JPH11256318A - Conductive thin film and its formation as well as semiconductor device and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently form a conductive thin film having a uniform and sufficient nucleus density. SOLUTION: Ion species of a metal are formed by acting rare earth excitation species or/and electrons on gas contg. a metal. The metal ions are deposited on a substrate and with these ions as growth nuclei, the conductive thin film is formed by CVD, PVC, electrolytic plating, etc. More particularly this method is effective as a method of forming the conductive thin film on a semiconductor substrate having connection holes, in which a copper thin film is formed by using β-ketonato copper as a gaseous raw material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a conductive thin film and a method for forming the same, and a semiconductor device having the conductive thin film and a method for manufacturing the same.

[0002]

2. Description of the Related Art In general, aluminum (Al) is widely used as a wiring material for VLSI devices.
Copper (Cu) has attracted attention as a next-generation wiring material replacing aluminum.

[0003] Copper has a lower specific resistance than aluminum (specifically, the specific resistance of Cu is 1.72 μΩ · cm while the specific resistance of Al is 2.7 μΩ · cm). It has the property of being resistant to migration, stress migration, and the like.

[0004] As a technique for forming a copper thin film, an electrolytic plating technique is the closest to practical use, and some are expected to be put to practical use.

[0005] This electroplating technique requires a seed layer (Cu growth nucleus) for growing (depositing) copper, and a copper thin film formed by sputtering is currently used as the seed layer.

However, in the case of filling a fine diameter connection hole (for example, a contact hole or a via hole) having a high aspect ratio, a sufficient step coverage (wraparound ratio) cannot be obtained with a copper thin film formed by a sputtering method. Forming a copper seed layer by CVD (chemical vapor deposition),
Alternatively, it is necessary to fill all the connection holes having a small diameter by the CVD method.

[0007]

In a copper film forming technique by the CVD method (hereinafter, sometimes referred to as a CuCVD film forming technique), for example, Cu-β-ketonato copper (I) is used.
(hfac) (tmvs) (copper hexafluoroacetylacetonate tr
imethylvinylsilane: The structural formula is shown in FIG. 13 and the same applies hereinafter) as a copper-containing source gas, and the film is formed under heating at about 200 ° C.

In this CuCVD film forming technique, as shown in the following reaction formulas (A) and (B), and further, as shown in FIG. 13, copper is deposited by a thermal decomposition reaction of a raw material gas. Cu (hfac) (tmvs) → Cu (hfac) + tmvs ... (A) 2 Cu (hfac) → Cu + Cu (hfac) ₂ ... (B) [However, in the above reaction formulas A and B and FIG. 13, hfac
Means hexafluoroacetylacetonate, and tmvs means trimethylvinylsilane. ]

However, in this reaction, as can be seen from the above-mentioned reaction formulas (A) and (B), only about half of the copper atoms contained in the raw material gas can be used (precipitated). Is exhausted as Cu (hfac) ₂ , resulting in poor reaction efficiency. Further, the obtained copper thin film may contain a large amount of impurities (particularly carbon-based impurities), and it is difficult to say that the density of copper (nucleus generation density) is sufficient. Furthermore, the thermal decomposition reaction (precipitation reaction) of copper strongly depends on the surface state of the substrate serving as a base, and it is necessary to preliminarily set the state of the base substrate so that the source gas can be easily adsorbed. That is, since the thermal decomposition reaction (precipitation reaction) of copper is promoted by the transfer of electrons between the source gas and the underlying substrate, the oxidation and the like are suppressed so that an insulator is not formed on the surface of the underlying substrate, and In addition, it is necessary to maintain electrical conductivity as a base substrate.

Therefore, it is necessary to improve the copper deposition rate.
In addition, for the purpose of improving the nucleation density, it has been attempted to add H (hfac) (hexafluoroacetylacetone: the same applies hereinafter) during the above-mentioned CuCVD film formation.

According to this method, the hydrogen atom in H (hfac) reacts with the reaction formula (A) as shown in the following reaction formula (C).
Cu (hfac) generated in the reaction can be reduced to improve the reaction efficiency of the raw material gas. Cu (hfac) + H → Cu + H (hfac)… (C)

However, even in the method of adding H (hfac), the reaction efficiency is lower than in the case of adding a hydrogen atom itself.

Therefore, in order to directly supply hydrogen atoms to the reaction system, a mixed gas containing hydrogen gas is introduced into a plasma atmosphere.
It is known to form a copper film by a plasma CVD method in which Cu (hfac) (tmvs) is introduced and copper deposition efficiency is improved.

However, this method is governed by the state of incidence of the plasma-excited species into the connection holes and the like, and therefore has a lower step coverage than the above-mentioned method utilizing the thermal decomposition reaction of the raw material gas containing copper. In particular, when used to fill a connection hole or the like having a high aspect ratio, there remains a problem that a void is formed therein. In other words, as described above, the thermal decomposition reaction is a reaction by the raw material gas that has reached the surface of the underlying substrate, whereas the plasma CV
In D, charged particles such as ionic species and electrons in the plasma atmosphere govern film formation. Therefore, the plasma CV
In D, an electric field is inevitably formed between the underlying substrate and the plasma, and the electric field accelerates the charged particles in a direction perpendicular to the substrate surface. Is not isotropic and, for example, it is difficult to form a film on the side wall of the fine hole.

When the copper thin film formed by the above-mentioned CuCVD film forming technique is applied as a seed layer in the electrolytic plating technique, it is necessary to form a copper thin film of about 20 to 50 nm as a Cu growth nucleus. However, as mentioned above,
The growth of the copper thin film by the CuCVD film forming technique based on the thermal decomposition method strongly depends on the nucleation state at the initial stage of film formation, and a high nucleus density has not been obtained at present. For this reason, the film thickness 20 to
At present, it is still difficult to deposit a copper thin film having a uniform and sufficient nuclear density of about 50 nm on, for example, a semiconductor substrate.

The present invention has been made in view of the above-described conventional circumstances, and has as its object to form a conductive thin film having a uniform and sufficient nucleus density and to efficiently form such a conductive thin film. To provide a conductive thin film forming method.

Still another object of the present invention is to provide a semiconductor device conforming to the conductive thin film and the method for forming the same, and a method for manufacturing the same.

[0018]

That is, the present invention provides a process for generating ions of a metal by reacting a rare gas excited species and / or an electron with a gas containing the metal, and depositing the metal ions on a substrate. And a method for forming a conductive thin film (hereinafter referred to as a method for forming a conductive thin film of the present invention).

The present invention also relates to a conductive thin film (hereinafter referred to as a conductive thin film of the present invention) having a laminated structure composed of a growth nucleus layer composed of metal ions deposited on a substrate and a metal layer deposited on the growth nucleus. (Referred to as a conductive thin film).

The growth nucleus layer and the metal layer have different ratios of carbon-based impurities and the like in each layer, and also have different chemical structures. The layer and the metal layer are clearly observed (the same applies to the following semiconductor device of the present invention).

