JP3315211B2 - Electronic components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to IC and other electronic parts, about the particular electromigration resistance and the like, electronic components with improved reliability in the metal wiring.

[0002]

2. Description of the Related Art In recent years, the integration of electronic components, for example, memory-integrated circuits such as D-RAMs has been remarkably increased, and accordingly, miniaturization of wiring for electrically connecting each element has been inevitable. Has been lost. Due to this miniaturization, higher current density and higher operating temperature are required for wiring, and at the same time, it is required to improve electromigration resistance, which is inversely proportional thereto, and to ensure high reliability.
At present, a metal thin film of Al or an Al alloy is most frequently used for this wiring. Although the electromigration resistance of such a metal wiring has been improved by adding a trace amount of a transition metal such as Cu or Ti or by forming a knot-shaped grain boundary structure (bamboo structure) of bamboo by crystal grain growth,
It is difficult to secure the reliability of 0.1-micron level wiring only by improving this resistance. According to recent research, it has been clarified that the resistance to electromigration or the resistance to stress migration due to tensile stress induced in wiring is significantly improved by using single crystal wiring, and the crystallinity of the metal thin film is reduced as much as possible. Approaching a single crystal is considered as a means for realizing high reliability.

At present, in electronic components such as a memory integrated circuit, metal wiring has a barrier layer or not.
It is formed on the surface of an amorphous thin film typified by an iO ₂ interlayer insulating film. Therefore, it is not possible to form a metal thin film having high crystallinity by using a so-called epitaxial crystal growth method of forming a single crystal thin film by taking over the base crystal arrangement, and as a result, it has extremely excellent electromigration resistance. However, it has been difficult to obtain highly reliable metal wiring.

[0004]

As described above, conventional electronic components have a problem that it is difficult to obtain highly reliable metal wiring.

The present invention, in order to solve such a problem, and an object thereof is to provide an electronic component having a high metal interconnect reliability.

[0006]

The most problematic point in obtaining a metal thin film having high crystallinity is that many crystal nuclei, which are the starting points of the growth of the thin film at the initial stage of the deposition, are simultaneously formed on the base to be deposited. It is formed. Crystal growth of these crystal nuclei proceeds due to absorption of deposited particles or coalescence of nuclei during the film growth stage, but there is a limit to the size that crystal grains can grow by this mechanism, and ultimately The resulting thin film becomes a polycrystal having a different orientation arrangement for each crystal grain. Therefore, in order to form a thin film having high crystallinity in a large area, it is important to suppress generation of nuclei as much as possible.

[0007] Considering nucleation from the classical discussion,
The surface between the deposited material represented by the formula (1) and the underlying material
Interfacial energy correlation, γf ≦ γs−γi (1) γf: Surface energy of deposited material γs: Surface energy of base material γi: Interfacial energy is established (wetting angle is zero), so-called layered growth is established. , The guided nucleation density becomes zero.

[0008] Here, the interface energy γi is 1. 1. lattice matching between the deposited material and the underlying material;
It is said to be governed by the bond energy between atoms between the deposited material and the underlying material. However, when an amorphous material is used as a base material as in the case of forming a metal wiring in a semiconductor device, it is not clear what is governed by the interface energy and the surface energy of the base material.

The inventors of the present invention have conducted intensive studies and have examined the atomic arrangement correlation at the interface in detail. As a result, even when the amorphous substance is used as the base, the atomic or molecular arrangement at the interface is not the same as that of the deposited substance. It was found that it had an important effect on the crystal arrangement. That is, it has been revealed by the diffraction phenomenon of an X-ray, an electron beam, or the like that the structure of an amorphous substance is not completely disordered, and a regular structure in a short range is established. As described above, the magnitude of the interfacial energy, which determines the atomic arrangement at the interface, is determined by the degree of lattice matching in two or three periods, where the size of this lattice is the size of the halo pattern that appears in diffraction measurements of amorphous materials. It is almost equal to the interatomic distance corresponding to the vertex. Therefore, in the present invention, it has been found that by making this interatomic distance coincide with a certain interplanar spacing of atoms or molecules of a deposited material, a reduction in interfacial energy is realized, and as a result, a thin film having extremely high crystallinity can be formed. Was done. That is, the present invention
An amorphous thin film formed on a substrate, comprising a highly oriented metal wiring formed on the surface, the interatomic distance corresponding to the peak of the halo pattern appearing in the diffraction measurement of the amorphous thin film, It is an object of the present invention to provide an electronic component in which predetermined crystal planes defined by a distance between first adjacent atoms of a metal wiring are substantially matched.

At this time, it is most preferable that the interatomic distance ds of the amorphous thin film is matched with the plane distance df of the metal wiring, but a slight deviation can be tolerated, and | df−ds | / ds ≦ 0.
Desirably 25. The specific crystal plane defined by the distance between the first adjacent atoms of the metal wiring is, for example, (111), (200), (220) for the fcc structure, or (2) for the bcc structure.
(00), (110), (002), (110) in the hexagonal structure,
It is not necessarily the orientation plane. The degree of matching varies depending on the composition of the amorphous thin film. At this time, by containing the main elements constituting the metal wiring in the amorphous thin film,
More alignment can be achieved.

Another factor that governs the interfacial energy is the binding energy as in the case of the crystal-crystal system. That is, the interface energy can be reduced by increasing the binding energy. For this purpose, the metal element M which is a main component of the metal wiring may be contained in the amorphous thin film. Alternatively, an element containing an element A that forms an intermetallic compound with the element M in an amorphous thin film, or an element having a full solid solution with the element M or having a completely solid solution region in the amorphous thin film It is desirable to contain B. As the metal element M which is a main component of the metal wiring, Al, Cu, Au, Ag, W, or the like is usually used.

On the other hand, the surface energy γs of the underlying material is
The larger the size, the easier it is for the deposited material to grow in layers. However, since the surface energy is measured near the melting point of the substance to be measured, it is practically impossible to measure the surface energy of the amorphous substance in which the crystallization temperature <the melting point. Then, as a result of examining what is affected by the surface energy of the amorphous material, it was found that there is a correlation with the surface energy in the crystalline state. That is, in order to increase the surface energy γs of the underlying material, it is preferable that the surface energy in the crystalline state of the material constituting the amorphous thin film is higher than the surface energy of at least the material constituting the metal wiring which is a deposited material. Therefore, it is desirable that the melting point correlated with the surface energy is high. However, the surface energy of a substance composed of a plurality of elements is a value obtained by averaging the surface energies of the respective constituent elements by the atomic ratio.

The substrate in the present invention is not particularly limited, and may be an ordinary semiconductor substrate such as a Si substrate or a GaAs substrate, or a glass substrate provided with ITO or the like. Its shape may be flat or have grooves.

As the amorphous thin film formed on the substrate,
Amorphous single metal, alloy, conductive compound, or the like is used. Further, as described above, the elements M, A,
A composition containing at least one kind of B is desirable, and in view of the ability to form an amorphous phase, a transition metal, a metalloid (metalloid), a semiconductor alloy or a compound is more preferable.
Specifically, a metal element M, a group IIIB element (Sc, Y,
La series), Group IVB elements (Ti, Zr, Hf), Group VB elements (V, Nb, Ta), Group VIB elements (Cr, Mo,
W), Group VIII elements (Fe, Ru, Os, Co, Rh, I
r, Ni, Pd, Pt,) and B, C, N, O, P, S
i, a composition containing two or more types selected from Ge. Further, a compound having a perovskite oxide composition may be used as the amorphous thin film.

In the present invention, the amorphous thin film is RH
Diffraction measurement typified by electron diffraction or X-ray diffraction such as EED, etc., may be sufficient as long as a diffuse diffraction intensity, in other words, a halo peak is observed. There is no problem even if diffraction lines from microcrystals such as intermetallic compounds appear. Furthermore, it is not necessary that the whole is amorphous, and only the surface of the crystalline thin film may be amorphous.

The thickness is preferably thin, but is preferably in the range of 10 to 1000 Å so as not to expose the substrate. However, even if it is more than that, it is possible to improve the crystallinity of the metal thin film formed thereon.

As shown in FIG. 2, this amorphous thin film 3 is used not only as a base of a single layer wiring but also as a base of a metal wiring 2 constituting each wiring layer in a multilayer wiring. It is also used as a base for a vertical conductive connection portion, for example, a via 4 or a through hole. Further, it may be formed directly on the substrate 1 or may be formed via an insulating layer 5 such as a thermal oxide film of SiO ₂ , a barrier layer 6 such as Ti or TiN, an adhesion layer or an intervening layer such as another wiring. Good. At this time, these intervening layers may be flat or have grooves. Note in the figure, 5'insulating film 7 of SiO ₂ or the like serving as the element isolation region is doped layer.

Further, in the present invention, the number of hillocks generated by heat treatment or electromigration can be drastically reduced by forming an amorphous thin film as a base of the metal wiring.

That is, it is generally considered that a hillock is generated by a compressive stress induced in a thin film or a metal wiring, and an excess volume that generates a compressive stress is released as a hillock. At this time, the hillock generation point is the stress concentration portion, and the resistance to the deformation of the thin film here determines the presence or absence of the hillock. In the conventional W or TiN thin film coating, since these thin films are made of polycrystal, the crystal grain boundary portion becomes a stress concentration portion and cracks are generated, and hillocks are generated therefrom.

The present inventors have found that the above-mentioned weaknesses specific to polycrystals can be avoided by making them amorphous.
That is, by using the amorphous thin film, the deformation resistance at the stress concentration portion, which is the hillock generation point, was increased, and the hillock generation was significantly suppressed. This effect is particularly remarkable when the above-described elements M, A, and B are contained in the amorphous thin film. In this case, since the bonding force between the main element constituting the metal wiring and the element in the amorphous thin film increases, the compressive stress concentration generated in the metal wiring can be uniformly dispersed in the amorphous thin film. It becomes possible, and as a result, it is considered that the frequency of occurrence of hillocks is drastically reduced.

