KR20150100994A - Method for forming ruthenium containing thin film by atomic layer deposition - Google Patents

Abstract

According to an embodiment of the present invention, a method to form a ruthenium-containing thin film by atomic layer deposition comprises: a step of supplying a ruthenium-containing precursor to a substrate inside a chamber; a step of purging the ruthenium-containing precursor from the chamber; a step of supplying a reaction gas to the substrate; a step of purging the reaction gas from the chamber; and a step of thermally treating the deposited ruthenium thin film. The reaction gas is an ammonia gas.

Description

METHOD FOR FORMING RUTHENIUM CONTAINING THIN FILM BY ATOMIC LAYER DEPOSITION FIELD OF THE INVENTION [0001]

The present invention relates to a method for forming a ruthenium thin film by atomic layer deposition.

Ruthenium (Ru) is widely used in semiconductor devices due to its low resistance, relatively large work function and thermal and chemical stability. In particular, the ruthenium thin film is used as a seed layer in a wiring structure of a semiconductor device, or as an electrode such as a gate or a capacitor of a transistor. With the high integration and miniaturization of semiconductor devices, ruthenium thin films used in semiconductor devices are also required to have improved uniformity and applicability.

In addition, since the design rule is reduced as the electronic device such as a semiconductor device is reduced in size, a self-limiting mechanism of deposition is used to satisfy the low-temperature process, precise thickness control, thin film uniformity, thin film formation using Atomic Layer Deposition (ALD) following surface reaction mechanism is widely studied. The atomic layer deposition method is a method in which one or more reactants are sequentially introduced into a reaction chamber for forming a thin film, and the thin film is deposited by atomic layer by adsorption of each reactant. That is, the reactants are supplied in a pulsing manner and chemically deposited in the reaction chamber, and the remaining reactants physically bonded are removed in a purge manner.

One of the technical problems to be solved by the technical idea of the present invention is to provide a method for forming a ruthenium thin film by an atomic layer deposition method capable of forming a ruthenium thin film having improved coating properties and a low specific resistance.

A method for forming a ruthenium thin film by atomic layer deposition according to an embodiment of the present invention includes: supplying a ruthenium-containing precursor to a substrate in a chamber; Purging the ruthenium-containing precursor from the chamber; Supplying a reaction gas to the substrate; Purging the reaction gas from the chamber; And heat treating the deposited ruthenium thin film, wherein the reactive gas may be ammonia gas.

In some embodiments of the present invention, the pressure in the chamber may be greater than 50 Torr.

In some embodiments of the present invention, after the heat-treating step, the resistivity of the ruthenium thin film may be less than 50 mu OMEGA .cm.

In some embodiments of the present invention, the heat treatment step may be performed at a temperature of 300 DEG C or higher and under a hydrogen or ammonia atmosphere.

In some embodiments of the present invention, the temperature in the chamber may range from 230 ° C to 270 ° C.

In some embodiments of the present invention, the thickness of the ruthenium thin film may be saturated as the supply time of the ruthenium-containing precursor or the reaction gas increases in the temperature range.

In some embodiments of the present invention, the incubation period of the ruthenium thin film formation may be less than 10 deposition cycles, when it is referred to as a deposition cycle to perform the steps one by one in sequence.

In some embodiments of the present invention, the ruthenium-containing precursor is selected from the group consisting of dicarbonylbis (5-methyl-2,4-hexanedionato) Ru, bis (cyclopentadienyl) Ru (II), bis (ethylcyclopentadienyl) Ru , 6,6-tetramethyl-3,5-heptanedinonato (1,5-cyclooctadiene) Ru (III), (methylcyclopentadienyl) (Pyrrolyl) Ru (II).

A method for forming a ruthenium thin film by atomic layer deposition according to an embodiment of the present invention includes: supplying a ruthenium-containing precursor to a substrate in a chamber; Purging the ruthenium-containing precursor from the chamber; Supplying a reaction gas to the substrate; And purging the reaction gas from the chamber, wherein the ruthenium-containing precursor is dicarbonylbis (5-methyl-2,4-hexanedionato) ruthenium and the reaction gas is a reducing gas that reduces the ruthenium- have.