Further, according to the present invention, there is provided a method for generating ions of a metal by causing a rare gas excited species and / or electrons to act on a gas containing a metal, and depositing the metal ions on a semiconductor substrate. Forming a conductive thin film on a substrate,
A method of manufacturing a semiconductor device (hereinafter, referred to as a method of manufacturing a semiconductor device of the present invention) is provided.

The present invention further provides a conductive thin film having a laminated structure comprising a growth nucleus layer made of metal ions deposited on a semiconductor substrate and a metal layer deposited on this growth nucleus layer. A semiconductor device (hereinafter, referred to as a semiconductor device of the present invention) formed above is provided.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the action of the source gas and the rare gas excited species and / or the electrons is as follows:
It is considered to be expressed by an equation as shown in FIG.

The equation shown in FIG. 1 uses Cu (hfac) (tmvs), which is β-ketonato copper (I), as a raw material gas.
And, using argon as the rare gas, Cu (hfac) (t
mvs) by reacting an argon-excited species with an electron to generate ions of the metal.

First, as shown in FIG. 1 (1) and the following reaction formula (1), Cu (hfac) (tmv
s) The molecules collide with, for example, electrons (e) existing in the plasma atmosphere, and Cu (hfac) (tmvs) molecules are dissociated to generate Cu (hfac) molecules, tmvs molecules, and electrons. Cu (hfac) (tmvs) + e → Cu (hfac) + tmvs + e… (1)

Next, FIG. 1 (2) and the following reaction formula (2)
As shown in the figure, the Cu (hfac) (tmvs) molecule generated by the dissociation of the Cu (hfac) molecule
c) Copper ions (Cu ⁺ ) dissociate from the molecule. Cu (hfac) + e → Cu ⁺ + hfac + 2e ... (2)

Simultaneously with this reaction, as shown in FIG. 1 (3) and the following reaction formula (3), Cu (hfac)
(Tmvs) Molecule collides with argon excited species (Ar ^* ) excited in a plasma atmosphere, for example, and Cu (hfac) (tm
vs) Cu (hfac) molecule, tmvs molecule and argon excited species are generated by the dissociation of the molecule. Cu (hfac) (tmvs) + Ar ^* → Cu (hfac) + tmvs + Ar ^* … (3)

Next, FIG. 1 (4) and the following reaction formula (4)
As shown in (1), Cu (hfac) molecules generated by the dissociation of Cu (hfac) (tmvs) molecules collide with the argon-excited species to dissociate copper ions (Cu ⁺ ) from the Cu (hfac) molecules. Cu (hfac) + Ar ^* → Cu ⁺ + hfac + Ar ^* + e… (4)

As described above, under the plasma excitation of the mixed gas composed of Cu (hfac) (tmvs) and argon gas, Cu (hfac)
ac) (tmvs) and the reaction represented by the above-mentioned reaction formulas (3) and (4) at the same time as the reaction represented by the above-mentioned reaction formulas (1) and (2) due to collision between electrons and argon excited species. Occur, and these reactions produce copper ionic species, which deposit on the substrate.

The above-described reaction proceeds while being continuously accelerated via the electrons. For example, in the reaction formula (1), the electrons that collide with Cu (hfac) (tmvs) molecules are argon gas. May be considered as electrons released by the plasma excitation or electrons generated in the reaction formula (2).

That is, according to the present invention, copper ions are dissociated by the above-described continuous reaction, and at the same time, substantially all of the copper atoms contained in the source gas are used (precipitated). Good production efficiency (especially copper ions). Further, since copper ions deposited on the substrate are ionic species, they are efficiently deposited by, for example, an electric field generated on the substrate, and are substantially free of impurities (particularly carbon-based impurities), and are uniform and uniform. A thin film having a high density (nucleus generation density) is obtained. Furthermore, this reaction does not depend on the surface condition of the base material as a base, and it is possible to make it relatively easily adsorbed even on a base material or a side wall of a micropore having a surface state that is hardly adsorbed by copper atoms. is there.

Next, preferred embodiments of the method for forming a conductive thin film of the present invention and the conductive thin film of the present invention will be described.

First, in the method for forming a conductive thin film of the present invention, a mixed gas composed of the above-mentioned metal-containing gas (raw material gas) and a rare gas is excited by plasma, and this raw material gas and the rare gas excited species or / And the metal ions dissociated by collision with the electrons can be deposited on the substrate.

Examples of the plasma excitation method include a direct current type or high frequency type bipolar discharge type, a magnetic field focusing type (magnetron discharge type), an electrodeless discharge type, and an ECR (electron discharge).
Various plasma generation methods such as cyclotron resonance type can be applied, and the reaction shown in FIG. 1 proceeds even at a relatively low temperature.

Further, in the method for forming a conductive thin film of the present invention and the conductive thin film of the present invention, the deposited metal ions (that is, conductive thin films made of metal ions) are used as growth nuclei (seed layers). It is desirable to further deposit a metal (or metal layer) on this growth nucleus (or growth nucleus layer). According to the present invention, a conductive thin film having a uniform and sufficiently high nucleus density is formed. If a metal is further deposited using the conductive thin film as a growth nucleus, a thin film having a uniform and sufficiently high density can be obtained. A conductive thin film having excellent physical properties can be obtained.

The predetermined conductive thin film may be entirely formed of the metal ions. In particular, when the conductive thin film is formed on a substrate having fine pores, the deposition of the metal ions is not sufficient. Since the deposition of the metal ions on the side wall portions of the micropores may be insufficient, the deposition of the metal ions on the substrate is used as a growth nucleus, and the method is further performed by a method such as thermal decomposition with good step coverage. It is desirable to grow the metal. However, this growth nucleus can be formed into a film having a thickness of, for example, 10 nm or more at both the side wall and the bottom in a fine connection hole or the like. For example, the ratio of the side wall to the bottom is about 1: 3.

Specifically, using the deposited metal ions as growth nuclei, the metal may be further deposited on the growth nuclei by decomposition (for example, thermal decomposition) of a metal-containing gas (source gas). .

In this case, in particular, thermal decomposition (particularly, thermal decomposition CVD) of the metal-containing gas (source gas) is performed on the growth nucleus.
After further depositing the metal, additional metal can be deposited on the metal by physical deposition.
Further, the physical deposition method (so-called PVD method: physical
The vapor deposition may be, for example, a vacuum deposition method, a sputtering method, an ion plating method, or the like. According to the physical deposition method, impurities are less mixed and the growth nucleus has a high nucleus density. A conductive thin film having excellent physical properties is formed.

Alternatively, the deposited metal ions may be used as growth nuclei, and a metal may be deposited (formed) by electrolytic plating (electroplating). As described above, since the growth nuclei are uniform and have a high nucleus density, an electrolytic plating film having excellent physical properties can be formed even by the electrolytic plating method. When a film is further formed by an electrolytic plating method, a thermal decomposition CVD method, or a PVD method, the metal grown on the growth nucleus is:
The metal may be the same as the metal (metal ion) constituting the growth nucleus, or may be another metal.

