JP2000243921A - Semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the surface smoothness of a lower electrode and to suppress the increase in a leakage current by using an Ru metal that is orientated highly and whose half value width of an X-ray diffraction spectrum is set to a specific value or less for the lower electrode of a semiconductor device using a metal oxide as the dielectric film of a capacitor. SOLUTION: An Ru metal used as a lower electrode 6 of a metal oxide is orientated in the direction of (002) and further a peak half value width in the direction of (002) being measured by an X-ray diffraction spectrum is controlled to an extremely small value, namely 0.27 degrees or less, thus forming the Ru metal film 6 with improved surface smoothness. Also, when a metal oxide dielectric film 7 and further an upper electrode 8 are further formed on the lower electrode 6 with improved surface smoothness, they can have improved surface smoothness to reproduce the surface smoothness of the basic lower electrode 6, thus reducing the leakage current of a capacitor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device using a metal oxide as a dielectric film of a capacitor and a method of manufacturing the same, and more particularly, to a semiconductor device using Ru metal for a lower electrode and having good leakage current characteristics of the capacitor. And its manufacturing method.

[0002]

2. Description of the Related Art The degree of integration of semiconductor devices has been increasing year by year, and the cell area of capacitors has been reduced with the miniaturization of circuits.

[0003] In order to suppress the decrease in the capacitance of a capacitor due to such miniaturization, research has been actively conducted to secure a storage capacitance by applying a metal oxide to a dielectric film of the capacitor and increasing the dielectric constant. ing.

[0004] Particularly, in a memory application, the use of a ferroelectric film makes it possible to manufacture a non-volatile memory (hereinafter referred to as FeRAM) which does not lose information even when an external electrode is cut off. I am collecting.

When a metal oxide having such high dielectric properties or ferroelectric properties is applied to a capacitor dielectric film, it is of course important to select a high and ferroelectric material.
It can be said that the selection of the material of the electrode in contact with the dielectric and the manufacturing method thereof are also very important technical matters.

The reason for this is that, for example, since the high and ferroelectric materials represented by BST and PZT are composite metal oxides, the reduction of the capacitance film itself and the oxidation of the electrodes are caused, and as a result, the leakage current is reduced. This causes the deterioration of the capacitance characteristics such as an increase in the dielectric constant, a decrease in the dielectric constant, and a decrease in the remanent polarization.

In order to avoid such a phenomenon, a chemically stable platinum group metal is used as an electrode material. For example, platinum is less susceptible to redox reactions,
r, Ru, and Os show conductivity even when oxidized.

[0008] Among these platinum group metals, Ru is particularly preferred.
Has attracted much attention as a lower electrode of a capacitor using a metal oxide as a dielectric film because it can be finely processed by dry etching.

[0009]

However, the inventor has found that poor orientation and crystallinity of the Ru metal film as the lower electrode leads to an increase in the leakage current of the capacitor.

The poor orientation of Ru also affects the orientation of the metal oxide dielectric film, leading to a decrease in the dielectric constant, the adhesion between Ru and the base, or the effect of Ru on the metal oxide. It is also known that the adhesiveness is deteriorated and the adhesive is easily peeled off.

In view of the above problems, the present invention improves the surface smoothness of a lower electrode by using highly oriented Ru metal for a lower electrode of a semiconductor device using a metal oxide as a dielectric film of a capacitor. In particular, it is an object of the present invention to provide a semiconductor device in which an increase in leak current is suppressed and a method for manufacturing the same.

[0012]

According to the present invention, there is provided a semiconductor device using a metal oxide as a dielectric film of a capacitor, wherein a lower electrode of the capacitor is made of Ru metal oriented in a (002) direction; The present invention relates to a semiconductor device, characterized in that the half width of the X-ray diffraction spectrum of Ru metal is 0.27 degree or less.