A method of forming a ruthenium thin film by an atomic layer deposition method capable of forming a ruthenium thin film having improved coating properties and a low specific resistance can be provided.

The various and advantageous advantages and effects of the present invention are not limited to the above description, and can be more easily understood in the course of describing a specific embodiment of the present invention.

1 is a flowchart illustrating a method of forming a ruthenium thin film according to an embodiment of the present invention.
2 is a gas injection flow diagram of an atomic layer deposition method for explaining a method of forming a ruthenium thin film according to an embodiment of the present invention.
FIG. 3 shows a structural formula of a ruthenium-containing precursor used in a method for forming a ruthenium thin film according to an embodiment of the present invention.
4A and 4B are graphs showing the thickness and specific resistance of the ruthenium thin film according to the supply time of the ruthenium-containing precursor in the ruthenium thin film forming method according to an embodiment of the present invention.
5A and 5B are graphs showing the thickness and specific resistance of the ruthenium thin film according to the supply time of the reactive gas in the method for forming a ruthenium thin film according to an embodiment of the present invention.
FIG. 6 is a graph showing deposition characteristics according to the number of deposition cycles in the method of forming a ruthenium thin film according to an embodiment of the present invention.
FIG. 7 is a graph showing an analysis result of a resistivity of a ruthenium thin film according to an embodiment of the present invention.
8 is a graph showing an analysis result of a crystal structure of a ruthenium thin film according to an embodiment of the present invention.
9 is an electron micrograph of a ruthenium thin film according to an embodiment of the present invention.
10 is a graph showing a result of composition analysis of a ruthenium thin film according to an embodiment of the present invention.
11A to 11C are electron micrographs illustrating the deposition characteristics of a ruthenium thin film according to an embodiment of the present invention.
12 is a schematic cross-sectional view showing a wiring structure of a semiconductor device including a ruthenium thin film according to an embodiment of the present invention.
13 is a schematic cross-sectional view illustrating a capacitor structure of a semiconductor device including a ruthenium thin film according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

The embodiments of the present invention may be modified into various other forms or various embodiments may be combined, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings may be exaggerated for clarity of description, and the elements denoted by the same reference numerals in the drawings are the same elements.

1 is a flowchart illustrating a method of forming a ruthenium thin film according to an embodiment of the present invention.

2 is a gas injection flow diagram of an atomic layer deposition method for explaining a method of forming a ruthenium thin film according to an embodiment of the present invention.

FIG. 3 shows a structural formula of a ruthenium-containing precursor used in a method for forming a ruthenium thin film according to an embodiment of the present invention.

Referring to FIGS. 1 and 2, a method for forming a ruthenium thin film according to an embodiment of the present invention includes the steps of supplying a ruthenium-containing precursor (S110), purging the ruthenium-containing precursor (S120) (S130), and purging the reaction gas (S140). The above steps may be performed on an object to be deposited, for example, a substrate, in a chamber of an atomic layer deposition apparatus. The steps may be performed sequentially one time to achieve one deposition cycle. The deposition cycle may be repeated a plurality of times depending on the thickness of the target ruthenium thin film. In addition, the method for forming a ruthenium thin film according to an embodiment of the present invention may further include a step (S150) of heat-treating the deposited ruthenium thin film after performing the deposition cycle.