In the method of forming a conductive thin film according to the present invention, it is preferable that the energy of the rare gas excited species or the electrons is not less than the ionization energy of the metal. For example, when a copper thin film is formed using the metal ions as copper ions, since the first ionization energy of copper is about 7.726 eV, the electrons and rare gas excited species in the above-described reaction formulas (1) and (3) are used. Is greater than 7.726 eV, the copper in the source gas is easily ionized.

Of course, it depends on the type and size of the reaction chamber for carrying out the above-mentioned reaction, but Cu (hfac) (tm
vs), a copper thin film is formed under plasma excitation of a mixed gas composed of a raw material gas composed of argon gas and a gas composed of argon gas.
Copper in the source gas can be ionized with a high frequency power of 500 W to 2000 W at rr to 10 Torr and a frequency of 13.56 MHz. Preferably, the supply amount of the source gas is 0.2 g / min to 0.8 g / min, and the supply amount of the argon gas is 100 sccm to 1000 sccm.

In the mixed gas, hydrogen gas (H
It is desirable to mix ₂ ). As shown in the above-mentioned reaction formula, for example, when Cu (hfac) (tmvs) is used as a raw material gas, after dissociating copper ions from Cu (hfac), hfac
It is believed that a product consisting of In particular, under plasma excitation, the product or its decomposition product may be mixed into the conductive thin film.Therefore, it reacts with the product or this decomposition product, and in order to easily exhaust this as a small molecule, hydrogen is used. It is preferable that a gas is previously mixed into the mixed gas, and carbon in the product and its decomposition product is extracted by the hydrogen.

It is desirable that the metal ions be attracted to the substrate by an electric field generated on the substrate (particularly, an electric field generated by applying a voltage to the substrate). According to the present invention, since the conductive thin film is formed by depositing metal ions, by imparting a certain directionality to the metal ions, the film forming rate is improved,
At the same time that the conductive thin film is efficiently formed, a substance other than the ionic species is suppressed from adsorbing to the substrate, and the surface of the substrate is hardly influenced by the surface condition of the substrate. It is easily deposited with a uniform and sufficient nuclear density.

Preferably, a barrier metal layer is provided on the substrate, and the metal ions are deposited on the barrier metal layer. Depending on the type of the base substrate, the metal ions may easily enter the base substrate and react with the metal ions, which may adversely affect the base substrate. It is preferable to form a conductive thin film made of the metal ions on the base through the intermediary.

Preferably, the present invention is applied to formation of an upper conductive layer among upper and lower conductive layers connected to the insulating layer provided on the base through connection holes. Of course, the method for forming a conductive thin film of the present invention can be applied to the formation of the upper and lower conductive layers. However, according to the present invention, the conductive thin film can be formed with good step coverage. It is suitably used for forming a thin film on a substrate having fine holes or the like.

Further, it is desirable that the metal (growth nucleus layer) is copper. Raw material gas used in the present invention,
It is desirable to be a gas at normal temperature and normal pressure. For example, when a copper thin film is formed as the conductive thin film, Cu (hfac) (tmvs) which is the above-mentioned β-ketonato copper (I), Cu (hf
ac) (btmsa) (copper hexafluoroacetylacetonate bistr
imethylsilylasetylnate), Cu (hfac) (copper (II) hexa
Complexes such as fluoroacetylacetonate) can be used. In addition, for example, (C ₅ H) having the structural formula shown in FIG.
F ₆ O ₂ ) Ag: P (CH ₃ ) ₃ (hexafluoroacetylacetonatosilver: tr
(CH ₃ ) ₂ Au (C ₅ HF ₆ O ₂ ) (dimethylhexaflu) having the structural formula as shown in FIG.
It is considered that divalent complexes such as silver (Ag) and gold (Au) such as oroacetylacetonatogold) also form gas at normal temperature and normal pressure. Therefore, a thin film made of silver or gold is also formed as the conductive thin film. It is considered possible.

Next, preferred embodiments of the method for manufacturing a semiconductor device of the present invention and the semiconductor device of the present invention will be described.

In the method of manufacturing a semiconductor device according to the present invention, a mixed gas comprising the metal-containing gas (source gas) and a rare gas is excited by plasma, and the source gas and the rare gas-excited species or / and the electrons are excited. And the metal ions dissociated by the collision can be deposited on the semiconductor substrate.

As described above, the plasma excitation method is, for example, a direct current or high frequency type bipolar discharge type, a magnetic field focusing type (magnetron discharge type), an electrodeless discharge type, or an ECR (electron cyclotron resonance). Various plasma generation methods such as a mold can be applied.

In the method of manufacturing a semiconductor device of the present invention and the semiconductor device of the present invention, metal ions (ie, a conductive thin film made of metal ions) deposited on the semiconductor substrate are used as growth nuclei (seed). It is desirable to further deposit a metal on the growth nucleus. According to the present invention, a conductive thin film having a uniform nucleus density and a sufficiently high density is formed. Thus, a conductive thin film having high density, high density, and excellent thin film properties can be obtained.

The predetermined conductive thin film may be formed entirely of the metal ions. In particular, the formation of the conductive thin film on a semiconductor substrate having a fine diameter connection hole (contact hole, via hole, etc.) Is performed, the deposition of the metal ions alone may not be sufficient on the side wall portions of the connection holes by simply depositing the metal ions. Therefore, the step coverage may be performed by using the deposits of the metal ions on the substrate as growth nuclei. It is desirable to further grow the conductive thin film by a method such as thermal decomposition.

More specifically, the metal may be further deposited on the growth nucleus by decomposition (for example, thermal decomposition) of a metal-containing gas (source gas) using the deposited metal ion as a growth nucleus. .

In this case, in particular, thermal decomposition (particularly, thermal decomposition CVD) of the metal-containing gas (raw material gas) is performed on the growth nucleus.
After further depositing the metal, additional metal can be deposited on the metal by physical deposition.
Further, the physical deposition method may be, for example, a vacuum deposition method, a sputtering method, an ion plating method, or the like. According to this physical deposition method, impurities are less mixed, and the nucleus density of the growth nucleus is reduced. Since it is high, a conductive thin film having excellent thin film properties is formed.

Alternatively, metal ions deposited on the semiconductor substrate may be used as growth nuclei, and a metal may be deposited (formed) by electrolytic plating (electroplating). As described above, since the growth nuclei have a uniform and high nucleus density, an electrolytic plating film having excellent physical properties can be formed by this electrolytic plating. In addition, the electrolytic plating method and the thermal decomposition CV
When the film is further formed by the D method or the PVD method, the metal grown on the growth nucleus may be the same metal as the metal (metal ion) forming the growth nucleus, or may be another metal. You may.

It is desirable that the energy of the rare gas excited species or the electrons be equal to or higher than the ionization energy of the metal. For example, when a copper thin film is formed using the metal ions as copper ions, since the first ionization energy of copper is about 7.726 eV, the electrons and rare gas excited species in the above-described reaction formulas (1) and (3) are used. Is greater than 7.726 eV, the copper in the source gas is easily ionized.