From the viewpoint of preventing the occurrence of hillocks as described above, the amorphous thin film does not need to be particularly formed as a base of the metal wiring, but only needs to cover a part of the metal wiring. For example, as shown in FIGS. 3A, 3B, 3C, and 3D, the amorphous thin film 101 may be formed above or around the metal wiring 100. Further, when the amorphous thin film is formed on the metal wiring, the effect of preventing hillocks is caused by the bonding force between atoms between the amorphous thin film and the metal wiring as described above. It also depends on the surface state of the metal wiring before forming the crystalline thin film. For example, in the case of a metal wiring mainly composed of Al, the surface thereof is usually made of Al so that it can be confirmed by reflection high-speed electron diffraction (RHEED).
Covered with oxide. That is, A once exposed to the atmosphere
When the wiring surface is observed by RHEED, only a halo pattern peculiar to the amorphous is obtained due to the amorphous oxide film formed on the surface. On the other hand, if this surface layer is removed by Ar sputtering or the like, a ring or oriented diffraction pattern resulting from the Al thin film can be obtained. Therefore, when an amorphous thin film is formed after realizing such an Al metal surface, the ability to suppress hillocks is further improved.

Further, when Cu as a low-resistance wiring material is used for metal wiring, O
₍₂₎ Oxidation resistance to asher is a problem. At this time, in particular, the amorphous thin film containing Ti, Zr, Hf, V, Ta, and Nb suppresses diffusion of oxygen through the crystal grain boundary into the film and improves the oxidation resistance of Cu. .

Further, in the present invention, by forming an amorphous thin film between the substrate and the metal wiring, it is possible to suppress the reaction due to the grain boundary diffusion which occurs in the prior art.
Above all, since an Al amorphous alloy as an amorphous thin film does not form a high-resistance reaction layer with a metal wiring mainly composed of Al, a highly reliable contact portion can be provided. Furthermore, by using an alloy containing one of Ta, Nb, V, Mo, and W as an Al amorphous alloy, it is possible to perform fine processing simultaneously with metal wiring mainly composed of Al. Can reduce the number of steps. At this time, the content of Al is preferably 15 at% or more in order to achieve amorphousness, and more preferably 15 to 80 at% in order to keep the surface energy of the amorphous thin film high. Such Al amorphous alloy, in particular _{Ta x Al 1-x (0.20} ≦ x ≦ 0.85), Nb x A
l _1-x (0.20 ≦ x ≦ 0.85), V _x Al
_1-x (0.20 ≦ x ≦ 0.60), W _x Al _1-x (0.
15 ≦ x ≦ 0.50), Mo _x Al _1-x (0.25 ≦ x
≦ 0.80). The Cu amorphous alloy is C
A highly reliable contact portion having good adhesion to a metal wiring mainly composed of u can be provided. Specific examples of such Cu amorphous alloy include Ti _x Cu _1-x (0.18 ≦ x ≦
0.70), Zr _x Cu _1-x (0.18 ≦ x ≦ 0.7
_{0), Hf x Cu 1-} x (0.20 ≦ x ≦ 0.70), Y
_x Cu _1-x (0.10 ≦ x ≦ 0.53), Ta _x Cu
_1-x (0.20 ≦ x ≦ 0.80). Further, in a metal wiring mainly composed of Cu which requires a low resistance, V _x Co _1-x (0.15 ≦ x ≦ 0.80), N x
b _x Cr _1-x (0.25 ≦ x ≦ 0.45), Nb _x Co
_{1-x (0.22 ≦ x ≦} 0.55), Ta x Cr
_{1-x (0.25 ≦ x ≦} 0.40), Ta x Co 1-x
(0.25 ≦ x ≦ 0.45), Cr _x Co _1-x (0.5
0 ≦ x ≦ 0.70), Mo _x Co _1-x (0.20 ≦ x ≦
0.60), W _x Co _1-x (0.20 ≦ x ≦ 0.60)
Such an amorphous alloy can be preferably used because it does not generate a solid solution with a metal wiring mainly composed of Cu and can suppress an increase in resistance due to a reaction. In addition, the stability of the amorphous alloy can be further improved by containing a so-called metalloid element such as Si, Ge, P, and B in these amorphous alloys.

Further, the amorphous thin film may have a multilayer structure in which different amorphous substances are stacked. At this time, it is preferable that the outermost surface is made of an amorphous alloy or the like having a high surface energy as described above.
SiO ₂ containing P, polyimide, TEOS, SiN or the like may be used.

The metal wiring formed on the amorphous thin film as described above is composed of highly oriented crystals having a high crystallinity oriented in a specific plane direction. It is preferable that the angle between the normal direction of the densest surface and the normal direction of the bottom surface of the metal wiring is within 80 °. Further, in the case of a single crystal, the angle formed between the closest surface and the longitudinal direction of the wiring is preferably 20 ° or less. At this time, the crystal structure of the metal wiring is f
In the case of the cc structure, the (111) plane which is the densest plane, bcc
(110) plane in the case of the structure, and (00) plane in the case of the hexagonal structure.
01) A metal wiring is formed on each surface so as to be nearly parallel to the wiring longitudinal direction. Also, in consideration of the degree of freedom in wiring design, it is desirable to form a metal wiring with the densest surface being the upper surface, that is, the densest surface orientation.

This metal wiring can be used not only for a single-layer wiring but also for a multi-layer wiring and a conductive connection portion in the vertical direction, that is, a via or a through hole. In particular, the continuity of the crystal orientation of the metal wiring can be maintained and the reliability can be improved even when the vertical conductive connection portion and the upper and lower wiring layers are made of different materials. Also, this metal wiring
A multilayer structure in which different kinds of metals or metals having different crystal states are stacked may be used.

As a wiring material of such a metal wiring, pure Al, pure Cu,
Pure Au, pure Ag, Al-Cu, Al-Ti, Al-C
r, Al-Ta, Al-Mg, Al-In, Al-L
i, Cu-Be, Cu-Ag, Au-Pt, Au-A
g, Au-Pd, Au-Cu, pure W having a bcc structure
In the case of an alloy, the solute addition amount is desirably in the complete solid solution range. In this case, Si is 1w
It may be contained up to about t%. Also, by alloying,
It is also possible to reduce the surface energy of the metal wiring (surface energy γf of the deposited material).

Further, in such a metal wiring, for example, a material having a lower melting point than the wiring material and not forming an intermetallic compound with an element constituting the metal wiring at a grain boundary, an upper layer, and a lower layer thereof,
In addition, an element having an affinity with the substrate or the intervening layer may be smaller than the element constituting the metal wiring. For example, A
When using l or Al alloy for metal wiring, Ga, In,
At least one element of Cd, Bi, Pb, Sn, and Tl, and at least one element of Pb and Tl in the case of Cu or a Cu alloy.

Further, the metal wiring may be covered with a high melting point metal or a silicide, nitride, oxide or carbide of the high melting point metal.

The electronic component of the present invention having such a structure can be manufactured as follows.

First, an insulating layer, a barrier layer, an adhesion layer, and the like are provided on a substrate, if necessary, and then the plane spacing of a specific crystal plane of a metal wiring formed thereon is formed by a known deposition method such as a sputtering method. An amorphous thin film is formed so as to match with. next,
Form metal wiring without breaking vacuum. Or,
If the amorphous thin film is once exposed to the atmosphere after formation,
After cleaning the surface by bias sputtering or the like, a metal wiring is formed. However, when the amorphous thin films are B, C, N,
When the amorphous thin film contains O or the like and the high surface energy state of the amorphous thin film is maintained even in an oxygen or nitrogen atmosphere, an oxide layer or the like is hardly formed on the surface even when the amorphous thin film is exposed to the atmosphere. May be formed without cleaning. As the film forming method for forming the metal wiring, it is preferable that the physical vapor deposition be a sputter film, a bias sputter film, or an ion beam film. Also,
As the chemical vapor deposition, for example, in the case of the AlCVD method, T
Alkali aluminum such as IBA or alkyl aluminum hydride such as DMAH is used as a source gas,
It is desirable to form a film by a thermal CVD method. At this time,
Mixing Si or Cu into the source gas during film formation,
After the film formation, alloying may be performed by laminating by ion implantation or sputtering or the like and performing heat treatment.

Further, similarly, an amorphous thin film and metal wiring may be formed thereon via an insulating layer or the like to form a multilayer wiring. At this time, a crystal may be grown from the seed by applying a heat treatment after the film formation. In this case, when the seed is, for example, Si, after a dilute HF treatment is finally performed as a pretreatment, washing is not performed, or washing is performed in an ultrapure water environment having a dissolved oxygen content of 10 ppb or less. It is desirable to dry in nitrogen below -90 ° C.

Further, the surface of the film-forming substrate may be processed and a graphoepitaxy method may be used. In the present invention, it has been described that the metal thin film formed on the underlying amorphous thin film having a high surface energy has extremely high crystal orientation and is oriented in a specific plane direction. This is considered because if the surface energy of the base is high, the wetting angle of the deposited nucleus with the base is small. For example, in the case of Al, the (111) plane having a low energy is stably grown. However, at this time, the in-plane orientation of the growth nucleus was random, and further control of the in-plane orientation was essential to further improve the wiring reliability. On the other hand, in the present invention, by using the amorphous thin film having a groove formed on the surface as a base, not only the crystal orientation of the metal thin film to be formed but also the controllability of the in-plane orientation are sufficiently improved. Here, the amorphous thin film may have the bottom and side walls of the groove made of the same material or different materials. In particular, the bottom and side walls of the groove may be made of different materials to form a metal thin film. It is desirable to utilize the difference in surface energy between these parts during film formation. According to such a configuration, the deposited material preferentially nucleates and grows in a portion having a higher surface energy in the bottom and side wall portions of the groove, while the other portions have a lower surface energy. This is because, as a result of receiving another axis orientation control at the boundary with the above, a metal thin film close to a single crystal can be formed. Further, in this case, a metal thin film having high crystallinity can be obtained even if the amorphous thin film is crystallized by heat treatment before or after the metal thin film is formed.