Further, the present invention provides a semiconductor device using a metal oxide as a dielectric film of a capacitor, wherein the lower electrode of the capacitor is made of Ru metal, and the peak intensity in the (002) direction of the X-ray diffraction spectrum is: It is 170 times or more the peak intensity in the other direction, and the (00)
2) A semiconductor device having a half width in a direction of 0.27 degrees or less.

Further, the present invention relates to a method for manufacturing a semiconductor device using Ru metal as a lower electrode of a capacitor dielectric film made of a metal oxide, wherein the Ru metal is deposited at a DC power of 1.7 to 15 KW. The present invention relates to a method for manufacturing a semiconductor device, wherein a film is formed by a sputtering method in an Ar atmosphere at a temperature of 300 to 800 ° C. and an oxygen partial pressure of 20% or less.

Further, the present invention relates to a method for manufacturing a semiconductor device using Ru metal as a lower electrode of a capacitor dielectric film made of a metal oxide, wherein the Ru metal is deposited at a DC power of 1.7 to 15 KW. The present invention relates to a method for manufacturing a semiconductor device, wherein a film is formed by a sputtering method in an Ar atmosphere at a temperature of 300 to 800 ° C. and an oxygen partial pressure of 20% or less.

Further, the present invention provides a step of forming a MOS transistor on a semiconductor substrate, a first step of forming an interlayer insulating film on the transistor, and a step of forming an interlayer insulating film on the diffusion layer of the MOS transistor. A second step of opening a contact to be reached and embedding a conductive material, and forming a Ru metal layer with a DC power of 1.7 to 15 KW via a barrier layer on the entire surface of the interlayer insulating film having the conductive material. A third step of forming a film by a sputtering method in an Ar atmosphere at a temperature of 300 to 800 ° C. and an oxygen partial pressure of 20% or less;
a fourth step of patterning the u metal layer to form a lower electrode made of Ru metal on the contact plug in which the conductive material is embedded, and a fifth step of forming a metal oxide film on the lower electrode And a sixth step of forming a platinum group metal film on the metal oxide film.

Further, the present invention provides a step of forming a MOS transistor on a semiconductor substrate, a first step of forming an interlayer insulating film on the transistor, and a step of forming a diffusion layer of the MOS transistor on the interlayer insulating film. A second step of opening a contact to be reached and embedding a conductive material, and forming a Ru metal layer with a DC power of 1.7 to 15 KW via a barrier layer on the entire surface of the interlayer insulating film having the conductive material. A third step of forming a film by a sputtering method in an Ar atmosphere at a temperature of 300 to 800 ° C. and an oxygen partial pressure of 20% or less, a fourth step of forming a metal oxide film on the lower electrode, A semiconductor device comprising: a fifth step of forming a platinum group metal film on a metal oxide film; and a sixth step of patterning the Ru metal layer, the metal oxide film, and the platinum group metal film. How to make On.

When forming Ru metal in the above-described manufacturing method, it is preferable that the film be formed under the condition that oxygen is not supplied, that is, at an oxygen flow rate of zero.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a semiconductor device using a Ru metal as a lower electrode of a capacitor using a metal oxide as a dielectric film, and the use of the semiconductor device is not particularly limited. For example, DRAM, FeRAM
Such a semiconductor memory device may of course have a capacitor having the above structure in a partial region of a semiconductor element.

The metal oxide is not particularly limited as long as it is used as a material for a dielectric film of a capacitor. The oxide represented by the general formula ABO ₃ (wherein
A represents two or more kinds of divalent metal elements, lead and lanthanum, and B represents two or more kinds of tetravalent metal elements. ), For example, BST (general formula: Ba _1-x Sr _x TiO ₃ ) having high dielectric properties or ferroelectric properties, P
ZT (general formula: PbZr _x Ti _1-x O ₃ ), PLZT (general formula: Pb _1-x La _x Zr _1-y Ti _y O ₃ ), or Ta ₂
Preferred examples include O ₅ , SrBi ₂ Ta ₂ O ₉ , Bi ₄ Ti ₃ O _{12 and the} like.

