the adhesion layer and then patterning the mask layer; Etching the adhesive layer using a material of any one of a halogen gas, a compound of halogen gas, and a mixture thereof; Loading the semiconductor substrate into an etching apparatus; Introducing a substance of any one of halogen gas, a compound of halogen gas, and a mixture thereof into the etching apparatus; Forming a plasma in the etching apparatus; Etching the platinum group metal layer on the semiconductor substrate into which the material forming the carbonyl compound is introduced into the etching apparatus; Removing the mask layer; And etching the diffusion barrier layer by using a material of any one of halogen gas, a compound of halogen gas, and a mixture thereof. The method of claim 16, wherein the platinum group metal layer is platinum (Pt), ruthenium (Ru), osmium (Os), iridium (Ir), rhodium (Rh), or palladium (Pd). . The method of claim 16, wherein the etching of the platinum group metal layer is performed at a temperature of 0 ° C. to 500 ° C. 18. The method of claim 16, wherein the etching of the platinum group metal layer is performed at a pressure of 30 ⁻³ to 2 Torr. The method of claim 16, wherein the material forming the carbonyl compound is at least one selected from carbon dioxide (CO ₂ ), carbon monoxide (CO), and carbonyl compounds. The method of claim 16, wherein in the etching of the platinum group metal layer, the composition ratio of any one of a halogen gas, a compound of halogen gas, and a mixture thereof: the material forming the carbonyl compound is 1: 0.01 to 1: 100. Electrode layer etching method of a semiconductor device, characterized in that. 17. The method of claim 16, wherein at least one of a hydrocarbon group, a fluorocarbon group, oxygen, nitrogen, an inert gas, and a mixed gas thereof is further used in etching the platinum group metal layer. . The method of claim 16, wherein the mask layer is formed using any one of a photoresist, an oxide film, and a nitride film. The method of claim 16, wherein the adhesion layer and the diffusion barrier layer are a single layer formed using any one of titanium (Ti) and titanium nitride (TiN). 17. The method of claim 16, wherein the adhesion layer and the diffusion barrier layer are multiple layers formed by combining titanium (Ti) and titanium nitride (TiN). The method of claim 16, wherein the etching steps are performed by any one of a reactive ion etching method and a plasma etching method. The method of claim 16, wherein after the etching of the platinum group metal layer, injecting any one material into the etching apparatus or etching the platinum group metal layer is repeated one or more times. . The method of claim 16, wherein the forming of the plasma comprises forming a plasma by supplying a radio frequency power to the etching apparatus. The method of claim 16, wherein etching the platinum group metal layer does not supply a radio frequency power to the etching apparatus. The semiconductor device of claim 16, wherein the inflow of any one material of the etching apparatus or the etching of the platinum group metal layer is performed in different etching chambers among etching apparatuses having one or more etching chambers. Electrode layer etching method. The semiconductor device of claim 16, wherein the inflow of any one material of the etching apparatus or the etching of the platinum group metal layer is performed in the same etching chamber among etching apparatuses having one or more etching chambers. Electrode layer etching method.

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