Specifically, the ruthenium thin film forming method is constituted in the order of supply of the ruthenium-containing precursor as the source gas and supply of the reaction gas, and purge gas can be injected in the step of purging the source gas and the reactive gas after each supply step . In addition, an inert gas may be supplied to adjust the pressure in the chamber. In this case, the inert gas may use the same gas as the purge gas, but is not limited thereto. The gases may be supplied into the chamber and sprayed onto the substrate. The substrate may include a conductive material, a semiconductor material, or an insulating material on an upper surface thereof. The temperature in the chamber may be in the range of, for example, about 230 ° C to 270 ° C, and the pressure in the chamber may be in the range of 50 Torr or more, for example, about 80 Torr to 120 Torr. If the temperature is higher or lower than the above temperature, atomic layer deposition, that is, self-limiting growth may not occur. If the pressure is lower than the above-mentioned pressure, the reaction between the precursor and the reaction gas for forming the ruthenium thin film on the substrate may not be sufficient.

In this embodiment, the ruthenium-containing precursor and the supply time of the reaction gas and the supply time of the purge gas may be variously selected depending on the embodiment, and may be determined in consideration of the characteristics of the ruthenium thin film to be formed. This will be described in detail below with reference to Figs. 4A to 5B.

As shown in FIGS. 1 and 2, the step of supplying the ruthenium-containing precursor (S110) may be performed first. The step of supplying the ruthenium-containing precursor is a step of injecting a ruthenium-containing precursor as a source gas of ruthenium into the chamber.

Optionally, prior to the ruthenium-containing precursor supply, a precleaning process may be performed to remove etch residues or surface impurities that may be present on the substrate. The preliminary cleaning process may be a cleaning process using argon (Ar) sputtering or a cleaning process using a wet cleaning agent.

In this step, a ruthenium-containing precursor was prepared by dissolving dicarbonylbis (5-methyl-2,4-hexanedionato) ruthenium having the formula as shown in Figure 3 and the formula C ₁₆ H ₂₂ O ₆ Ru 5-methyl-2,4-hexanedionato) Ru) may be used. According to an embodiment, the ruthenium-containing precursor is selected from the group consisting of bis (cyclopentadienyl) Ru (II) [RuCp2], bis (ethylcyclopentadienyl) Ru , 5-heptanedinonato (1,5-cyclooctadiene) Ru (III) [Ru (thd) 2 (cod)], methylcyclopentadienyl (Pyrrolyl) Ru (II) [MeCpPyRu]. The precursor may be supplied into the chamber in a gaseous state, and if necessary, may be supplied into the chamber using an inert gas as a carrier gas.

Next, the step of purging the ruthenium-containing precursor (S120) may be performed. As the purge gas, argon (Ar), helium (He), nitrogen (N ₂ ) gas or the like can be used. By the purge gas, residual byproducts and unadsorbed ruthenium-containing precursors can be removed.

Next, a step of injecting the reaction gas (S130) may be performed. The reaction gas may be a reducing gas to assist in nucleation of the ruthenium-containing precursor adsorbed on the substrate and to reduce the ruthenium-containing precursor. In particular, the reaction gas may be ammonia (NH ₃ ).

According to the embodiment, since a reducing gas containing no oxygen is used as the reaction gas, the lower film may not be oxidized during the deposition process, and the lower film of the ruthenium thin film may not be oxidized after the formation. Thereby, it is possible to prevent an increase in the contact resistance between the ruthenium thin film and the underlying film due to the oxide formed at the interface with the lower film.

According to an embodiment, plasma may be applied to the inside of the chamber to enhance reactivity with the ruthenium-containing precursor when injecting the reaction gas. Plasma Enhanced ALD (PEALD) may be used, and ammonia (NH ₃ ) plasma, nitrogen (N ₂ ) and hydrogen (H ₂ ) mixed plasma, hydrogen (H ₂ ) .

Next, the step of purging the reaction gas (S140) may be performed. As the purge gas, argon (Ar), helium (He), nitrogen (N ₂ ) gas or the like can be used.

After the deposition cycle is performed at least once, a step (S150) of annealing the deposited ruthenium thin film may be further performed. The heat treatment, for example, be carried out in more than 300 ℃ temperature and hydrogen (H ₂₎ or ammonia (NH ₃₎ atmosphere.