Further, since the upper electrode does not have much influence on the characteristics such as the orientation of the metal oxide as compared with the lower electrode, it is necessary that the upper electrode is chemically stable especially in the state of being in contact with the metal oxide film. If so, the type is not particularly limited. A chemically stable platinum group metal of Ru, Rh, Pd, Os, Ir or Pt can be mentioned as a preferable example.

The present inventors have made intensive studies on the relationship between the orientation and crystallinity of the Ru metal used as the lower electrode of the metal oxide and the leakage current of the capacitor, and have reached the present invention.

Generally, in X-ray diffraction spectrum measurement, the intensity of the peak intensity of the spectrum indicates the degree of orientation of the sample, the half-width indicates the crystallinity of the sample, and the smaller the half-width, the smaller the half-width. It has good crystallinity.

By controlling the orientation of Ru metal in the (002) direction and controlling the half-width of the peak in the (002) direction measured by X-ray diffraction spectrum to a very small value of 0.27 degree or less, A Ru metal film having excellent surface smoothness can be formed.

The degree of orientation in the (002) direction is 100
%, It is preferable that the intensity in the (002) direction of the X-ray diffraction spectrum is 1% of the intensity in the other directions.
If it is 70 times or more, the effects of the present invention are exhibited.

When a metal oxide dielectric film and an upper electrode are further formed on the lower electrode having excellent surface smoothness as described above, they are used to reproduce the surface smoothness of the lower electrode as a base. And good surface smoothness.

[0027] The inventor has thus obtained the electrode /
It is considered that the leak current can be suppressed because the metal oxide interfaces are smooth with each other.

Here, when the half width is 0.27 degree or less, the leakage current value is 1 when ± 1 V is applied.
× 10 ⁻⁸ A / cm ² or less. With this leak current value, for example, the memory element can operate stably.

Conventionally, the formation of a Ru metal having such a narrow half width (that is, having good crystallinity) has not been realized, but the inventor of the present invention has made the formation of a Ru metal into a constant film. It has been found that a highly oriented and highly crystalline Ru metal film can be obtained by sputtering under the conditions. The details are described below.

First, an experiment for optimizing the film forming temperature by the sputtering method was performed. As shown in FIG. 8, the sputtering film forming apparatus includes a Ru target (300 m) disposed in a film forming chamber.
mφ), and a film is formed by sputtering on a substrate (for example, a 6-inch substrate). Further, the film forming chamber is connected to an exhaust mechanism and a mass flow controller. The film exhaust chamber is evacuated to a vacuum of 1 × 10 ^{−8 to} 9 × 10 ⁻⁷ torr by the exhaust mechanism. Can be introduced according to

FIG. 3 shows the results of evaluating the orientation and crystallinity of the Ru metal film when the sputtering film forming temperature of the Ru metal film was changed, using an X-ray diffraction spectrum. For the sample, a TiSi ₂ film and a TiN film were sequentially formed on a Si wafer, and a Ru metal film having a thickness of 120 nm was formed on the TiN film for evaluation. The sputtering conditions for the Ru metal film are as follows: after evacuation of the film formation chamber to 10 ⁻⁶ torr or less,
By injecting r gas, a film was formed under a condition of a total pressure of 10 mtorr and a DC power of 1.7 KW in an atmosphere of almost 100% Ar. Regarding the film formation temperature, room temperature, 20
Conditions of 0, 300, 400, and 500 ° C. were selected.

As shown in FIG. 3, room temperature (RT) and 2
When the film was formed at 00 ° C., only the Ru (101) peak was observed, but at 300 ° C. or higher, the peak almost disappeared.
It can be seen that the Ru metal film is very well oriented in the (002) direction. Table 1 shows the detailed readings of the peak intensity.
Shown in According to Table 1, at a film formation temperature of 300 ° C., (10
A minute peak was detected in the 1) direction. At 400 ° C., only peaks whose intensity was lower than the background were detected in the peaks other than the (002) direction.