Of course, depending on the type and size of the reaction chamber for carrying out the above-mentioned reaction, Cu (hfac) (tm
vs), a conductive thin film made of copper is formed on a semiconductor substrate under plasma excitation of a mixed gas consisting of a raw material gas consisting of argon gas and an argon gas.
50 ° C to 250 ° C, pressure 0.1 Torr to 10 Torr
r, high frequency power of 13.56 MHz 500 W ~
At 2,000 W, copper in the source gas can be ionized. The supply amount of the raw material gas is 0.2 g /
min to 0.8 g / min, the supply amount of argon gas is 1
00 sccm to 1000 sccm is desirable.

The mixed gas contains hydrogen gas (H
It is desirable to mix ₂ ). As shown in the above-mentioned reaction equation, for example, when Cu (hfac) (tmvs) is used as a raw material gas, after dissociating copper ions from Cu (hfac), hf
It is believed that the product consisting of ac remains. In particular, under plasma excitation, the product or its decomposition product may be mixed into the conductive thin film.Therefore, it reacts with the product or this decomposition product, and in order to easily exhaust this as a small molecule, hydrogen is used. It is desirable to mix a gas in the mixed gas in advance.

It is desirable that the metal ions be attracted to the semiconductor substrate by an electric field generated on the semiconductor substrate (particularly, an electric field generating a voltage on the semiconductor substrate). According to the present invention, since the conductive thin film is formed by depositing metal ions, by giving a certain direction to the metal ions, it is possible to prevent substances other than ionic species from being adsorbed to the semiconductor substrate. In addition, the film formation rate is improved, and the conductive thin film is efficiently formed. At the same time, the conductive thin film is uniformly formed on the semiconductor substrate almost independently of the surface condition of the semiconductor substrate. And it is easily deposited with a sufficient nuclear density.

The conductive thin film may be formed as a wiring. In the field of semiconductor devices, miniaturization of wirings and the like, that is, high integration has been promoted for each generation. However, according to the method of manufacturing a semiconductor device of the present invention, a conductive thin film can be formed with good step coverage. Therefore, it is possible to sufficiently cope with such miniaturization.

Preferably, a barrier metal layer is formed on the semiconductor substrate, and the metal ions are deposited on the barrier metal layer. Depending on the type of the semiconductor substrate serving as the base, the metal ions may penetrate into the base base (for example, an interlayer insulating film or polysilicon wiring) and react (diffuse) with the base base.
It is desirable to form a conductive thin film made of the metal ions on the base via a barrier metal layer.

After an insulating layer is formed on the semiconductor substrate, connection holes for connecting upper and lower conductive layers are formed in the insulating layer, and at least the metal ions are deposited in the connection holes. It is desirable to form a conductive thin film as an upper conductive layer. That is, it is desirable that the conductive thin film is formed as an upper layer wiring of a semiconductor device having a multilayer wiring structure. Of course, the method of manufacturing a semiconductor device of the present invention can be applied to the formation of both the upper and lower conductive layers. However, according to the method of manufacturing a semiconductor device of the present invention, a conductive thin film can be formed with good step coverage. Therefore, it is suitably used particularly for forming a thin film on a semiconductor substrate having a fine diameter connection hole (via hole or contact hole) or the like.

Further, it is desirable that the metal (growth nucleus layer) is copper. Raw material gas used in the present invention,
It is desirable to be a gas at normal temperature and normal pressure. For example, when a copper thin film is formed as the conductive thin film, Cu (hfac) (tmvs) which is the above-mentioned β-ketonato copper (I), Cu (hf
ac) (btmsa) (copper hexafluoroacetylacetonate bistr
imethylsilylasetylnate), Cu (hfac) (copper (II) hexa
Complexes such as fluoroacetylacetonate) can be used. In addition, for example, (C ₅ H) having the structural formula shown in FIG.
F ₆ O ₂ ) Ag: P (CH ₃ ) ₃ (hexafluoroacetylacetonatosilver: tr
(CH ₃ ) ₂ Au (C ₅ HF ₆ O ₂ ) (dimethylhexaflu) having the structural formula as shown in FIG.
It is considered that divalent complexes such as silver (Ag) and gold (Au) such as oroacetylacetonatogold) also form gas at normal temperature and normal pressure. Therefore, a thin film made of silver or gold is also formed as the conductive thin film. It is considered possible.

In particular, as described above, copper has a lower specific resistance than aluminum, which is frequently used as a wiring (specifically, the specific resistance of Al is 2.7 μΩ · cm and the specific resistance of Cu is lower than that of aluminum). The resistance is 1.72 μΩ · cm), and it has a property of being resistant to electromigration, stress migration, and the like.

Next, a parallel plate type CVD apparatus which can be used in the method of forming a conductive thin film of the present invention and the method of manufacturing a semiconductor device of the present invention will be described with reference to FIG. Needless to say, the apparatus used in the method for forming the conductive thin film of the present invention and the method for manufacturing the semiconductor device of the present invention are the parallel plate type C type.
It is not limited to the VD device.

This apparatus comprises a lower electrode 23 on which a semiconductor substrate (or a substrate to be processed) 20 is arranged, and an upper electrode (shower electrode) 25 provided with a gas introduction hole for introducing a predetermined gas. CVD with parallel plate type electrode
Device. At the time of CVD film formation by plasma excitation, reactive plasma is generated between the upper electrode 25 and the lower electrode 23 from the high-frequency power supplies 24a and 24b by high-frequency discharge. Then, the metal ions are applied to the lower electrode 23 on the substrate 2 by an electric field generated by applying a predetermined voltage to the substrate.
0, for example, 350 KHz to 13.5
A 6 MHz variable high frequency power supply 24 a is connected, and a high frequency power supply 24 that generates, for example, 13.56 MHz RF is applied to an upper electrode 25 disposed opposite to the substrate 20.
b is connected.

Therefore, during CVD film formation, the gas inlet 21
Thus, for example, a source gas such as Cu (hfac) (tmvs) is introduced from the supply source 40 into the reaction chamber 27 via the vaporization section 41 together with a carrier gas 46 such as hydrogen gas, while a rare gas such as argon 47 and possibly a hydrogen gas 48 are supplied to the mass flow controllers 42 and 4
3, and a predetermined amount is introduced into the reaction chamber 27 via the valve 44. Here, for example, Cu (h
fac) (tmvs) is supplied at a rate of 0.2 g / min to 0.8 g / m.
in, the supply amount of the argon gas 47 is 100 sccm to 1
000 sccm, supply amount of hydrogen gas 48 is about 1000 c
c / min, and is supplied into the reaction chamber 27 from the gas introduction hole 26 provided in the upper electrode 25, and the semiconductor substrate 2
In accordance with the above-described reaction formula, a conductive thin film made of metal ions is formed on the substrate.

Further, as described above, for example, a temperature of 150 ° C. to 250 ° C. and a pressure of 0.1 Torr to
By setting the high frequency power to 500 W to 2000 W at 10 Torr and a frequency of 13.56 MHz, the deposition (deposition) reaction of metal ions based on the present invention shown in FIG. 1 can be easily realized.

[0068]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited to the following examples.

Embodiment 1 In this embodiment, a plasma CVD apparatus having a parallel plate type CVD reaction chamber shown in FIG. 12 was used, and an opening was made to face a tungsten (W) or copper (Cu) metal wiring. A conductive thin film made of copper is formed on a semiconductor substrate having a connection hole (via hole) based on the above-described method for forming a conductive thin film and a method for manufacturing a semiconductor device.