The resistivity of the deposited ruthenium thin film before the heat treatment may have a relatively high value, for example, a resistivity value of 700 mu OMEGA .cm or more. Therefore, the resistivity can be reduced by improving the crystal quality through the heat treatment, and the resistivity of the ruthenium thin film after the heat treatment can be, for example, less than 50 μΩ · cm. This will be described in more detail below with reference to Figs. 7 to 10.

Hereinafter, the present invention will be described with reference to FIGS. 4A to 11C, focusing on the result of forming a ruthenium thin film according to an embodiment of the present invention.

4A and 4B are graphs showing the thickness and specific resistance of the ruthenium thin film according to the supply time of the ruthenium-containing precursor in the ruthenium thin film forming method according to an embodiment of the present invention.

In this embodiment, the temperature in the chamber is 250 占 폚, the pressure is 100 Torr, the purge gas supply time after the supply of the ruthenium-containing precursor is 30 seconds, the reaction gas supply time is 60 seconds, The ruthenium thin film was formed under the condition that the supply time was 60 seconds.

Referring to FIG. 4A, the thickness of the ruthenium thin film does not increase linearly but saturates as the supply time of the ruthenium-containing precursor, i.e., the pulsing time, increases. This self-limiting growth occurs when the ruthenium-containing precursor feed time is greater than about 45 seconds. However, the time for supplying the precursor, the reactive gas, and the purge gas may vary depending on the pump capacity, the chamber size, and the like according to the embodiment, and may be appropriately selected according to the specific embodiment.

Referring to FIG. 4B, the ruthenium thin film exhibits relatively high resistivity characteristics ranging from about 720 μΩ · cm to 800 μΩ · cm. In particular, when the supply time of the ruthenium-containing precursor is 20 seconds or less, the resistivity exhibits a large specific resistance. When the supply time of the ruthenium-containing precursor is 30 seconds or more, the stable resistivity characteristic exhibits a large variation.

5A and 5B are graphs showing the thickness and specific resistance of the ruthenium thin film according to the supply time of the reactive gas in the method for forming a ruthenium thin film according to an embodiment of the present invention.

In this embodiment, the temperature in the chamber is 250 DEG C, the pressure is 100 Torr, the supply time of the ruthenium-containing precursor is 45 seconds, the supply time of the purge gas after the supply of the ruthenium-containing precursor is 30 seconds, The ruthenium thin film was formed under the condition that the purge gas was supplied for 60 seconds.

Referring to FIG. 5A, the thickness of the ruthenium thin film does not increase linearly but saturates as the supply time of the reactive gas increases. This self-limiting growth occurs when the supply time of the reactive gas is at least about 60 seconds.

Referring to FIG. 5B, when the supply time of the reactive gas is 60 seconds or more, the resistivity exhibits a stable characteristic with a small variation and shows a resistivity of about 700 μΩ · cm to 760 μΩ · cm.

FIG. 6 is a graph showing deposition characteristics according to the number of deposition cycles in the method of forming a ruthenium thin film according to an embodiment of the present invention.

Referring to FIG. 6, the thickness variation of the ruthenium thin film with increasing deposition cycle is shown.

In this embodiment, the temperature in the chamber is 250 占 폚, the pressure is 100 Torr, the supply time of the ruthenium-containing precursor is 45 seconds, the supply time of the purge gas after the supply of the ruthenium-containing precursor is 30 seconds, Was 60 seconds, and the supply time of the purge gas after the supply of the reaction gas was 60 seconds. The supply time of the ruthenium-containing precursor and the reaction gas was selected in consideration of the results of FIGS. 4A to 5B. In the following figures, the results for a ruthenium thin film formed on a silicon oxide (SiO ₂ ) substrate using a ruthenium precursor of dicarbonylbis (5-methyl-2,4-hexanedionato) Ru under these conditions are shown.