At this time, the shape of the groove is desirably a strip shape, or a state in which any one of rectangles, squares and equilateral triangles or a combination thereof is arranged in a large number, and each side is arranged in parallel with an accuracy of ± 5 degrees or less. Also, the area of each groove is preferably equal to or less than the average crystal area of the metal wiring, and the area of the protrusion is preferably equal to or less than the average crystal area of the metal wiring like the groove.
In the case of a strip-shaped groove, it is desirable that the width of the groove and the width of the convex portion are not more than the average crystal grain size of the metal wiring.

When forming a metal wiring on an amorphous thin film,
It is important that no surface oxide film is formed on the amorphous thin film as described above. As a method for removing the surface oxide film of the amorphous thin film, it is desirable to perform plasma etching immediately before forming the metal thin film, and after the etching, the degree of vacuum is 1 × 10 5
^It is important to keep it below ^-6 Torr. As a method for forming the metal thin film, any of a CVD method and a PVD method may be used, but it is desirable to increase the substrate temperature to promote the migration of the vapor-deposited particles. In addition to resistance heating, electron beam irradiation or laser beam irradiation may be used. Further, an oblique vapor deposition method in which a vaporized particle stream is incident on the substrate at an angle is also desirable.

Further, the metal wiring made of highly oriented crystal as described above is made of Al or Al alloy, Cu or C
When depositing a conductor layer made of a u-alloy to form a metal thin film, it can also be realized by supplying an element having a small surface energy before or during the deposition of the conductor layer.

More specifically, for example, Al or Al
When a metal wiring made of an alloy is formed, Ga, I
When forming a metal wiring made of one or more elements selected from the group consisting of n, Cd, Bi, Pb, Sn and Tl, Cu or Cu alloy, it is selected from the group consisting of Pb and Tl. One or two types of elements are supplied. Here, the correlation between γf and γi when one or more atomic layers are formed by supplying such an element is shown in FIG.
Think using. In FIG. 1, 1 is a substrate, 5 is an insulating layer made of a thermal oxide film, 50 is a control layer, and 2 is a metal wiring.
In this case, since the surface energy of the elements constituting the control layer is small, the sum of γf and γi is smaller in the state of FIG. 1B than in the state of FIG. Therefore, when the above-described element is supplied onto a substrate and a conductor layer serving as a metal wiring is deposited thereon, the element diffuses to the surface of the conductor layer in order to minimize free energy. As a result, the surface energy of the deposited material is apparently reduced, and the crystal growth approaches the layered growth. As a result, any of the insulating layer, the barrier layer, the adhesion layer, and the amorphous thin film layer whose base is formed on the substrate is formed. Even so, a metal thin film having high crystallinity can be formed. This is particularly remarkable when the element is supplied during the deposition of the conductor layer, and it is sufficient if the supply amount of the element is 以上 atomic layer or more. Further, by supplying the element, the surface diffusion of the deposited material is remarkably promoted, and the crystal grain size is also increased. This will be described with reference to FIG . FIG. 28 (a) shows that Al is deposited on the SiO ₂ insulating layer by 50.
FIG. 28B is a surface SEM photograph when 0 angstrom is deposited, and FIG. 28B is a surface SEM photograph when one atomic layer of Bi is supplied during Al deposition. As shown in the figure, when Bi is supplied during the deposition of the conductor layer, when Bi is not supplied, the thin film form (film aggregation) obtained by heat treatment in a vacuum at 400 ° C. for 3 hours causes the substrate to be heated. And can be obtained immediately after deposition.

When a barrier layer made of a compound or an alloy on a substrate, an adhesion layer, or the like is formed as a base layer, and then a heat treatment is performed to deposit a conductor layer, a pretreatment for depositing the conductor layer is as follows. By etching the underlayer with plasma containing at least one element constituting the compound or alloy, a metal thin film having high crystallinity and orientation can be formed. This is because the etching prevents the surface of the underlayer made of a compound or an alloy from being oxidized and eliminates active species on the surface to form a stable interface. For example, when the underlayer is a nitride, it is desirable to etch the surface with plasma in which nitrogen is mixed with an inert gas and deposit a conductor layer thereon, and at this time, the conductor layer is deposited in a vacuum. Although it is desirable to carry out the etching continuously, it may be exposed to the atmosphere for a short time. Further, in the etching, after the etching with the mixed gas, it may be exposed to plasma of only the elements constituting the compound or the alloy. Further, it is desirable that these etchings are performed with a bias potential applied to the substrate, and the voltage is desirably −100 V or less. The method of depositing the conductive layer thereafter is not limited to a physical vapor deposition method such as a sputter deposition method or a resistance heating vapor deposition method, and may be any of various CVD methods. At this time, the substance forming the conductor layer is Si
Or WSi, MoSi, pure Al, Al alloy, pure Cu,
Any of Cu alloy, W, Au, and Ag may be used. In addition, Al
For alloys: Al-Cu alloy, Al-Cr alloy, Al-M
A g alloy is particularly desirable. Alternatively, these materials may be formed in a layered manner.

For example, in the case of the AlCVD method, it is desirable to form a film by a thermal CVD method using alkyl aluminum hydride such as TIBA or alkyl aluminum hydride such as DMAH as a source gas. At this time, alloying may be performed by mixing Si, Cu, or the like into the source gas during the film formation, or by laminating and heat-treating the film by ion implantation or sputtering after the film formation.

By improving the crystallinity of the metal thin film in this way, it is possible to obtain an electronic component having excellent metal wiring reliability such as anti-stress migration and anti-migration.

In the present invention, as described above, after the amorphous component and the metal wiring are sequentially formed on the substrate to manufacture the electronic component of the present invention, a further crystal using the metal wiring composed of highly oriented crystals is formed. A predetermined heat treatment may be performed for the purpose of grain growth. At this time, there is no problem even if the amorphous thin film is crystallized or disappears due to the heat treatment, but rather the crystallinity is enhanced due to the grain growth of the highly oriented crystal, so that the reliability of the metal wiring is further improved. Can be improved.

Although the present invention relates to improving the reliability of metal wiring as described above, the same technique can be applied to a capacitor in an electronic component, an electrode portion of a resistance heating element, and the like. .

For example, when the lower electrode of the capacitor is formed, the distance between the atoms corresponding to the peak position of the halo pattern appearing in the diffraction measurement of the underlying amorphous thin film and the distance between the first adjacent atoms of the lower electrode are obtained. Since the specified interplanar spacing of the specific crystal planes is substantially matched, the interfacial energy between the amorphous thin film and the lower electrode is reduced, and a lower electrode having extremely high crystallinity can be formed. Therefore, the crystallinity of the dielectric thin film formed thereon is also improved.

Further, by using an amorphous thin film as the resistance heating element, it is possible to obtain uniform electric resistance characteristics with little change over time. Further, when an electrode film is deposited on this amorphous thin film so that the interatomic distance of the amorphous thin film and the surface spacing of the electrode are substantially matched, the crystallinity of the electrode is improved, and the deterioration is suppressed even when a large current is applied. .

[0045]

The present invention will be described below in detail with reference to examples.

[0046] (Embodiment 1) FIG. 4, the present embodiment will be described with reference to FIG.

4000 Å thermal oxide film (Si
Using a 6-inch silicon wafer substrate 1 having an insulating layer 5 made of O ₂ ), an amorphous thin film 3 and a metal wiring 2 were sequentially formed by sputtering as described below. That is, first, FIG.
An AlTa film was formed as the amorphous thin film 3 by the multi-target sputtering apparatus shown in FIG. The sputtering conditions are shown below. In FIG. 4 , 8 is a high frequency power supply, 9 is a matching circuit, 1
0 indicates a mass flow controller, and 11 indicates a target. Sputtering method: RF magnetron method Target: AlTa mosaic target of 100 mmφ (concentric) Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas Pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 500 Å

As a result of the composition analysis, the formed film was Al ₄₀ T
a ₆₀ (the numerical values are the same in the atomic composition ratio hereinafter). X-ray diffraction showed that the film was amorphous, and the interatomic distance ds corresponding to the apex of the halo pattern was 2.34 angstroms. On the other hand, the spacing df of (111) in Al is 2.
Since it is 34 angstroms, | df-ds | /
ds = 0 was obtained, and it was found that the main element constituting the metal wiring was contained in the amorphous thin film and a proper composition could be matched with the plane spacing of the specific crystal plane of the metal wiring. In this example, a mosaic target was used, but a simultaneous sputtering method using a binary target,
Even when a film was formed by a method such as laminating each element, an amorphous thin film was similarly obtained.

Next, Al ₄₀ Ta ₆₀ without breaking vacuum.
Al was sputtered on the film. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ Al target Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

When the orientation and crystallinity of the Al film thus formed were evaluated by X-ray diffraction, the half width (orientation half width) of the (111) rocking curve was 1.2 °, and the (hhh) Bragg reflections (eg (200), (2
20) were not observed at all.

Then, the thus-formed film having the layer structure shown in FIG. 5 was processed into a four-terminal pattern having a width of 0.5 μm and a length of 1 mm, and an electromigration (EM) test was performed. The test conditions were a wiring temperature of 200 ° C and a current density of 2 × 10 ⁶
A / cm ² . As a result, it was confirmed that good reliability was obtained without breaking even after 1000 hours of energization. Here, when the electric resistance during the EM accelerated test rises by 10% of the value immediately after the start of the test, it is regarded as a wire breakage, and the same applies to the following.