[0033]

[Table 1] FIG. 4 shows the film formation temperature (horizontal axis) and Ru based on the results of FIG.
Intensity or half width (FWHM) of (002)
This is a plot of the relationship with. As shown in FIG. 4, it can be seen that as the film formation temperature increases, the strength indicating the orientation increases, the half-value width indicating the crystallinity decreases, and both of them move in a favorable direction. In particular, when the film is formed at a high temperature of 300 ° C. or higher, the half width becomes 0.27 degree or less. According to Table 1, especially, the above half width is
The peak intensity in the (002) direction at 0.27 degrees or less is 170 times or more the peak intensity in other directions (here, the (101) direction).

By further increasing the film forming temperature, better orientation and crystallinity can be obtained. However, if the temperature is too high, the transistor below the Ru metal film may be affected, and the temperature may be increased to 800 ° C. It is preferable to form a film below.

Next, an experiment of DC power optimization was performed. FIG. 5 shows the results of evaluating the orientation and crystallinity of the Ru metal film using the X-ray diffraction spectrum when the sputtering DC power of the Ru metal film was changed. The sample is S
A BPSG film was formed on the i-wafer, and a 100-nm-thick Ru metal film was further formed on the BPSG film for evaluation.
The sputtering conditions of the Ru metal film, the film forming chamber 10 ^-6-to
After evacuating to a vacuum of rr or less, Ar gas is injected to form a film having a total pressure of 10 mtorr under almost 100% Ar atmosphere.
r, film formation was performed at 500 ° C. Five conditions were selected for the DC power in the range of 0.7 to 5.7 KW.

As shown in FIG. 5, under these experimental conditions,
No peak other than Ru (002) was observed.

FIG. 6 is a plot of the relationship between the DC power (horizontal axis) and the intensity of Ru (002) based on the results of FIG. When the DC power is 0.7 KW, the intensity is a very weak value, but when the DC power is 1.7 KW or more, the intensity is high and the orientation is very good. On the other hand, if the DC power is too high, the film formation speed becomes too high, and it becomes difficult to control the film thickness.
The following is preferred. For example, if the DC power is 15
It is known that the film forming speed at the time of KW is 2 μm / min.

FIG. 7 is a plot of the relationship between the DC power (horizontal axis) and the half width (FWHM) of Ru (002) based on the results of FIG. Although a slight upward trend is observed with respect to DC power, any value has a half width of 0.
It is found to be between 22 and 0.24 degrees, indicating that very good crystallinity is exhibited.

In the above-described experiments for optimizing the film forming temperature and the DC power, in order to remove oxygen from the film forming chamber as much as possible, after evacuating to 10 ⁻⁶ torr or less, Ar
Gas was injected. In this way, low oxygen concentration
It is true that Ru metal has a constant conductivity even when oxidized, but when its resistance value (volume resistance) is compared, Ru: 7.
For 37 μΩcm, RuO ₂ : 30-40 μΩcm
This is because the resistance increases. As a result of the study by the present inventor, if the oxygen partial pressure is a low oxygen partial pressure that does not exceed 20% of the total pressure (oxygen and Ar), deterioration of surface smoothness and , Does not lead to a substantial increase in resistivity. Further, it is preferable that the film is formed under the condition that oxygen is not supplied optimally, that is, the oxygen flow rate is 0.

As described above, as the film forming conditions by the sputtering method, the DC power is 1.7 to 15 KW and the film forming temperature is 300.
If an Ar atmosphere having a temperature of up to 800 ° C. and an oxygen partial pressure of 20% or less is used, a Ru metal film oriented in the (002) direction with a half width of 0.27 degree can be formed.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an application example of a semiconductor device according to the present invention will be described using a DRAM and an FeRAM according to an embodiment.

Example 1 FIG. 1 is an enlarged sectional view of a thin film capacitor portion of a DRAM formed by the following method.