As can be seen, the thickness of the ruthenium thin film shows a linear relationship with respect to the deposition cycle. The deposition rate is about 0.09 nm / cycle, and it can be seen that the latency period of the ruthenium thin film is smaller than five deposition cycles by the line extending from the data.

7 to 10, the present invention will be described with reference to the results of heat treatment for a ruthenium thin film according to an embodiment of the present invention.

FIG. 7 is a graph showing an analysis result of a resistivity of a ruthenium thin film according to an embodiment of the present invention.

Referring to FIG. 7, it can be seen that the resistivity of the ruthenium thin film subjected to the heat treatment at 300 ° C. and 400 ° C. is lower than 50 μΩ · cm, as compared with the ruthenium thin film (Ref.) Not subjected to the heat treatment.

8 is a graph showing an analysis result of a crystal structure of a ruthenium thin film according to an embodiment of the present invention.

Referring to FIG. 8, the crystal structure analysis result of the ruthenium thin film by X-ray diffraction (XRD) is shown according to the heat treatment temperature. On the graph, signals of (10-10), (10-12), (10-11), (11-20) and (10-13) planes of the ruthenium are shown, and ruthenium A signal corresponding to silicon (Si) of the substrate on which the thin film is formed is generated.

As shown in the figure, the ruthenium thin film subjected to the heat treatment at 300 ° C and 400 ° C clearly shows a signal corresponding to the crystal planes as compared with the ruthenium thin film (Ref.) Not subjected to the heat treatment, Is crystallized.

9 is an electron micrograph of a ruthenium thin film according to an embodiment of the present invention.

Referring to FIG. 9, the ruthenium thin film used for the analysis was subjected to a heat treatment step at 300 ° C. and analyzed by a transmission electron microscope (TEM).

It can be seen that the ruthenium thin film has poly-crystalline after annealing at 300 ° C.

10 is a graph showing a result of composition analysis of a ruthenium thin film according to an embodiment of the present invention.

Referring to FIG. 10, a composition analysis result is shown by a secondary ion mass spectrometer (SIMS) on a ruthenium thin film subjected to heat treatment at 300 ° C.

The ruthenium thin film contains a relatively small amount of oxygen (O) and carbon (C) elements and contains at least 95% of ruthenium (Ru) elements. Although not shown in the drawing, the content of the carbon (C) element was remarkably decreased when compared with the compositional analysis result of the ruthenium thin film before the heat treatment. When the ruthenium thin film is subjected to heat treatment, it is considered that the crystallization is promoted by removing the carbon (C) element incorporated during the deposition of the ruthenium thin film, thereby improving the resistivity characteristic.

7 to 10, when the heat treatment step is performed on the deposited ruthenium thin film, the resistivity of the ruthenium thin film is remarkably lowered. This is because the ruthenium thin film is crystallized by the heat treatment and the crystal quality is improved. can do. In addition, it can be seen that this effect appears when the heat treatment temperature is 300 ° C or higher.

11A to 11C are electron micrographs illustrating the deposition characteristics of a ruthenium thin film according to an embodiment of the present invention.

11A to 11C, the ruthenium thin film used in the analysis was deposited on a trench pattern under the conditions described above with reference to FIG. 6, and was formed by performing heat treatment at 300 DEG C, and a transmission electron microscope (TEM ). The trench pattern has an upper diameter of about 60 nm, a lower diameter of about 30 nm, and an aspect ratio of about 43: 1. 10A to 10C show the top, middle and bottom regions of the trench pattern, respectively.

As shown, it can be seen that the ruthenium thin film was uniform and conformally deposited also on the high aspect ratio pattern. This is because it is easy to control the thickness of the thin film by suppressing the gas phase reaction between the precursor and the reactant according to the atomic layer deposition method and using the self-limiting surface reaction mechanism on the surface of the substrate. Thus, the ruthenium thin film according to the present invention can be deposited uniformly and with excellent step coverage for trenches, contacts, or via patterns having a high aspect ratio due to miniaturization of semiconductor devices.