Similarly, as a combination of (amorphous thin film / metal wiring), (W ₇₅ N ₂₅ / Al), (Pt ₂₁ Zr ₇₉ / P
t), (Cu ₅₀ Ti ₅₀ / Cu), (Ag ₅₅ Cu ₄₅ / A
g) and (Fe ₈₀ B ₂₀ / Fe) were prepared, and the half-width values of orientation were evaluated in the same manner. Al, Pt, Cu, Ag
Are (111) orientations and half-widths are 1.3 °, 1.4 °, and 1.8 °, respectively.
° and 1.6 °, and Fe was (110) -oriented and the half-width at orientation of (110) reflection was 1.7 °.

Example 2 In the same manner as in Example 1, Ni ₃₀
An amorphous thin film made of Ta ₇₀ (melting point 1500 ° C.) was formed, and a metal wiring made of Al (melting point 660 ° C.) was formed thereon. That is, the amorphous thin film has a higher melting point than the metal wiring,
It contains an element capable of forming an intermetallic compound with a main element constituting a metal wiring. At this time, Ni ₃₀ Ta ₇₀
The distance ds between atoms corresponding to the apex of the halo pattern of 2.
33 angstrom, Al (111) spacing df = 2.34
Approximately consistent with Angstrom. When this was evaluated in the same manner as in Example 1, good crystallinity with a (111) half-width at orientation of 0.9 ° was observed, and in the EM test, good reliability was obtained without breaking after 1000 hours of conduction. It was confirmed that.

Similarly, as a combination of (amorphous thin film / metal wiring), (Pd ₈₀ Si ₂₀ / Al), (Ag ₅₅ Cu ₄₅ /
Al) and (W ₇₀ Zr ₃₀ / Al) were prepared and evaluated in the same manner.
1.9 °, 1.8 °, and 1.2 °.

Example 3 An amorphous thin film made of Co ₈₀ Zr ₉ Nb ₁₁ which is a Co-based alloy was formed in the same manner as in Example 1, and a metal wiring made of Al was formed thereon. At this time, the interatomic distance ds corresponding to the apex of the halo pattern of Co ₈₀ Zr ₉ Nb ₁₁ was 2.04 Å, and Al
(200) The distance between planes is substantially matched to the distance df = 2.02 angstroms. When this was evaluated in the same manner as in Example 1,
(111) Orientation and good crystallinity were observed, and it was also confirmed in the EM test that good reliability was obtained without breaking after 1000 hours of energization. Similarly, as a combination of (amorphous thin film / metal wiring), (Co ₈₀ Zr ₈ Nb ₁₂
/ Al), (Co ₈₅ Zr ₆ Nb ₉ / Al), (Co ₈₈ Z
r ₃ Ta ₉ / Al) and (Co ₉₀ Hf ₆ Pd ₄ / Al) were prepared and evaluated in the same manner.
1) It was confirmed that good crystallinity with an orientation half width of 1.2 ° was obtained.

After forming a polycrystalline TiN / Ti layer as a barrier layer 6 on the insulating layer 5 as shown in FIG. 6 , an amorphous thin film 3 (Co ₈₀ Zr ₉ Nb ₁₁ ) is formed thereon. Al metal wiring 2 is formed on each of the above-described structure, the structure once exposed to the air as shown in Table 1, and the structure after the bias sputtering of Ar, and the like. The orientation was evaluated by the half width of an Al (111) rocking curve by X-ray diffraction using CuKα radiation.
As shown in Table 1, those without an amorphous thin film and those without exposure to air and not subjected to Ar bias sputtering have significantly reduced crystal orientation.

[Table 1]

(Example 4) As in Example 1, Table 2
The amorphous thin film and metal wiring shown in FIG. As shown in Table 2, in this embodiment, an amorphous thin film having a larger surface energy than a metal wiring in a crystalline state is used.

[Table 2]

In each case, the spacing ds corresponding to the apex of the halo pattern in the amorphous thin film and the distance d between the lattices of Al
It is substantially consistent with f. When these were evaluated in the same manner as in Example 1, as shown in Table 2, (111) orientation and good crystallinity were observed in all cases.
It was confirmed that good reliability was obtained without breaking during energization for 00 hours.

At this time, the T used as the amorphous thin film
Borides such as iB ₂ , and others, such as carbides and nitrides, are preferable because of their high surface energy. The surface energy at this time is calculated by an approximate expression: ΔE ^sv = Yλ ² / 4π
² X ₀ △ E ^sv: surface energy Y: Young's modulus lambda: (approximated by X ₀₎ distance over which the force between atoms X _0: can be determined by interatomic distance.

At the same time, as a comparative example, a metal wiring was formed directly on SiO _{2 in the} same manner as in Example 1. A is the nearest distance between atoms ds corresponding to the top of the halo pattern of SiO ₂ and A
It does not substantially match the l (111) plane distance df, and the surface energy of SiO ₂ is smaller than that of Al. When this was evaluated in the same manner as in Example 1, the (111) orientation half width was as large as 8.2 °, and the wiring was broken within 10 hours in the EM test under the same conditions.

[0061] The present embodiment will be described with reference to Example 5 FIG.

In this embodiment, a vertical conductive connection portion, that is, a via 4 as shown in FIG. 7 is formed. Specifically, first, a 1000 angstrom thick SiO ₂ thermal oxide film is formed as an insulating layer 5 on a Si substrate 1 and then Al, Cu, W or M is formed as a lower metal wiring 2 ′.
A thin film composed of oSi ₂ was deposited at 4000 Å. An SiO ₂ interlayer insulating film 5 is formed on this thin film by thermal CVD.
'Was deposited for 3000 Å. This interlayer insulating film 5
', A via 4 (or through hole) having a diameter of 50 μm was formed by a normal PEP and RIE process.

Next, W is formed in the via 4 by using the selective CVD method.
Was embedded and flattened by etch back, and then a Co ₈₀ Zr ₉ Nb ₁₁ thin film was formed as an amorphous thin film 3 according to the present invention by 200 Å by sputtering. Subsequently, after performing RF plasma cleaning of Ar on the surface of the Co ₈₀ Zr ₉ Nb ₁₁ once exposed to the atmosphere, a pure Al thin film was deposited as a metal wiring 2 by 4,000 Å by sputtering, and the crystal orientation of the Al thin film was changed to CuKα. The evaluation was made based on the half width of an Al (111) rocking curve measured using a line. At this time, the incident X-ray was narrowed down to φ50 μm by a collimator, and the change and distribution of the half width in the vicinity of the via were examined.
° and good crystal orientation.

[0064] The present embodiment will be described with reference to (Example 6) FIG.

After forming the vias 4 in the same manner as in the fifth embodiment,
As shown in FIG. 8 , Ni62Nb38
It was formed by sputtering at 00 angstrom. As a result, as shown in FIG. 8 , the side wall of the via was slightly thinned, but a NiNb film was formed conformally. On top of this, a pure Al thin film is continuously formed as a metal wiring 2 by sputtering.
00 angstrom was formed. When evaluated in the same manner as in Example 5, a half width of 1.35 ° was uniformly obtained.

[0066] The present embodiment will be described with reference to Example 7 FIG.

After forming the via 4 in the same manner as in the fifth embodiment,
As shown in FIG. 9 , Al ₄₀ Ta ₆₀ was formed as an amorphous thin film 3 by sputtering. At this time, by providing a collimator between the substrate on which the via 4 is formed and the target, the straightness of the deposited particles is improved. As a result, almost no amorphous layer is formed on the side wall of the via 4 and the via A 100 Å AlTa amorphous thin film 3 was formed on the bottom surface of the substrate 4 and on the interlayer insulating film 5 '. Once exposed to the atmosphere,
After performing RF bias sputter cleaning of Ar,
A pure Al thin film was deposited as the metal wiring 2 by 4000 Å by sputtering. When evaluated in the same manner as in Example 5, a half value width of 1.1 ° was uniformly obtained.

[0068] The present embodiment will be described with reference to Example 8 Fig.

As shown in FIG . 10 , when forming the lower metal wiring _{2 ′} , first, the insulating layer 5 made of a SiO ₂ thermal oxide film is formed.
After forming Al40Nb60 as an amorphous thin film 3 'thereon,
A lower metal wiring 2 'made of pure Al was continuously deposited in a thickness of 4000 angstroms. The half width of the rocking curve of the lower metal wiring 2 ′ was 1.2 °. An SiO ₂ interlayer insulating film 5 ′ is formed on the Al lower metal wiring 2 ′ in the same manner as in the fifth embodiment.
And via 4 were formed. Next, the via 4 was selectively filled with Al by a thermal CVD method using TIBA (triisobutylaluminum) as a source gas. The Al embedded in the via 4 inherits the crystal orientation of the underlying Al and exhibits the same half width of the rocking curve as that of the lower metal wiring 2 '. Subsequently, A was continuously formed as an amorphous thin film 3.
The l ₄₀ Nb ₆₀ was 250 Å is deposited by sputtering. After once exposing to the atmosphere and performing bias cleaning with RF plasma of Ar, sputtering or TIB
Al film as metal wiring 2 by thermal CVD method using A
4000 Å deposited. The crystal orientation distribution of this Al film is uniform, and its rocking half width is 1.2 °.
Met. Before the Al deposition, the amorphous thin film 3 at the via 4 is removed by a usual PEP process and ion milling process. Is uniform and the half width is
It was unchanged at 1.2 °.

On the other hand, as a comparative example, when the amorphous thin film according to the present invention was not interposed, the amorphous S
The half value width of Al on iO ₂ was about 8 °, and the uniformity of the orientation was poor. In particular, the disorder of the orientation at the via portion was remarkable.

[0071] (Embodiment 9) FIG. 11, the present embodiment will be described with reference to FIG. 12.