An SiO ₂ film 2 (600 nm) is formed as a thermally oxidized interlayer insulating film on a Si substrate 1 on which a MOS transistor has been formed in advance, and an opening reaching a diffusion layer (not shown) of the MOS transistor is formed in the SiO ₂ film. The opening was filled with a polycrystalline silicon plug 3 to secure electrical conduction. TiSi ₂ on this polycrystalline silicon plug
4 (30 nm), TiN5 (50 nm), and Ru metal 6 (500 nm) serving as a lower electrode were sequentially laminated.

In this embodiment, TiSi is used as the barrier layer.
_Although the structure in which the _two films and the TiN film are sequentially laminated is adopted, the barrier layer may be a single layer or a laminated structure. The barrier layer is made of a material that suppresses a reaction between the conductive material embedded in the contact plug, which is a Ru metal base, and the Ru metal. For example, contact plugs, silicon-based (S
i), Si and Ru as in this example.
What suppresses the reaction with is used.

The conditions for forming the Ru metal film at this time are as follows: after evacuation of the film formation chamber at 10 ⁻⁶ torr or less, Ar gas is injected, and a film formation temperature of 5% is obtained in an atmosphere of almost 100% Ar.
00 ° C, DC power 1.7KW, film formation pressure (total pressure) 10
mtorr.

The Ru / TiN / TiSi ₂ structure is patterned (width 0.4 μm) by photolithography.
To form a three-dimensional stacked electrode as shown in the figure by plasma etching.

On this wafer, a metal oxide dielectric film 7 (B
a, Sr) TiO ₃ (hereinafter referred to as BST film) was deposited to a thickness of 80 nm on a Ru metal film at a film formation temperature of 500 ° C. using an electron cyclotron resonance-CVD method (ECR-CVD method) (step coverage is about 40%). Therefore, BST of about 30 nm is stacked on the electrode side wall.) The raw materials for film formation include bis (dipivaloymethanate) barium (Ba (DP
M) ₂ ), bis (dipivaloymethanate) strontium (Sr
(DPM) ₂ ), titanium isopropoxide (Ti (o-
_{i-C 3 H 7) 4} ), it was used O _2. Film composition (Ba + Sr)
The / Ti ratio is 0.97 and the Ba / (Ba + Sr) ratio is 0.1.
The raw material supply amount was adjusted to be 5.

Thereafter, a Ru metal 8 of an upper electrode was deposited to a thickness of 50 nm by a sputtering method.
Is completed.

Using the completed device, the leakage current density of the thin film capacitor was measured.
It was found to be 5 × 10 ⁻⁹ A / cm ² , indicating good characteristics.

In this embodiment, the expansion formed on the semiconductor substrate is performed.
Polycrystalline silicon was used as a plug to connect to the layer
Is tungsten (W), tungsten silicide (W
Si _X), Titanium silicide (TiSi_X) Etc.
good.

In this embodiment, the BST film is used as the metal oxide dielectric film, but another metal oxide dielectric film such as Ta ₂ O ₅ or PZT may be used. In addition, R
Although u is used, other platinum group metals such as Ir and Pt can be used.

Embodiment 2 FIG. 2 is an enlarged cross-sectional view of a thin film capacitor portion of an FeRAM formed by the following method.

Thermally oxidized SiO ₂ film 2 (600 nm) on Si substrate 1 on which MOS transistors are formed in advance
An opening reaching the diffusion layer (not shown) of the MOS transistor was formed in the SiO ₂ film, and the opening was filled with a polycrystalline silicon plug 3 to secure electrical conduction. TiSi ₂ 4 (30 nm) on this polycrystalline silicon plug,
TiN5 (50 nm) and Ru metal 6 (100 nm) were sequentially laminated.

The conditions for forming the Ru metal film at this time are as follows. The film formation chamber is evacuated to 10 ⁻⁶ torr or less, and then an Ar gas is injected.
00 ° C, DC power 1.7KW, film formation pressure (total pressure) 10
mtorr.