First, although not shown, a predetermined pattern of tungsten-based or copper-based metal wiring 2 is formed on a base 1 made of, for example, an SiO ₂ insulating film through predetermined processing, and an organic compound-based interlayer is formed thereon. After forming the insulating film 3, the interlayer insulating film 3 is formed by using photolithography and etching.
Then, a via hole 4 opened to face the metal wiring 2 is formed.

Next, as shown in FIG.
Is formed on the surface to be treated containing tantalum (Ta), tantalum nitride (TiN) based on a long distance sputtering method, or tungsten nitride (W ₂ N) based on a plasma CVD method. .

Next, the substrate on which the barrier metal layer 5 is formed is placed near the gas inlet 21 above the reaction chamber 27 by RF.
It is arranged in a CVD apparatus (see FIG. 12) provided with electrodes (corresponding to the upper electrode 25).

Next, a mixed gas A composed of Cu (hfac) (tmvs) and argon is introduced from a gas introduction hole 26 provided in the reaction chamber 27, and a high-frequency power source installed near the gas introduction hole is introduced. (RF 13.56 MHz) 24b is used to excite the mixed gas A by RF discharge under the following plasma excitation conditions to generate a reactive plasma of the mixed gas A. The RF power applied at this time is set so that the electrons (and argon-excited species) in the plasma have the first ionization energy of copper or more. Such conditions can be confirmed by measuring the emission of copper ions in the plasma and the ion current.

<Plasma Excitation Conditions> Temperature: 150 ° C. to 250 ° C. Pressure: 0.1 Torr to 10 Torr RF (13.56 MHz) Power: 500 W to 2000 W Cu (hfac) (tmvs) Gas Supply Rate: 0.2 g / min 0.8 g / min Argon gas supply: 100 sccm to 1000 sccm Hydrogen gas supply: 1000 cc / min

Under the plasma excitation of the mixed gas containing Cu (hfac) (tmvs) and argon, Cu (hfac) (tmvs) + e → Cu (hfac) + tmvs + e… (1) Cu (hfac) + e → Cu ⁺ + hfac + 2e… (2) Simultaneously, Cu (hfac) ) (tmvs) + Ar ^* → Cu (hfac) + tmvs + Ar ^* ... (3) Cu (hfac) + Ar ^* → Cu ⁺ + hfac + Ar ^* + e ... (4) and argon A collision dissociation reaction with the excited species occurs, and a copper ion species 6 is generated by these reactions (see FIG. 4).

Then, as shown in FIG. 5, the copper ion species 6 is deposited as a Cu growth nucleus 7 having a thickness of 20 nm to 50 nm on the barrier metal layer 5 including the via hole 4.
At this time, a DC bias (especially a negative bias) is applied to the substrate 1 side.
Is applied, the copper ion species can be more efficiently deposited on the surface to be processed (on the barrier metal layer 5).

Then, as shown in FIG. 6, a hydrogen gas as a carrier gas and Cu (hfac) (tmvs) as a source gas containing copper (Cu source gas) 8 are supplied to a CVD reaction chamber 27.
As shown in FIG. 7, a Cu layer 9 is formed by thermal decomposition of Cu (hfac) (tmvs). In the thermal decomposition reaction at this time, it is considered that the Cu source gas 8 composed of Cu (hfac) (tmvs) is adsorbed on the Cu growth nucleus 7 and copper is deposited by the following thermal decomposition reaction. Cu (hfac) (tmvs) → Cu (hfac) + tmvs… (A) 2 Cu (hfac) → Cu + Cu (hfac) ₂ … (B)

The thermal decomposition may be performed, for example, by: <Thermal decomposition conditions> Temperature: 150 ° C. to 250 ° C. Pressure (total pressure): 0.1 Torr to 50 Torr Cu (hfac) (tmvs) Supply rate: 0.2 g / min ０．８0.8 g / min Hydrogen gas supply rate: 1000 cc / min.

As described above, by exciting the mixed gas of Cu (hfac) (tmvs) and argon gas by plasma,
A conductive thin film made of copper ions having a uniform and high nucleus density is efficiently formed on the substrate to be processed. Furthermore, Cu (hfac)
When (tmvs) is introduced and thermally decomposed, Cu is deposited with the conductive thin film as a growth nucleus, copper is uniformly deposited on the entire surface, and a conductive thin film made of copper having excellent thin film properties is formed. . Further, Cu growth nucleus 7 shown in FIG.
The u layer 9 can be observed with an electron microscope or the like from the difference in the amount of impurities contained and the difference in the chemical structure.

When a conductive thin film (growth nucleus) made of copper ions is used as a seed layer in the electrolytic plating method, the growth nucleus is deposited to a thickness of about 20 nm to 50 nm, and then, based on the electrolytic plating method. Copper can be deposited. Further, the via hole itself can be embedded with a conductive thin film made of copper ions.

Embodiment 2 In this embodiment, a conductive thin film made of copper ions is formed on the basis of the above-described method for forming a conductive thin film and the method for manufacturing a semiconductor device.
The copper wiring is formed by combining the copper thin film formation based on the D method and the reflow method. In the present embodiment, the steps up to the step shown in FIG. 6 are the same as those in the first embodiment.

First, although not shown, similarly to the first embodiment, a tungsten-based or copper-based metal wiring 2 having a predetermined pattern is formed on a base 1 made of, for example, an SiO ₂ insulating film through a predetermined process. Organic compound-based interlayer insulating film 3
Is formed, a via hole 4 opened to the metal wiring 2 is formed in the interlayer insulating film 3 by using photolithography and etching.

Next, as shown in FIG.
Is formed on the surface to be treated containing tantalum (Ta), tantalum nitride (TiN) based on a long distance sputtering method, or tungsten nitride (W ₂ N) based on a plasma CVD method. .

Next, the substrate on which the barrier metal layer 5 is formed is placed near the gas inlet 21 above the reaction chamber 27 by RF.
It is installed in a CVD apparatus (see FIG. 12) in which an electrode (corresponding to the upper electrode 25) is installed.

Next, a mixed gas A consisting of Cu (hfac) (tmvs) and argon is introduced from a gas introduction hole 26 provided in the reaction chamber 27, and a high frequency power supply installed near the gas introduction hole is introduced. (RF 13.56 MHz) 24b is used to excite the mixed gas A by RF discharge under the following plasma excitation conditions to generate a reactive plasma of the mixed gas A. The RF power applied at this time is such that electrons (and argon excited species) in the plasma have a first ionization energy of copper or more. This condition can be confirmed from the measurement of the emission of copper ions in the plasma and the measurement of the ion current.