[0072]FIG.As shown in FIG.
_Two Using an Si substrate 1 having an insulating layer 5 made of
First, amorphous SiO_Two Amorphous by sputtering on top
After depositing the thin film 3 for 1000 angstroms (FIG.
(B)) The remaining amorphous portion except for the portion where the wiring is formed
The thin film 3 was removed by etching (FIG.
(C)). On top of this, a 5000 angstrom film thickness
Having amorphous SiO_Two An insulating layer 5 made of
(FIG.(D)). Next, the SiO on the amorphous thin film 3_Two
Groove for removing only by etching and embedding wiring
Formed (FIG.(E)). As a result, the bottom of the groove is not
The crystalline thin film 3 was obtained. In this embodiment, the width of the groove,
The metal wiring width was 0.8 μm. The depth of the groove is 4000
Angstrom. Groove for wiring prepared in this way
A low-energy ion beam on a substrate 1 having
After removing the oxide film on the surface of the amorphous thin film 3 by irradiation,
Sobutyl aluminum ((C_Four H₉)_Three Al) as raw material gas
Aluminum is deposited by a thermal CVD method
Got line 4 (FIG.(F)). Aluminum only in grooves
Substrate growth should be kept below 300 ° C
Realized by Table 3 shows that the amorphous thin film 3 was made of Al amorphous
Aluminum deposition in trench when alloy is formed on the bottom of trench
Speed is shown against substrate temperature. As an Al amorphous alloy
Al₃₀Ta₇₀, Al₄₀Nb₆₀, Al₅₀V₅₀I chose. Ma
In order to confirm the selective growth, the SiO_Two With
Table 3 also shows the presence or absence of selective growth. Further comparative examples
Amorphous SiO_Two , Polycrystalline silicon, polycrystalline
Of aluminum deposition rate and selective growth with silver formation
Indicates presence / absence. Amorphous SiO compared to on Al amorphous alloy_Two 
Sufficient aluminum at 300 ° C or less on polycrystalline silicon
Embedded aluminum cannot be deposited
The surface shape of the unit is also bad. The deposition rate on polycrystalline silver is also A
l Smaller than on an amorphous alloy, and in the wiring longitudinal direction
Of aluminum is discontinuous with respect to
A spot was seen.

Next, Table 4 shows the result of examining the crystallinity of the selectively embedded aluminum by X-ray diffraction.
Here, the orientation of aluminum was evaluated by measuring the half width of the rocking curve of the Al (111) diffraction peak. The aluminum buried in the grooves based on the Al amorphous alloy is a (111) highly oriented film with a (111) half width of about 1 °.

When the aluminum buried in the groove having the bottom surface of the Al amorphous alloy was observed with a transmission electron microscope, the aluminum crystal grain size was almost the same as the wiring width.
It was about μm, and it was found that these (111) crystal grains were in contact with each other in the longitudinal direction of the wiring by sub-grain boundaries (small-angle grain boundaries). Further, it was confirmed that there was a region where a single crystal grain was present over a length of 10 μm or more in the longitudinal direction of the wiring, though it was partial. This indicates that an aluminum wiring made of a single crystal, which is more excellent in stress migration resistance and electromigration resistance than an Al wiring made of a (111) highly oriented crystal, is partially realized.

Finally, FIG. 12 shows the results of an acceleration test performed to examine the electromigration resistance of the aluminum embedded wiring formed in this embodiment. The test conditions are a substrate temperature of 150 ° C. and a current density of 1 × 10 ⁷ A / cm ² . It was confirmed from the change over time in the rate of change in resistance that the conventional aluminum wiring had extremely high reliability compared to the case where the aluminum wiring was broken within one hour.

[Table 3]

[Table 4]

[0076] The present embodiment will be described with reference to Example 10 FIG.

As shown in FIG . 13 , a SiO ₂ insulating layer 5 is formed on the semiconductor substrate 1 on which the functional element 31 is formed by using the CVD method, and a region to be a contact portion is removed by etching to form a connection hole. 32 are provided. In order to improve the contact characteristics, the natural oxide film formed on the semiconductor substrate 1 at the bottom of the connection hole is removed by hydrofluoric acid cleaning, and rinsed with ultrapure water having a low oxygen content to prevent re-oxidation,
Dry with high-purity nitrogen gas purge. An AlTa amorphous thin film 3 was formed on this substrate by a multi-target sputtering apparatus. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ Al-Ta mosaic target Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 400 Å

As a result of the composition analysis, the formed film was Al ₅₅ T
a ₄₅ . The film was amorphous from X-ray diffraction.
In this embodiment, the amorphous thin film 3 is formed by a sputtering method, but a similar amorphous thin film can be formed by a CVD method, a vapor deposition method, or the like. Although an AlTa mosaic target was used in the sputtering of the amorphous thin film 3, Al and Ta were used.
Similarly, an amorphous thin film can be obtained by a method such as a simultaneous sputtering method using a binary target or a method of alternately thinly stacking Al and Ta.

Further, an Al film was formed thereon by sputtering without breaking vacuum. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Al target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar Gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

When the orientation and crystallinity of the thus formed Al film were evaluated by X-ray diffraction, the half value width of the (111) rocking curve was 1.0 °, and good orientation was observed. In this embodiment, the Al film is formed by the sputtering method, but the same effect can be obtained by forming the Al film by the CVD method or the vapor deposition method.

Thereafter, a resist is formed in a desired pattern by a usual lithography technique, and the Al film and the AlTa amorphous thin film 3 are simultaneously dry-etched by using an etching gas containing chlorine, so that the Al film is Processed to. Observation by SEM after processing revealed no residue, and the workability was good. After subjecting this sample to heat treatment at 450 ° C. for 15 minutes in a forming gas (N ₂ : H ₂ = 9: 1), the leak current and contact resistance at the junction were measured. Barrier properties were confirmed.

[0082] The present embodiment will be described with reference to Example 11 FIG 14.

In order to examine the electromigration resistance of the Al metal wiring, an AlTa amorphous thin film and an Al film were formed on a silicon substrate provided with an oxide film under the same conditions as in Example 10, and were used as shown in FIG. An anode 21 as shown in
A test substrate 24 having a cathode 22 and a wiring section 23 having a wiring width of 0.8 μm was prepared by connecting these electrodes. When the orientation and crystallinity of the Al film of this test substrate were evaluated by X-ray diffraction, (1) was obtained in the same manner as in Example 10.
11) The half width of the rocking curve was 1.0 °.

[0084] For this test substrate 24, the test temperature 20
At 0 ° C., a current having a current density of 2 × 10 ⁶ A / cm ² was passed, and the average failure time was measured.
It showed a value of 00 hours or more, indicating high electromigration resistance.

(Example 12) An AlMo amorphous thin film was formed on a substrate on which a functional element was formed in the same manner as in Example 10. As a result of composition analysis, the formed film was Al ₆₀ Mo ₄₀ . The film was amorphous from X-ray diffraction. When the orientation and crystallinity of the Al film formed thereon were evaluated by X-ray diffraction, the half width of the rocking curve of (111) was 1.1 °, and favorable orientation was observed.

Thereafter, a resist is formed in a desired pattern by a usual lithography technique, and the Al film and the Al-Mo amorphous thin film are simultaneously dry-etched by using an etching gas containing chlorine, whereby the Al film is formed by metal wiring. Processed to. Observation by SEM after processing revealed no residue, and the workability was good. After subjecting this sample to a heat treatment at 450 ° C. for 15 minutes in a forming gas (N ₂ : H ₂ = 9: 1), when observing the cross section of the joint, no alloy spike was observed and good barrier properties were confirmed. Was done.

Example 13 An AlNbSi amorphous thin film was formed on a substrate on which a functional element was formed in the same manner as in Example 10. As a result of the composition analysis, the formed film was Al ₄₀ N
b ₅₅ Si ₅ . The film was amorphous from X-ray diffraction. When the orientation and crystallinity of the Al film formed thereon were evaluated by X-ray diffraction, the half width of the (111) rocking curve was 1.3 °, and favorable orientation was observed. Thereafter, a resist was formed in a desired pattern by a usual lithography technique, and the Al film and the AlNbSi amorphous thin film were simultaneously dry-etched using an etching gas containing chlorine, thereby processing the Al film into a metal wiring.
After processing, observation by SEM showed no residue,
Workability was good. After subjecting this sample to a heat treatment at 450 ° C. for 15 minutes in a forming gas (N ₂ : H ₂ = 9: 1), when observing the cross section of the joint, no alloy spike was observed and good barrier properties were observed. confirmed. Also S
By containing i, the thermal stability of the amorphous thin film was improved, and no crystallization or reaction was observed even with a higher temperature heat treatment. This effect was the same for Ge, P, and B.

[0088] The present embodiment will be described with reference to Example 14 Figure 15.

Using a 6-inch silicon wafer substrate 1 having an insulating layer 5 made of a 4000 Å thermal oxide film, a PtZr amorphous thin film 3 was first formed by a multi-target sputtering apparatus shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ PtZr mosaic target Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 500 Å

As a result of the composition analysis, the formed film was Pt ₂₁ Z
r ₇₉ . The film was amorphous by X-ray diffraction measurement.

Next, Pt was sputtered on the PtZr film without breaking the vacuum. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Pt target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 1000 Å

When the orientation and crystallinity of the Pt film 33 thus formed as a lower electrode were evaluated by X-ray diffraction, good crystallinity with a (111) orientation half width of 1.4 ° was observed.

Next, a strontium titanate film 34 was formed as a dielectric thin film on the lower electrode by RF magnetron sputtering. A strontium titanate sintered body was used as a target. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ SrTiO ₃ target Substrate temperature: 500 ° C. Sputtering gas: Ar / O ₂ gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 5000 Å

The orientation and crystallinity of the dielectric thin film obtained by X-ray diffraction were evaluated.
1) The orientation was taken over, and the half-width of the (111) orientation was 1.5 °. An Au film 35 was deposited as an upper electrode on this dielectric thin film, and the characteristics of the capacitor were evaluated. As a result, both the relative dielectric constant and the leakage current were good. On the other hand, the half-width of the orientation of the Pt film directly formed on the thermal oxide film was 9.2 °, and when the strontium titanate film was formed thereon under the same conditions as above, the half-width of the orientation was 9.5 °.