On this wafer, a metal oxide dielectric film 7Pb is formed.
(Zr, Ti) O ₃ (hereinafter referred to as a PZT film) was deposited to a thickness of 200 nm on the Ru metal film by a sputtering method. Thereafter, an upper electrode Ru metal 8 is deposited to a thickness of 50 nm and further patterned by photolithography to complete the FeRAM structure shown in FIG. 2 using the capacitor of the present invention. In this embodiment, polycrystalline silicon is used as a plug connected to the diffusion layer formed in the semiconductor substrate. However, another material similar to that of the first embodiment can be used.

In this embodiment, a PZT film was used as the metal oxide dielectric film, but SrBi ₂ Ta ₂ O ₉ and Bi ₄ T
Other metal oxide dielectric films such as i ₃ O ₁₂ may be used.
Although Ru was used for the upper electrode, other platinum group metals such as Ir and Pt can be used.

Using this completed device, the leakage current density of the thin film capacitor was measured.
It was found to be 5 × 10 ⁻⁹ A / cm ² , indicating good characteristics.

[0058]

The semiconductor device using the metal oxide of the present invention as a dielectric film of a capacitor has the following effects.

First, especially when the lower electrode of the capacitor is R
Since it is u metal, processing is very easy.

Second, since the Ru metal film is highly oriented in the (002) direction and has a very narrow half-value width of 0.27 degree, the crystallinity is good. The current can be reduced. Further, the metal oxide film formed on such a highly oriented and highly crystalline lower electrode has high dielectric properties and thus has good dielectric properties.

Third, it has been impossible to form such a Ru metal film having high orientation and crystallinity conventionally.
It became possible by controlling the power and the film formation temperature.

[Brief description of the drawings]

FIG. 1 is an enlarged cross-sectional view of a thin film capacitor portion of a DRAM according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a thin film capacitor portion of the FeRAM according to one embodiment of the present invention.

FIG. 3 shows an X-ray diffraction spectrum of a Ru metal film when a sputtering film forming temperature of the Ru metal film is changed.

FIG. 4 is a graph showing the relationship between film formation temperature (horizontal axis) and Ru based on the results of FIG.
Intensity or half width (FWHM) of (002)
This is a plot of the relationship with.

FIG. 5 shows an X-ray diffraction spectrum of the Ru metal film when the sputtering DC power of the Ru metal film is changed.

FIG. 6 is a graph showing the DC power (horizontal axis) based on the results shown in FIG.
7 is a plot of the relationship between Ru (002) intensity (Intensity).

FIG. 7 is a graph showing the relationship between DC power (horizontal axis) and R based on the results of FIG.
It is a plot of the relationship between u (002) and the half width (FWHM).

FIG. 8 is a schematic view of a film forming apparatus used in the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Si substrate 2 interlayer insulating film 3 polycrystalline silicon plug 4 TiSi ₂ 5 TiN 6 lower electrode (Ru metal) 7 metal oxide dielectric film 8 upper electrode (Ru metal)

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[Procedure amendment]

[Submission date] March 2, 1999 (1999.3.2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 3

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 9

[Correction method] Change

[Correction contents]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

[0004] In the particular memory applications, strong by using the dielectric film, much attention because it can be produced in an external voltage nonvolatile memory without loss of information even blocked (hereinafter FeRAM) Are gathering.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction contents]

The metal oxide is not particularly limited as long as it is used as a material for a dielectric film of a capacitor. The oxide represented by the general formula ABO ₃ (wherein
A is a divalent metal element, represents one or more elements of the lead and lanthanum, B represents one or more elements of the tetravalent metal elements. ), For example, BST (general formula: Ba _1-x Sr _x TiO ₃ ) having high dielectric properties or ferroelectric properties, P
ZT (general formula: PbZr _x Ti _1-x O ₃ ), PLZT (general formula: Pb _1-x La _x Zr _1-y Ti _y O ₃ ), or Ta ₂
Preferred examples include O ₅ , SrBi ₂ Ta ₂ O ₉ , Bi ₄ Ti ₃ O _{12 and the} like.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) H01L 21/8247 29/788 29/792

Claims (10)