12 is a schematic cross-sectional view showing a wiring structure of a semiconductor device including a ruthenium thin film according to an embodiment of the present invention.

12, the semiconductor device may include a substrate 100, a first wiring film 110, an insulating film 120, a ruthenium thin film 130, and a second wiring film 140.

The substrate 100 may comprise a semiconductor material, such as a Group IV semiconductor, a Group III-V compound semiconductor, or a Group II-VI oxide semiconductor. The substrate 100 may be provided as a bulk wafer or an epitaxial layer. In addition, the substrate 100 may be a SOI (Silicon On Insulator) substrate. The substrate 100 may further include another region of a semiconductor element (not shown), for example, a transistor region.

The first and second wiring films 110 and 140 represent lower and upper wiring, respectively, and may include a conductive material. The first and second wiring films 110 and 140 may be formed of a material such as copper (Cu), aluminum (Al), nickel (Ni), silver (Ag), gold (Au), platinum At least one metal selected from the group consisting of lead (Pb), titanium (Ti), chrome (Cr), palladium (Pd), indium (In), zinc (Zn) Oxide. ≪ / RTI > The first and second wiring films 110 and 140 may be formed by electroplating, PVD or CVD. In particular, the second wiring layer 140 may include a via region adjacent to the first wiring layer 110, and may be formed by a dual damascene process.

The insulating layer 120 may include an insulating material such as a low- k material. The low dielectric material may have a dielectric constant of less than about 4. The low-k material may be, for example, silicon carbide (SiC), silicon oxide (SiO _2), fluorine-containing silicon oxide (SiOF) or fluorine-containing oxide. Or doped oxides such as HSQ (Hydrogen silesquioxane), FSG (Fluorinated Silicate Glass), MSQ (Methyl Silsesquioxane) and HOSP (Organo Siloxane Polymer, manufactured and sold by the United States AlliedSignal Inc.), SiLK (Trade names manufactured and sold by the US Dow Chemical Company), BCB (BenzoCycloButene), and FLARE (trade names manufactured and sold by AlliedSignal Inc., USA), or porous materials such as aerogels .

The ruthenium thin film 130 may be formed by a method of forming a ruthenium thin film according to an embodiment of the present invention. The ruthenium thin film 130 may be used as a seed layer and / or a diffusion preventing layer for forming the second wiring film 140. In one embodiment, when the ruthenium thin film 130 is used only as a seed layer, a separate diffusion preventing layer may be disposed under the ruthenium thin film 130. Particularly, when the second wiring film 140 is made of copper (Cu), the ruthenium thin film 130 can be advantageous in that solid solution formation with the second wiring film 140 is difficult and adhesion is excellent.

Since the ruthenium thin film 130 is formed by the ruthenium thin film forming method according to an embodiment of the present invention, the ruthenium thin film 130 can exhibit a high step coverage and a low resistivity even in a high aspect ratio pattern. In addition, according to this embodiment, atomic layer deposition can be performed using ammonia not containing oxygen as a reaction gas, so that the lower film, for example, the first wiring film 110 or the lower diffusion preventing layer is oxidized Can be prevented.

13 is a schematic cross-sectional view illustrating a capacitor structure of a semiconductor device including a ruthenium thin film according to an embodiment of the present invention.

13, the semiconductor device may include a substrate 200, a conductive film 210, an insulating film 220, and a capacitor 240. The capacitor 240 may include a lower electrode 242, a dielectric layer 244, and an upper electrode 246.

The substrate 200 may comprise a semiconductor material, such as a Group IV semiconductor, a Group III-V compound semiconductor, or a Group II-VI oxide semiconductor. The substrate 200 may have another region of a semiconductor element, for example, a transistor region, which is not shown. The conductive film 210 may be a conductive region disposed on the substrate 200 and may be a plug connecting the capacitor 240 to another region of the semiconductor device. The conductive film 210 may comprise a conductive material, for example, titanium nitride (TiN) or tungsten (W). The insulating layer 220 may include an insulating material and a hole H for forming the capacitor 240 may be formed.