(Embodiment 15) In the same manner as in Embodiment 14, 400
Using a 6-inch silicon wafer substrate provided with a 0 Å thermal oxide film, a Pt ₂₁ Zr ₇₉ film was formed as an amorphous thin film by a multi-target sputtering apparatus.

Next, this amorphous Pt is formed without breaking vacuum.
PtTi as lower electrode by sputtering on ₂₁ Zr ₇₉ film
A film was formed. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Pt / Ti binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 1000 Å

As a result of composition analysis of the PtTi film thus formed, it was Pt ₈₈ Ti ₁₂ . When the orientation and crystallinity were evaluated by X-ray diffraction, the (111) orientation half width was
Good crystallinity of 1.4 ° was observed.

Next, a ferroelectric thin film of lead zirconate titanate was grown on the lower electrode by RF magnetron sputtering. The target used was a powder of lead zirconate titanate with an excess of 10 mol% of lead oxide sintered at 1200 ° C. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ Pb (ZrTi) O ₃ target (PbO 10 mol% RICH) Substrate temperature: 600 ° C. Sputter gas: Ar / O ₂ gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 5000 Angstrom

When the orientation and crystallinity of the ferroelectric thin film obtained by X-ray diffraction were evaluated, (11)
1) The orientation was succeeded, and the half-width at (111) orientation was 1.9 °. On the other hand, the half-width of orientation of the PtTi film directly formed on the thermal oxide film was 9.2 °, and when lead zirconate titanate was formed thereon under the same conditions as above, the half-width of orientation was 9.8 °.

[0100] The present embodiment will be described with reference to Example 16 FIG. 16.

An amorphous AlTa thin film was formed as a resistance heating element film 12 on a glass substrate 1 'by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlTa binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ²

As a result of the composition analysis, the formed film was Al ₂₅ T
a ₇₅ . The film was amorphous according to the X-ray diffraction measurement. An Al thin film was sputtered thereon in the same chamber. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Al target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar Gas pressure: 1 Pa Applied power: 5 W / cm ²

When the crystallinity of the formed Al film was evaluated by X-ray diffraction, it was an oriented film having a (111) rocking curve half width of 1.0 °.

Next, this Al film is processed by lithography and etching steps to form electrodes 13 and 13 ′, and a SiO ₂ insulating film 14 for preventing oxidation and improving abrasion resistance.
Was coated. The thermal head created in this way was actually mounted on a printer and a recording experiment was performed.
Even in a fine pattern, the fluctuation of the recording density was smaller than that in the conventional case. Also, the Al electrode did not deteriorate.

[0105] The present embodiment will be described with reference to Example 17 Figure 17.

An AlNb amorphous thin film was formed as a resistance heating element 12 on a glass substrate 1 'having a projection by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ AlNb binary target Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ²

As a result of the composition analysis, the formed film was Al ₄₀ N
b ₆₀ . The film was amorphous by X-ray diffraction measurement.

The AlNb film was processed by a lithography process and an etching process, and was left only on the convex portion and its periphery. After being transported again into the chamber and subjected to Ar bias cleaning, an Al film was sputtered. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Al target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar Gas pressure: 1 Pa Applied power: 5 W / cm ²

When the crystallinity of the Al film formed on the flat portion was evaluated by X-ray diffraction, it was an oriented film having a (111) rocking curve half-width of 1.2 °.

Next, the Al film was processed by a lithography process and an etching process to obtain electrodes 13 and 13 ′, and a SiO ₂ insulating film 14 was further coated to prevent oxidation and improve abrasion resistance. When a recording experiment was performed under the same conditions as in Example 16, excellent characteristics were shown.

[0111] The present embodiment will be described with reference to Example 18 Figure 18.

Using a 6-inch silicon wafer substrate 1 having an insulating layer 5 made of a 4000 Å thermal oxide film, an AlTa amorphous thin film 3 was first formed by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ AlTa binary target Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 1000 Å

As a result of the composition analysis, the formed film was Al ₄₅ T
a ₅₅ . The film was amorphous by X-ray diffraction measurement.

Next, a groove 38 is formed on the surface of the AlTa amorphous thin film 3 by a usual lithography process and an RIE process.
Was formed. The depth of the groove 38 is 100 angstroms,
The width of the groove 38 was 1000 angstroms.

Next, after performing Al bias cleaning on the AlTa amorphous thin film 3 in which the groove 38 was processed, an Al film was sputtered. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Al target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar Gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

When the orientation and crystallinity of the thus formed Al film were evaluated by X-ray diffraction, it was confirmed that the (111) half-width at orientation was 1.2 ° and good crystallinity was observed.

Further, according to observation by a transmission electron microscope (TEM), as the <211> direction of Al was aligned in the longitudinal direction of the groove 38 formed in the amorphous thin film 3, an Al film having only sub-grain boundaries was obtained. It turned out that it became.

Next, this Al film was processed into a metal wiring 2 and subjected to an EM test. Specifically, a normal lithography step and an RIE step are applied to the Al film to form an anode and a cathode as shown in FIG. 14 and a wiring part having a wiring width of 0.8 μm by connecting these anodes and cathodes. A test board was prepared. Next, the test temperature was set to 200 ° C. and the current density was 2 × 10 ⁶ A for the wiring portion of the test board.
/ Cm ² , but no break occurred after 1000 hours. This indicates that the electromigration resistance was dramatically improved because the Al film was highly oriented and only sub-grain boundaries were formed.

[0119] The present embodiment will be described with reference to (Example 19) Figure 19.

Using a 6-inch silicon wafer substrate 1 having an insulating layer 5 made of a 4000 Å thermal oxide film, grooves were formed by ordinary lithography and RIE processes.

A NiTa amorphous thin film 3 was formed on the substrate 1 by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: NiTa binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 1000 Å

As a result of the composition analysis, the formed film was Ni ₅₀ T
It was a _50. The film was amorphous according to the X-ray diffraction measurement. When the cross section was observed with a scanning electron microscope (SEM), the groove 30 was formed uniformly on the surface of the NiTa amorphous thin film 3, the depth of the groove 30 was 100 Å, and the width of the groove 30 was 1000 Angstrom.

Next, after performing Ar bias cleaning on the NiTa amorphous thin film 3 having the groove 30, the first embodiment is performed.
8, Al was sputtered. When the orientation and crystallinity of the formed Al film were evaluated by X-ray diffraction, (11
1) Good crystallinity with a half value width of 0.9 ° was observed.

Further, according to transmission electron microscope (TEM) observation, the result was that the <211> direction of Al was aligned in the longitudinal direction of the groove 30 formed in the amorphous thin film 3, resulting in an Al film having only sub-grain boundaries. It turned out that it became.

Example 20 A 6-inch silicon wafer substrate provided with a 4000 Å thermal oxide film was used.
An AlNb amorphous thin film was formed by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlNb binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 1000 Å

As a result of the composition analysis, the formed film was Al ₄₀ N
b ₆₀ . The film was amorphous by X-ray diffraction measurement.

Next, a groove was formed in the AlNb amorphous thin film by a usual lithography process and an RIE process. Groove depth 100 Å, film width 10
00 angstrom.

Next, A was added to the AlNb amorphous thin film in which the groove was processed.
After the bias cleaning, A
A 1-0.1 at% Cu alloy was sputtered. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlCu alloy target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

When the orientation and crystallinity of the thus formed AlCu film were evaluated by X-ray diffraction, it was confirmed that the (111) orientation half value width was 0.9 ° and good crystallinity was observed. When this film is subjected to heat treatment at 450 ° C. for 30 minutes, (111)
The orientation was further improved, and the (111) orientation half width was 0.7 °.

According to transmission electron microscope (TEM) observation, the <211> direction of Al was aligned with the longitudinal direction of the groove formed in the amorphous thin film, and as a result, Al having only sub-grain boundaries was obtained.
It turned out that it was a Cu film. In addition, a metal wiring was formed under the same conditions as in Example 18 and an EM test was performed.
No wiring breakage occurred even after lapse of 000 hours.

[0131] (Example 21) The present embodiment will be described with reference to FIG. 20, 22.

Thermal oxidation on Si (100) 6 inch substrate 1
After forming the film as an insulating layer 5 at 1000 Å,
The following seven samples were prepared. That is, No. 1 is perfect
Amorphous SiO as edge layer 5_Two (Surface energy: 605e
rg / cm^TwoLithography process and RIE process
Depending on the process, L / S (0.3 / 0.3 μm) and groove depth 20
The surface was machined to 0 Å (FIG.
(A)). L / S isFIG.Shown in No. 2 is thermal oxidation
Polycrystalline Ta (surface energy: 2150 erg / cm)^Two)
Sputter to form a 500 Å Ta film 39
And then amorphous SiO_Two 200 Angstroms
Strom's SiO_Two After forming the film 43, the SiO_TwoMembrane 43
With L / S (0.3 / 0.3μm) and groove depth 200 on
Processed into gustrom (FIG.(B)). No. 3
Is to sputter polycrystalline Ta on the thermal oxide film and
After forming the storm Ta film 39, the Ta film 39 is
(0.3 / 0.3μm) and groove depth 200 Å
Processed into aFIG.(C)). No. 4 is thermal oxidation
Amorphous Ni on film₆₂Nb₃₈(Surface energy: 1326erg /
cm ^Two) To 200 Å of NiNb
After forming the film 40, the NiNb40 film is changed to L / S (0.3 /
(0.3μm) with groove depth of 200 Å
did(FIG.(D)). No. 5 is amorphous on thermal oxide film
Quality Ta-60 at% Al (Surface energy: 1640 erg / cm
 2) Sputtered to 200 Å TaAl film
After the formation of the TaAl film 41, the TaAl film 41 is formed into an L / S (0.3 / 0.
3 μm) and processed to a groove depth of 200 Å
(FIG.(E)). No. 6 shows an amorphous T on the thermal oxide film.
a-60 at% Al sputtered to 100 Å
A TaAl film 41 is formed, and an amorphous SiO_Two 
Sputtered to 100 Å of SiO_Two Membrane 43
After forming, SiO_Two The film 43 and the TaAl film 41 are
S (0.3 / 0.3μm), groove depth 200 angst
Processed into loam (FIG.(F)). No. 7 is hot acid
200 angstroms of polycrystalline Si (surface
Energy: 730erg / cm^Two) Is deposited, and the resulting Si film 4
2 with L / S (o. 3 / 0.3 μm) and groove depth 200
Processed into ngstrom (FIG.(G)). Over it
The cross section of each final shapeFIG.Shown in Then,
Of pure Al on a substrate of 200.degree.
After depositing 00 angstrom, it is processed into a four-terminal shape.
An EM test was performed. Measurement part wiring width is 1μm, length 2
000 μm. The test conditions were 150 ° C and 1 ×
It was 107 A / cm2. Table 5 shows the results.