[Claims] In a semiconductor device using a metal oxide as a dielectric film of a capacitor, a lower electrode of the capacitor is made of Ru metal oriented in a (002) direction, and an X-ray diffraction spectrum of the Ru metal is obtained. When the half width is 0.
A semiconductor device having a temperature of 27 degrees or less. 2. A semiconductor device using a metal oxide as a dielectric film of a capacitor, wherein the lower electrode of the capacitor is made of Ru metal and has a (00
2) A semiconductor device wherein the peak intensity in the direction is 170 times or more the peak intensity in the other directions, and the half-width in the (002) direction is 0.27 degrees or less. 3. The method according to claim 1, wherein the metal oxide is an oxide represented by the general formula ABO ₃ , Ta ₂ O ₅ , SrBi ₂ Ta ₂ O ₉ , or Bi ₄ Ti ₃ O _12. 3. The semiconductor device according to 1 or 2. (In the general formula, A is a divalent metal element,
Represents two or more elements of lead and lanthanum, B is 4
It represents two or more kinds of valence metal elements. ) 4. The semiconductor device according to claim 1, wherein the metal forming the upper electrode facing the lower electrode via the metal oxide is a platinum group metal. 5. A method of manufacturing a semiconductor device using a Ru metal as a lower electrode of a capacitor dielectric film made of a metal oxide, wherein the Ru metal has a DC power of 1.7 to 15.
A method for manufacturing a semiconductor device, comprising: forming a film by a sputtering method in an Ar atmosphere having a KW of 300 to 800 ° C. and an oxygen partial pressure of 20% or less. 6. A step of forming a MOS transistor on a semiconductor substrate, a first step of forming an interlayer insulating film on the transistor, and contacting the interlayer insulating film with a contact reaching a diffusion layer of the MOS transistor. A second step of opening and embedding a conductive material, and forming a Ru metal layer on the entire surface of the interlayer insulating film having the conductive material via a barrier layer by applying a DC power of 1.7 to 15 KW and forming a film at a temperature of 300 to 150 KW. 8
A third step of forming a film by a sputtering method in an Ar atmosphere at 00 ° C. and an oxygen partial pressure of 20% or less; and forming a Ru metal layer on a contact plug in which the conductive material is embedded by patterning the Ru metal layer. A fourth step of forming a lower electrode, a fifth step of forming a metal oxide film on the lower electrode, and a sixth step of forming a platinum group metal film on the metal oxide film And a method for manufacturing a semiconductor device comprising: 7. A step of forming a MOS transistor on a semiconductor substrate, a first step of forming an interlayer insulating film on the transistor, and contacting the interlayer insulating film with a contact reaching a diffusion layer of the MOS transistor. A second step of opening and embedding a conductive material, and forming a Ru metal layer on the entire surface of the interlayer insulating film having the conductive material via a barrier layer by applying a DC power of 1.7 to 15 KW and forming a film at a temperature of 300 to 150 KW. 8
A third step of forming a film by a sputtering method in an Ar atmosphere at 00 ° C. and an oxygen partial pressure of 20% or less;
A fourth step of forming a metal oxide film, a fifth step of forming a platinum group metal film on the metal oxide film,
a sixth step of patterning the u metal layer, the metal oxide film, and the platinum group metal film. 8. The method of manufacturing a semiconductor device according to claim 5, wherein an oxygen flow rate during the formation of the Ru metal is zero. 9. The method according to claim 1, wherein the metal oxide is an oxide represented by the general formula ABO ₃ , Ta ₂ O ₅ , SrBi ₂ Ta ₂ O ₉ , or Bi ₄ Ti ₃ O _12. 9. The method for manufacturing a semiconductor device according to any one of 5 to 8. (In the general formula,
A represents two or more kinds of divalent metal elements, lead and lanthanum, and B represents two or more kinds of tetravalent metal elements. ) 10. The semiconductor device according to claim 5, wherein the metal forming the upper electrode facing the lower electrode via the metal oxide is a platinum group metal. Production method.