<Plasma Excitation Conditions> Temperature: 150 ° C. to 250 ° C. Pressure: 0.1 Torr to 10 Torr RF (13.56 MHz) Power: 500 W to 2000 W Cu (hfac) (tmvs) Gas supply amount: 0.2 g / min. 0.8 g / min Argon gas supply: 100 sccm to 1000 sccm Hydrogen gas supply: 1000 cc / min

Under the plasma excitation of the gas mixture containing Cu (hfac) (tmvs) and argon, Cu (hfac) (tmvs) + e → Cu (hfac) + tmvs + e… (1) Cu (hfac) + e → Cu ⁺ + hfac + 2e… (2) Simultaneously, Cu (hfac) ) (tmvs) + Ar ^* → Cu (hfac) + tmvs + Ar ^* ... (3) Cu (hfac) + Ar ^* → Cu ⁺ + hfac + Ar ^* + e ... (4) and argon A collision dissociation reaction with the excited species occurs, and a copper ion species 6 is generated by these reactions (see FIG. 4).

Then, as shown in FIG. 5, the copper ion species 6 is deposited as a Cu growth nucleus 7 having a thickness of 20 nm to 50 nm on the barrier metal layer 5 including the via hole 4.
At this time, a DC bias (especially a negative bias) is applied to the substrate 1 side.
, The copper ion species 6 can be more efficiently
Can be deposited on the surface to be processed (on the barrier metal layer).

Next, as shown in FIG. 6, a hydrogen gas as a carrier gas and Cu (hfac) (tmvs) as a source gas containing copper (Cu source gas) 8 are supplied to a CVD reaction chamber 27.
As shown in FIG. 7, Cu (hfac) (tmvs) is thermally decomposed to form a Cu layer 11 by pyrolysis. At this time, the thermal decomposition reaction causes Cu (hfac) (tmvs)
It is considered that the Cu source gas 8 consisting of is adsorbed and copper is deposited by the following thermal decomposition reaction. Cu (hfac) (tmvs) → Cu (hfac) + tmvs… (A) 2 Cu (hfac) → Cu + Cu (hfac) ₂ … (B)

The thermal decomposition is performed, for example, under the following conditions: <Thermal decomposition conditions> Temperature: 150 ° C. to 250 ° C. Pressure (total pressure): 0.1 Torr to 50 Torr Cu (hfac) (tmvs) Supply rate: 0.2 g / min ０．８0.8 g / min Hydrogen gas supply rate: 1000 cc / min. By this thermal decomposition reaction, as shown in FIG.
The u film 11 is formed on the Cu growth nucleus 7.

Next, the substrate to be processed is set in a PVD chamber (not shown), and based on a long distance sputtering method, as shown in FIG. ℃ ~ 400 ℃
To form a film.

Next, 5 to 5 in the same PVD chamber
By heating (substrate temperature 350 ° C. to 400 ° C.) for 10 minutes, the Cu growth nucleus 7 and the Cu layer 11
The Cu layer 12 is reflowed by VD, and the via hole 4 is filled with the Cu layer 13 as shown in FIG.

After depositing the Cu layer 12 based on the long-distance sputtering method, another apparatus is used to set the Cu layer 12 in a hydrogen gas atmosphere.
By heating the substrate to be processed at a substrate temperature of 350 ° C. to 400 ° C., the Cu layer can be reflowed to fill the via hole 4.

Embodiment 3 In this embodiment, when a copper thin film is buried by applying an electrolytic plating method to a connection hole (via hole) opened toward a tungsten-based or copper-based metal wiring, the above-described conductivity is obtained. Applying a method of forming a thin film and a method of manufacturing a semiconductor device,
This is to form a seed layer for electrolytic plating. In the present embodiment, up to the step shown in FIG.
This is similar to the first embodiment.

First, although not shown, as in the first embodiment, a tungsten-based or copper-based metal wiring 2 having a predetermined pattern is formed on a base 1 made of, for example, an SiO ₂ insulating film through a predetermined process. Organic compound-based interlayer insulating film 3
Is formed, a via hole 4 opened to the metal wiring 2 is formed in the interlayer insulating film 3 by using photolithography and etching.

Next, as shown in FIG.
Is formed on the surface to be treated containing tantalum (Ta), tantalum nitride (TiN) based on a long distance sputtering method, or tungsten nitride (W ₂ N) based on a plasma CVD method. .

Next, the substrate on which the barrier metal layer 5 has been formed is placed in a CVD apparatus (FIG. 1) in which an RF electrode (corresponding to the upper electrode 25) is installed in the gas inlet 21 above the reaction chamber 27.
2).

Next, a mixed gas A comprising Cu (hfac) (tmvs) and argon is introduced from a gas introduction hole 26 provided in the reaction chamber 27, and a high-frequency power source installed near the gas introduction hole is introduced. Using (RF 13.56 MHz) 24b, the mixed gas A is plasma-excited by RF discharge under the following plasma excitation conditions to generate reactive plasma of the mixed gas A. The RF power applied at this time is such that electrons (and argon excited species) in the plasma have a first ionization energy of copper or more. This condition can be confirmed from the measurement of the emission of copper ions in the plasma and the measurement of the ion current.

<Plasma Excitation Conditions> Temperature: 150 ° C. to 250 ° C. Pressure: 0.1 Torr to 10 Torr RF (13.56 MHz) Power: 500 W to 2000 W Cu (hfac) (tmvs) Gas supply rate: 0.2 g / min. 0.8 g / min Argon gas supply: 100 sccm to 1000 sccm Hydrogen gas supply: 1000 cc / min

Under the plasma excitation of this mixed gas containing Cu (hfac) (tmvs) and argon, Cu (hfac) (tmvs) + e → Cu (hfac) + tmvs + e… (1) Cu (hfac) + e → Cu ⁺ + hfac + 2e… (2) Simultaneously, Cu (hfac) ) (tmvs) + Ar ^* → Cu (hfac) + tmvs + Ar ^* ... (3) Cu (hfac) + Ar ^* → Cu ⁺ + hfac + Ar ^* + e ... (4) and argon A collision dissociation reaction with the excited species occurs, and a copper ion species is generated by these reactions (see FIG. 4).

Then, as shown in FIG. 5, the copper ion species is deposited as a Cu growth nucleus 7 having a thickness of 20 nm to 50 nm on the barrier metal layer 5 including the via hole 4. At this time, by applying a DC bias (particularly a negative bias) to the substrate 1 side, the copper ion species can be more efficiently deposited on the surface to be processed (on the barrier metal layer).

Next, as shown in FIG. 6, a hydrogen gas as a carrier gas and Cu (hfac) (tmvs) as a raw material gas containing copper (Cu raw material gas) 8 were introduced into a CVD reaction chamber 27.
Then, as shown in FIG. 10, a Cu layer 11 is formed by thermal decomposition of Cu (hfac) (tmvs) by thermal decomposition.
At this time, the thermal decomposition reaction causes Cu (hfac) (tmv
It is considered that the Cu source gas 8 composed of s) is adsorbed and copper is deposited by the following thermal decomposition reaction. Cu (hfac) (tmvs) → Cu (hfac) + tmvs… (A) 2 Cu (hfac) → Cu + Cu (hfac) ₂ … (B)

The thermal decomposition may be performed, for example, by: <Thermal decomposition conditions> Temperature: 150 ° C. to 250 ° C. Pressure (total pressure): 0.1 Torr to 50 Torr Cu (hfac) (tmvs) Supply rate: 0.2 g / min ０．８0.8 g / min Hydrogen gas supply rate: 1000 cc / min. By this thermal decomposition reaction, FIG.
As shown in (1), a Cu film 11 having a thickness of 50 n to 100 nm used as a seed layer for electrolytic plating is formed on the Cu growth nucleus 7.