[Table 5]

(Example 22) After forming a thermal oxide film on a 6 inch Si (100) substrate at a thickness of 1000 angstroms,
a-40 at% Al was sputtered to form a 200 angstrom film, and each of the L / Ss shown in Table 6 was processed by RIE to form grooves. For these, the ultimate vacuum 10
After removing the surface oxide film on the surface of the AlTa film by Ar plasma etching in a high vacuum sputter of the order of -10 torr, pure Al was continuously formed in a thickness of 4000 Å. After this E
The M test was performed as in Example 21. Table 6 shows the results.

[Table 6]

[0134] The present embodiment will be described with reference to Example 23 Figure 22.

Using a 6-inch silicon wafer substrate 1 having an insulating layer 5 made of a 4000 Å thermal oxide film ( FIG. 22A ), a normal lithography process and RI
A groove 36 was formed in the E step ( FIG. 22B ). The depth of the groove 36 is 100 angstroms, and the width of the groove 36 is 1
The thickness was set to 500 angstroms.

On this, an AlTa amorphous thin film 3 was formed by a multi-target sputtering apparatus as shown in FIG. 4 ( FIG . 22C). The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ AlTa binary target Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 1000 Å

As a result of the composition analysis, the formed film was Al ₇₅ T
a ₂₅ . The film was amorphous according to the X-ray diffraction measurement. Subsequently, when the substrate 1 was heated at 450 ° C. for 30 minutes,
The AlTa amorphous thin film 3 crystallized to form an intermetallic compound of Al ₃ Ta, and became a polycrystalline film 37 having a grain size of 1 to 2 μm and having sub-grain boundaries ( FIG . 22D). An Al film as the metal wiring 2 was sputtered thereon in the same chamber ( FIG.
22 (e)). The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: Al target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar Gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

When the orientation and crystallinity of the formed Al film were evaluated by X-ray diffraction, the (111) orientation half width was improved to 0.3 °, and most of the crystal grain boundaries remaining in the Al film were subgrains. Was the world.

Next, an EM test was performed on the metal wiring 2 made of this Al film. More specifically, an anode and a cathode as shown in FIG. 14 were prepared by processing the Al film by a normal lithography process and an RIE process, and a wiring portion having a wiring width of 0.8 μm by connecting these was formed. The test board provided was used. A test was conducted at a test temperature of 200 ° C. and a current corresponding to a current density of 2 × 10 ⁶ A / cm ² was passed through the wiring portion of the test board. However, no break occurred even after 1000 hours. This indicates that the electromigration resistance has been dramatically improved because the crystallinity of the Al film is close to that of a single crystal.

(Example 24) A 6-inch silicon wafer substrate provided with a 4000 Å thermal oxide film was used.
A groove was formed by a normal lithography process and an RIE process. The depth of the groove is 500 angstroms, the width of the groove is 5000 angstroms, and the distance between the grooves is 3000
Angstrom.

An AlNb amorphous thin film was formed on this substrate by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlNb binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 400 Å

As a result of the composition analysis, the formed film was Al ₇₅ N
b ₂₅ . The film was amorphous by X-ray diffraction measurement. Subsequently, when the substrate was heated at 450 ° C. for 30 minutes, the AlNb amorphous thin film was crystallized to form an intermetallic compound of Al ₃ Nb and was buried in the groove to become a single crystal. Thereafter, the substrate surface was flattened by polishing. Subsequently, the wafer is again transported into the chamber and subjected to Ar bias cleaning.
At% Cu alloy was sputtered. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlCu alloy target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

The thus formed AlCu film was processed by an RIE process to form a metal wiring, and an EM test was performed under the same conditions as in Example 23. As a result, no wiring breakage occurred even after 1000 hours.

[0144] The present embodiment will be described with reference to (Example 25) Figure 23.

As shown in FIG . 23 , a pure Al thin film to be a metal wiring 2 was formed on a Si wafer substrate 1 on which a thermal oxide film was formed as an insulating layer 5 by 1000 angstroms by 4000 angstroms sputtering. After forming this Al thin film, the thickness of the AlTa amorphous thin film 3 is continuously reduced to 10
What changed to 0, 300, 500 angstroms,
Each was formed by sputtering using a target composed of a mosaic of Al and Ta, and was taken out. In addition, after forming an Al thin film on some of the samples, the sample was once exposed to the atmosphere, and the wafer was guided again into the sputtering apparatus, and the AlTa amorphous thin film 3 was converted into pure A.
1 formed on the thin film. At this time, the sample exposed to the air was subjected to RF using the substrate 1 as an electrode before forming the amorphous thin film 3.
Surface oxide was removed by -Ar plasma. However, when removing the surface oxide, RHEED was used to remove A
Plasma etching was performed until a clear diffraction pattern of the thin film was observed. The composition of the amorphous thin film 3 is Al ₂₀
Ta ₈₀ .

In order to examine the frequency of occurrence of hillocks in the metal wiring 2 with respect to the laminated structure of the metal wiring 2 and the AlTa amorphous thin film 3 made of the pure Al thin film formed in this manner, 450 samples of these thin film samples were used. A heat treatment at 30 DEG C. for 30 minutes was performed in a forming gas (N2-H2). Table 7 shows hillock densities measured using an optical microscope and a stylus-type film thickness meter. As shown in Table 7, it was found that the presence of the amorphous thin film 3 significantly reduced the number of hillocks and maintained this effect even when the thickness of the amorphous thin film 3 was 100 Å.

[Table 7]

Example 26 One thermal oxide film was used as an insulating layer.
On a Si wafer substrate formed with 2,000 Å,
A pure Cu thin film serving as a metal wiring was formed by 4000 angstrom sputtering. After this Cu thin film is formed, the CuZr amorphous thin film is continuously 100, 300, and 500 Å, or the NiNb amorphous thin film is 100,
It was formed by 300, 500 angstroms binary sputter deposition. In addition, some of the samples were exposed to the atmosphere once after forming a Cu thin film, and the wafer was guided again into the sputtering apparatus,
A uZr or NiNb amorphous thin film was formed on a pure Cu thin film. At this time, the surface oxide of the sample exposed to the atmosphere was removed by RF-Ar plasma using the substrate as an electrode before forming the amorphous thin film. However, in removing the surface oxide, plasma etching was performed by RHEED until a clear diffraction pattern of the Cu thin film was observed. The composition of the amorphous thin film is Cu ₅₀ Zr ₅₀ or N
i ₆₅ Nb ₃₅ .

In order to examine the oxidation resistance of the thin film of the metal wiring formed of the pure Cu thin film and the laminated structure of the CuZr or NiNb amorphous thin film formed as described above, these thin film samples were subjected to 500 ° C. for 30 minutes. Was performed in the air. Here, Cu and Ni are in a solid solution in all ratios.
Table 8 shows the results. As shown in Table 8, the pure Cu thin film has significant irregularities on the thin film surface due to volume expansion accompanying the progress of oxidation, whereas the CuZr or NiNb amorphous thin film is laminated with a stylus type thin film. As shown in Table 8, no significant difference occurred in the evaluation of the surface roughness using the meter.

[Table 8]

[0149] The present embodiment will be described with reference to Example 27 Figure 24.

Using a 6-inch silicon wafer substrate 1 having an insulating layer 5 made of a 4000 Å thermal oxide film, first, Sn was deposited on a one atomic layer (ML) substrate, and Sn was deposited.
Film 51 was deposited. The K cell temperature at this time is 1100
° C and the substrate temperature is 450 ° C. Then, an Al film as a metal wiring 2 was deposited on the substrate 1 on which the Sn film 51 was deposited without breaking the vacuum by 1000 angstroms. At this time, the K cell temperature is 1050 ° C., and the substrate temperature is room temperature.

When the orientation of the thus formed Al film was evaluated by X-ray diffraction, good crystallinity having a (111) orientation half width of 2.0 ° was observed.

In addition to Sn, Ga, In, Cd, Bi, P
Similar results were obtained for b and Tl.

Example 28 Using a 6-inch silicon wafer substrate having an insulating layer composed of a 4000 Å thermal oxide film, first, Pb was vapor-deposited on a 1 atomic layer substrate. The deposition conditions are a K cell temperature of 600 ° C. and a substrate temperature of room temperature. Next, a 1000 Å Cu film was deposited on the substrate on which Pb was deposited without breaking vacuum. At this time, the K cell temperature is 1200 ° C., and the substrate temperature is room temperature.

When the orientation of the thus formed Cu film was evaluated by X-ray diffraction, good crystallinity with a (111) orientation half width of 4.0 ° was observed.

Similar results were obtained for Tl in addition to Pb.