The lower electrode 242 may be arranged to be connected to each other in the adjacent holes H and the upper electrode 246 may also be connected to each other by embedding the holes H. [ However, according to the embodiment, the capacitors 240 may be formed in only one hole H, or may be arranged so that they are not connected to each other between adjacent holes H. The lower electrode 242 and upper electrode 246 are, for example, doped polysilicon, titanium nitride (TiN), tungsten (W), tungsten nitride (WN), ruthenium (Ru), ruthenium oxide (RuO _2), Iridium (Ir), iridium oxide (IrO ₂ ), and platinum (Pt). In particular, at least one of the lower electrode 242 and the upper electrode 246 may be a ruthenium thin film formed according to an embodiment of the present invention. The ruthenium thin film according to an embodiment of the present invention can be deposited with high uniformity even when applied to a cylindrical capacitor or a cylindrical capacitor having a high aspect ratio. According to the present embodiment, atomic layer deposition can be performed using ammonia not containing oxygen as a reaction gas, thereby preventing the lower film, for example, the conductive film 210 or the lower diffusion preventing layer from being oxidized can do.

The dielectric layer 244 may include any of high- k materials such as, for example, ZrO ₂ , Al ₂ O ₃ , and Hf ₂ O ₃ . The dielectric layer 244 may be formed of a composite layer including two or more layers of the high dielectric constant material.

Although the ruthenium thin film is used in the wiring structure and the capacitor of the semiconductor device in the above embodiments, the use of the ruthenium thin film according to one embodiment of the present invention is not limited to this, There will be.

The present invention is not limited to the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

100, 200: substrate
110: first wiring film
120, 220: insulating film
130: ruthenium thin film
140: second wiring film
210: conductive film
240: capacitor
242: Lower electrode
244: Dielectric film
246: upper electrode

Claims (9)

Supplying a ruthenium-containing precursor to the substrate in the chamber;
Purging the ruthenium-containing precursor from the chamber;
Supplying a reaction gas to the substrate;
Purging the reaction gas from the chamber; And
Heat treating the deposited ruthenium thin film,
Wherein the reactive gas is an ammonia gas. The method for forming a ruthenium thin film according to claim 1, wherein the reactive gas is ammonia gas.
The method according to claim 1,
Wherein the pressure in the chamber is greater than 50 Torr.
The method according to claim 1,
Wherein the resistivity of the ruthenium thin film is less than 50 占 占 cm m after the heat treatment.
The method according to claim 1,
Wherein the heat treatment is performed at a temperature of 300 ° C or higher and in an atmosphere of hydrogen or ammonia.
The method according to claim 1,
Wherein the temperature in the chamber is in the range of 230 to 270 캜.
6. The method of claim 5,
Wherein the thickness of the ruthenium thin film is saturated as the supply time of the ruthenium-containing precursor or the reactive gas increases in the temperature range.
The method according to claim 1,
Wherein the incubation period of the ruthenium thin film formation is less than 10 deposition cycles when one of the steps is sequentially performed one deposition cycle.
The method according to claim 1,
The ruthenium-containing precursor may be selected from the group consisting of dicarbonylbis (5-methyl-2,4-hexanedionato) Ru, bis (cyclopentadienyl) Ru (II), bis (ethylcyclopentadienyl) Ru , 5-heptanedinonato (1,5-cyclooctadiene) Ru (III), (methylcyclopentadienyl) (Pyrrolyl) Ru (II).
Supplying a ruthenium-containing precursor to the substrate in the chamber;
Purging the ruthenium-containing precursor from the chamber;
Supplying a reaction gas to the substrate; And
And purging the reaction gas from the chamber,
Wherein the ruthenium-containing precursor is dicarbonylbis (5-methyl-2,4-hexanedionato) ruthenium, and the reaction gas is a reducing gas for reducing the ruthenium-containing precursor.

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