Next, the substrate to be processed through the steps up to this point is disposed in an apparatus (not shown) for forming a copper film by electrolytic plating, and a rare gas (argon gas) is flowed into the plating chamber at a flow rate of 10 L / min. While under the following electroplating conditions,
As shown in FIG. 10, the via hole 4 is buried by a copper electrolytic plating method. <Electroplating conditions> CuSO ₄ : 67 g / L H ₂ SO ₄ : 170 g / L HCl: 70 ppm Additive: surfactant Solution temperature: 20 ° C. Current (DC): 9 amps

As described above, the mixed gas consisting of the source gas containing copper and the rare gas is plasma-excited, and the energy of the electrons and the rare gas-excited species during the plasma excitation is made equal to or more than the ionization energy of copper. It is possible to efficiently generate copper ion species, and Cu ions are deposited on the substrate to be processed at a uniform and high nucleus density.

Thereafter, when a raw material gas containing copper is thermally decomposed using a conductive thin film made of copper ions uniformly deposited on the substrate to be processed as a growth nucleus, copper having a sufficient nuclear density is further deposited. Further, a copper electrolytic plating film having a sufficient nucleus density is formed on the copper thin film by the thermal decomposition.

In this embodiment, a C ion having a uniform and sufficient nucleus density is obtained by using copper ion species generated under plasma excitation.
Since a u-growth nucleus can be formed, a conductive thin film of Cu, which can be provided as a seed layer for electrolytic plating, for example, can be deposited uniformly and with a sufficient nucleus density on the entire surface of a semiconductor substrate.

Although the present invention has been described with reference to specific embodiments, the present invention is not limited to these embodiments.

For example, as shown in FIG. 11, a barrier metal layer 33, a growth nucleus 34 composed of copper ions, a thermal decomposition CVD method or a sputtering method is provided through a contact hole 36 provided in an interlayer insulating film 32 on a semiconductor substrate 31. Alternatively, the Cu layer 35 can be formed by PVD.

The apparatus for forming a conductive thin film (growth nucleus) made of copper ions is not limited to the above-mentioned parallel plate type CVD apparatus, but is an inductively coupled plasma CVD apparatus.
Any CVD apparatus capable of plasma excitation such as an apparatus and an ECR plasma CVD apparatus can be applied.

Further, the present invention is not limited to the formation of a conductive thin film made of copper ions, but can be used to form a metal such as gold or silver which can become a gas at normal temperature and normal pressure. In the first to third embodiments, at the time of depositing copper ions, a hydrogen gas for suppressing the incorporation of carbon as an impurity may be introduced at a predetermined ratio. Further, in addition to argon, helium, neon, krypton,
Xenon or the like can also be used. Further, in addition to Cu (hfac) (tmvs) as the source gas containing metal, for example, Cu
(hfac) (btmsa) (copper hexafluoroacetylacetonate bi
predetermined temperature, such as strimethylsilylasetylnate)
A gaseous source gas can be used under pressure.

[0112]

According to the method for producing a conductive thin film of the present invention, a source gas containing a metal such as copper, silver, or gold is mixed with a rare gas excited species such as argon, krypton, or xenon, and / or an electron. To generate ions of the metal and deposit the metal ions on the substrate, so that the metal ions are efficiently generated, and the metal ions are uniformly and sufficiently nucleated on the substrate. Is deposited.

The conductive thin film of the present invention is formed according to the above-described method of forming the conductive thin film of the present invention, and comprises a growth nucleus layer composed of metal ions deposited on a substrate,
It has a laminated structure composed of a metal layer deposited on the growth nucleus. The growth nucleus layer composed of the metal ions,
As described above, since the metal layer is formed with a uniform and sufficient nuclear density, the metal layer deposited thereon is also a metal layer having a sufficient nuclear density, and the growth nuclear layer and the metal layer Is a conductive thin film having excellent thin film physical properties.

According to the method of manufacturing a semiconductor device of the present invention,
Forming a conductive thin film on the semiconductor substrate through a step of generating ions of the metal by causing rare gas excited species and / or electrons to act on a gas containing the metal and depositing the metal ions on the semiconductor substrate; Therefore, the metal ions are efficiently generated, and even in a semiconductor substrate having fine connection holes and the like, the metal ions are deposited with a uniform and sufficient nuclear density.

According to the semiconductor device of the present invention, the conductive thin film having a laminated structure composed of a growth nucleus layer made of metal ions deposited on a semiconductor substrate and a metal layer deposited on this growth nucleus layer is formed as described above. Since the growth nucleation layer is formed on the semiconductor substrate and the growth nucleation layer is formed with a uniform and sufficient nuclear density, the metal layer deposited thereon also becomes a metal layer having a uniform and sufficient nuclear density. The conductive thin film having a stacked structure of the growth nucleus layer and the metal layer becomes a conductive thin film having excellent thin film properties.

[Brief description of the drawings]

FIG. 1 is a drawing describing a chemical formula and the like showing a collision dissociation reaction between a source gas and electrons and argon excited species generated when depositing copper ions according to the present invention.

FIG. 2 is a drawing describing chemical formulas and the like of a gas containing a metal that can be used in the method for forming a conductive thin film of the present invention.

FIG. 3 is a schematic cross-sectional view of a semiconductor device showing one process step when forming a conductive thin film including a growth nucleus made of copper ions based on Embodiment 1 of the present invention.

FIG. 4 is a schematic cross-sectional view of the semiconductor device showing another process step when forming a conductive thin film.

FIG. 5 is a schematic cross-sectional view of the semiconductor device showing another process step when forming a conductive thin film.

FIG. 6 is a schematic cross-sectional view of the semiconductor device showing another process step when forming a conductive thin film.

FIG. 7 is a schematic cross-sectional view of the semiconductor device showing another process step when forming a conductive thin film.

FIG. 8 is a schematic cross-sectional view of a semiconductor device showing one process step of forming a conductive thin film including a growth nucleus made of copper ions based on Embodiment 2 of the present invention.

FIG. 9 is a schematic cross-sectional view of the semiconductor device showing another process step when forming a conductive thin film.

FIG. 10 is a schematic cross-sectional view of a semiconductor device showing one process step of forming a conductive thin film including a growth nucleus made of copper ions based on Embodiment 3 of the present invention.

FIG. 11 is a schematic cross-sectional view showing a conductive thin film including a growth nucleus made of copper ions formed on a semiconductor substrate including a contact hole according to the present invention.

FIG. 12 is a schematic view of a main part of a plasma CVD apparatus that can be used in the present invention.

FIG. 13 is a drawing describing chemical formulas and the like showing a thermal decomposition reaction of a raw material gas containing copper.

[Explanation of symbols]

1, 20: substrate, 2: lower wiring, 3, 32: interlayer insulating film, 4: via hole, 5, 33: barrier metal, 6: copper ion species, 7, 34: Cu growth nucleus, 8: Cu source gas,
9, 13, 35: Cu layer, 11: Cu layer by thermal decomposition,
12 ... Cu layer by PVD, 21 ... gas inlet, 22 ...
Gas outlet 23, lower electrode 24 DC power supply 25
Upper electrode, 26 gas introduction hole, 27 reaction chamber, 30 semiconductor substrate, 36 contact hole, 38 Cu layer by electrolytic plating

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C25D 5/34 C25D 5/34 H01L 21/285 H01L 21/285 C 301 301Z 21/768 21/90 A

Claims (42)

[Claims] 1. A method for forming a conductive thin film, comprising the step of causing a rare gas excited species and / or electrons to act on a gas containing a metal to generate ions of the metal and depositing the metal ions on a substrate. 2. A mixed gas comprising a metal-containing gas and a rare gas is plasma-excited, and the metal ions dissociated by colliding the metal-containing gas with the rare gas-excited species and / or the electrons are formed. The method for forming a conductive thin film according to claim 1, wherein the conductive thin film is deposited on the substrate. 3. The method for forming a conductive thin film according to claim 1, wherein the deposited metal ions are used as growth nuclei, and a metal is further deposited. 4. The method for forming a conductive thin film according to claim 3, wherein the deposited metal ions are used as growth nuclei, and the metal is further deposited by decomposition of a gas containing the metal. 5. The method for forming a conductive thin film according to claim 4, wherein the metal is further deposited by thermal decomposition of the gas containing the metal, and then the metal is further deposited on the metal by a physical deposition method. 6. The method for forming a conductive thin film according to claim 3, wherein the deposited metal ions are used as growth nuclei, and a metal is further deposited by an electrolytic plating method. 7. The method for forming a conductive thin film according to claim 1, wherein the energy of the rare gas excited species or the electrons is equal to or more than the ionization energy of the metal. 8. Mixing hydrogen gas in the mixed gas,
A method for forming a conductive thin film according to claim 2. 9. The method according to claim 1, wherein the metal ions are attracted to the substrate by an electric field generated by applying a voltage to the substrate. 10. The method according to claim 1, wherein the metal ions are deposited on a barrier metal layer. 11. The conductive thin film according to claim 1, wherein the conductive thin film is applied to form an upper conductive layer among upper and lower conductive layers connected through a connection hole to an insulating layer provided on the base. Forming method. 12. The method according to claim 1, wherein the metal is copper. 13. A conductive thin film having a laminated structure composed of a growth nucleus layer made of metal ions deposited on a substrate and a metal layer deposited on this growth nucleus. 14. The conductive thin film according to claim 13, wherein the metal layer is deposited on the growth nucleus layer by decomposition of a gas containing a metal. 15. The conductive thin film according to claim 14, wherein the metal layer is deposited by thermal decomposition of the gas containing the metal, and the metal layer is further deposited on the metal layer by a physical deposition method. 16. The conductive thin film according to claim 13, wherein said metal layer is deposited by an electrolytic plating method. 17. The conductive thin film according to claim 13, wherein the growth nucleus layer is formed on a barrier metal layer. 18. The conductive thin film according to claim 13, wherein the conductive thin film is used as an upper conductive layer among upper and lower conductive layers connected via connection holes to an insulating layer provided on the base. 19. The method according to claim 1, wherein the growth nucleus layer is made of copper.
3. The conductive thin film according to 3. 20. A rare gas-excited species or / and / or a gas containing a metal.
And forming a conductive thin film on the semiconductor substrate through a step of generating ions of the metal by acting electrons and depositing the metal ions on the semiconductor substrate. 21. A mixed gas comprising a gas containing a metal and a rare gas is plasma-excited, and the metal ions dissociated by colliding the gas containing the metal with the rare gas-excited species and / or the electrons are generated. The method for manufacturing a semiconductor device according to claim 20, wherein the semiconductor device is deposited on the semiconductor substrate. 22. The method of manufacturing a semiconductor device according to claim 20, wherein the deposited metal ions are used as growth nuclei, and a metal is further deposited. 23. The method of manufacturing a semiconductor device according to claim 22, wherein the deposited metal ions are used as growth nuclei, and the metal is further deposited by decomposition of a gas containing the metal. 24. The method of manufacturing a semiconductor device according to claim 23, wherein after further depositing the metal by thermal decomposition of the gas containing the metal, the metal is further deposited on the metal by a physical deposition method. 25. The method according to claim 22, wherein the deposited metal ions are used as growth nuclei, and a metal is further deposited by electrolytic plating.
3. The method for manufacturing a semiconductor device according to item 1. 26. The method of manufacturing a semiconductor device according to claim 20, wherein the energy of the rare gas excited species or the electrons is equal to or more than the ionization energy of the metal. 27. The method according to claim 21, wherein a hydrogen gas is mixed into the mixed gas. 28. The method according to claim 20, wherein the metal ions are attracted to the semiconductor substrate by an electric field generated by applying a voltage to the semiconductor substrate. 29. The method according to claim 20, wherein a wiring is formed as the conductive thin film. 30. The method according to claim 20, wherein a barrier metal layer is formed on the semiconductor substrate, and the metal ions are deposited on the barrier metal layer. 31. An insulating layer is formed on the semiconductor substrate,
21. The semiconductor according to claim 20, wherein connection holes for connecting upper and lower conductive layers are formed in the insulating layer, the metal ions are deposited in at least the connection holes, and the conductive thin film is formed as an upper conductive layer. Device manufacturing method. 32. The method of manufacturing a semiconductor device according to claim 31, wherein said conductive thin film is an upper layer wiring of a multilayer wiring. 33. The method according to claim 20, wherein the metal is copper. 34. A conductive thin film having a laminated structure composed of a growth nucleus layer made of metal ions deposited on a semiconductor substrate and a metal layer deposited on this growth nucleus layer is formed on said semiconductor substrate. A semiconductor device. 35. The metal layer is deposited on the growth nucleus layer by decomposition of a gas containing a metal.
2. The semiconductor device according to 1. 36. The semiconductor device according to claim 35, wherein the metal layer is deposited by thermal decomposition of the gas containing the metal, and a metal layer is further deposited on the metal layer by a physical deposition method. 37. The semiconductor device according to claim 34, wherein said metal layer is deposited on said growth nucleus by an electrolytic plating method. 38. The semiconductor device according to claim 34, wherein said conductive thin film is formed as a wiring. 39. The semiconductor device according to claim 34, wherein a barrier metal layer is formed on the semiconductor substrate, and the growth nucleus layer is formed on the barrier metal layer. 40. The conductive layer according to claim 34, wherein the conductive thin film is formed as an upper conductive layer among upper and lower conductive layers connected to the insulating layer formed on the semiconductor substrate through connection holes. Semiconductor device. 41. The semiconductor device according to claim 40, wherein said conductive thin film is an upper layer wiring of a multilayer wiring. 42. The growth nucleation layer is made of copper.
4. The semiconductor device according to item 4.