(Example 29) A 6-inch silicon wafer substrate having an insulating layer made of a 4000 Å thermal oxide film was used and a multi-target sputtering apparatus was used.
An lTa amorphous thin film layer was formed. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ AlTa mosaic target Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 0.20 Pa Film thickness: 400 Å

As a result of the composition analysis, the formed film was Al ₅₅ T
a ₄₅ . The film was amorphous from X-ray diffraction.

[0158] Next, Sn was applied on this without breaking vacuum.
Was deposited in one atomic layer. The deposition conditions are the same as in Example 27. Further, an Al film was deposited on the substrate on which Sn was deposited without breaking vacuum by 1,000 angstroms. At this time, the K cell temperature is 1050 ° C., and the substrate temperature is room temperature.

The orientation of the thus formed Al film was evaluated by X-ray diffraction. As a result, good crystallinity with a (111) orientation half width of 1.6 ° was observed.

Example 30 A (111) 5-inch silicon wafer substrate having an insulating layer made of a thermal oxide film was used.
0.5 and 1 atomic layer (ML) of Bi were deposited, respectively.
At this time, the K cell temperature is 600 ° C., and the substrate temperature is room temperature. Next, 100 Å of an Al film was deposited on each of the substrates on which Bi was deposited without breaking the vacuum. At this time, the K cell temperature is 1050 ° C., and the substrate temperature is room temperature. For comparison, a sample in which an Al film was immediately deposited on a substrate was also prepared.

The Al film thus formed was subjected to RHEE
The orientation and crystallinity were evaluated by D and X-ray diffraction. FIG. 25 shows RHEED photographs of these samples. In the sample in which Bi was not deposited, as shown in FIG. 25 (a), R (111) and (100) orientations were mixed.
HEED pattern was obtained. On the other hand, in the sample in which Bi was deposited by one atomic layer, as shown in FIG.
0) No orientation was observed, and a good crystal having a (111) orientation half width of 0.3 ° was obtained. In the sample on which 0.5 atomic layer of Bi was deposited, the half width at (111) orientation was 0.5 °, but the (100) orientation was not observed. In addition, when the surface shape of the Al film was observed using SEM, it was confirmed that the sample on which Bi was deposited had high surface smoothness.

When the composition of the Al film was analyzed using AES, it was found that Bi existed on the surface of the Al film, the grain boundary of the Al film, and the interface between the Al film and the thermal oxide film.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

(Example 31) First, one atomic layer of Bi was vapor-deposited using a 6-inch silicon wafer substrate having an insulating layer made of a thermal oxide film of 4000 angstroms. At this time, the K cell temperature is 600 ° C., and the substrate temperature is room temperature. Next, 500 Å of an Al film was deposited on each of the substrates on which Bi was deposited without breaking vacuum. At this time, the K cell temperature is 1050 ° C., and the substrate temperature is room temperature. For comparison, a sample was prepared by immediately depositing an Al film on a substrate.

Observation of the obtained Al film using an SEM revealed that the crystal grain size of the sample on which Bi was deposited was 1890
While the grain has grown to ± 20 angstroms,
In the sample in which Bi was not deposited, the crystal grain size was 980 ± 2.
It was 0 angstroms. The composition of the Al film was analyzed using AES.
It was found that the film was present at the grain boundary of the l film and at the interface between the Al film and the thermal oxide film.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

Example 32 Using a 6-inch silicon wafer substrate having an insulating layer made of a 4000 Å thermal oxide film, Bi was deposited on a monoatomic layer substrate. The deposition conditions are the same as in Example 31. Next, 500 Å of an Al film was deposited on the substrate on which Bi was deposited without breaking the vacuum. The K cell temperature at this time is 1050
° C and the substrate temperature is 400 ° C. For comparison, a sample was prepared by immediately depositing an Al film on the substrate.

When the obtained Al film was observed by using an SEM, the crystal grain size was 3130 in the sample on which Bi was deposited.
While the grain has grown to ± 20 angstroms,
In the sample in which Bi was not deposited, the crystal grain size was 1230 ±
It was 15 angstroms.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

Example 33 Using a 6-inch silicon wafer substrate having an insulating layer made of a 4000 Å thermal oxide film, an AlTa amorphous thin film layer was first formed by a multi-target sputtering apparatus. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ AlTa mosaic target Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar gas pressure: 0.20 Pa Film thickness: 400 Å

As a result of the composition analysis, the formed film was Al ₅₅ T
a ₄₅ . The film was amorphous from X-ray diffraction.

Next, Bi is applied on this without breaking vacuum.
Was deposited in one atomic layer. The deposition conditions are the same as in Example 31. Further, without breaking the vacuum, an Al film was vapor-deposited on the substrate on which Bi was vapor-deposited by 500 Å. At this time, the K cell temperature is 1050 ° C., and the substrate temperature is room temperature. For comparison, a sample was prepared by immediately depositing an Al film on the AlTa amorphous thin film layer.

Observation of the obtained Al film using an SEM revealed that the crystal grain size of the Bi-deposited sample was 2970
While the grain has grown to ± 20 angstroms,
In the sample in which Bi was not deposited, the crystal grain size was 960 ± 1.
It was 0 angstroms.

EXAMPLE 34 A (111) -oriented Al film was formed on a high-resistance (111) silicon wafer substrate by high vacuum sputtering at 4000 Å. As a pre-treatment at this time, after the treatment with 1% HF, washing with water was performed by cutting off the atmosphere with ultrapure water having a dissolved oxygen of 5 ppb. Then, width 0.5
A four-terminal pattern having a size of μm and a length of a measuring portion of 1000 μm was formed to form a metal wiring. Then under 150 ℃ environment
After energizing at the five types of current densities shown in Table 9 , N
₂ : 400 ° C., 3 in H ₂ = 8: 2 forming gas
A heat treatment for 0 minutes was performed. Thereafter, the presence or absence of pits (Si spikes) in the wiring was examined by SEM. Also, L
Table 9 also shows the results of examining the Al (111) orientation half-width by X-rays after preparing a wiring pattern having a / S of 1 μm / 1 μm and performing the same processing.

[Table 9]

[0175] The present embodiment will be described with reference to Example 35 Figure 26.

After forming an SiO ₂ thermal oxide film as an insulating layer 5 on the Si (100) substrate 1 by 1000 angstroms,
AlTa film 5 having a composition of Al ₃₀ Ta ₇₀ as an amorphous thin film
2 was formed by 300 angstrom dual simultaneous sputtering. L / S is 1500 angstrom / 1500 angstrom and depth 30 by lithography after film formation
A groove 54 of 0 Å was formed. Furthermore, 1 ×
Evacuate to a vacuum of 10 ^-8 torr or less, and set the substrate bias voltage to
The oxide film on the AlTa film 52 was removed by exposing to plasma for 5 minutes by bias cleaning with applied 0 V, and then an Al film was formed to 4000 angstroms. On the other hand as a comparative material, directly Al film on SiO ₂ 4
A film having a thickness of 000 angstroms was prepared. Next, these Al films were formed to have a width of 0.5 μm and a length of the measurement portion of 1 μm.
The metal wiring 2 is formed by processing into a four-terminal pattern of 000 μm, and a current of 1 × 10 ⁷ A / cm ² is applied in a 200 ° C. environment
After energization for the time shown in Table 10 , heat treatment was performed at 400 ° C. for 30 minutes in a forming gas of N ₂ : H ₂ = 8: 2. Thereafter, the presence or absence of hillocks in the wiring was examined by SEM. Table 10 shows the results.

The L / S of each of these samples was 1
After forming a wiring pattern of μm / 1 μm and performing the same processing, the results of examining the Al (111) orientation half-value width by X-ray are also shown in Table 10 .

[Table 10]

( Example 36 ) After forming a thermal oxide film as an insulating layer on a (100) Si substrate at 1000 Å,
The TiN film is formed as the compound layer, 600 an N ₂ atmosphere
The heat treatment of ° C was performed. Subsequently, various bias voltages shown in Table 11 were applied to the substrate in a plasma of Ar: N ₂ = 1: 1 and gas pressure of 1 × 10 ⁻³ Torr, and the TiN film was sputter-etched. After that, the Al film is sputtered to 4000
Angstrom was formed. This Al film is 0.5 μm
An EM test was performed by forming a metal wiring by processing into a four-terminal pattern having a width of 1 mm. The test condition is a wiring temperature of 200
° C and the current density is 2 × 10 ⁶ A / cm ² . Table 1 shows the results
It is shown in FIG. Also, for comparison, the TiN film was not subjected to sputter etching,
Table 11 also shows the results of exposure to the _two plasmas.

[Table 11]

( Example 37 ) After forming an SiO ₂ thermal oxide film as an insulating layer on a 6 inch substrate of Si (100) at 1000 Å, an amorphous thin film having a composition shown in Table 12 was sputtered using a mosaic target. Alternatively, a film was formed by simultaneous sputtering using a multi-target, and then a Cu film was formed in a thickness of 4000 Å. At this time, since the various amorphous thin films to be the base are once exposed to the atmosphere, the surface of the amorphous thin film is cleaned by sputter etching before forming the Cu film in order to remove the oxide film on the surface. did. Surface cleaning conditions are A
r gas pressure: 1.0 × 10 ⁻³ Torr, RF output at 100 MHz: 100 W, substrate bias voltage: −50 V, cleaning time: 4 minutes.

The crystallinity of the underlayer was confirmed each time by RHEED, and it was confirmed that the underlayer was an amorphous thin film.

The Cu film was formed by 1 × 1 after surface cleaning.
It is performed under the condition that the vacuum does not deteriorate to 0 ^-8 Torr or more.
The gas pressure was 1.0 × 10 ⁻³ Torr, the RF output at 100 MHz was 400 W, the cathode bias voltage was −300 V, and the deposition rate was 40 Å / sec.

After the film formation, the crystallinity of the Cu film was evaluated by X-rays.
Further, in order to evaluate the electromigration resistance, the wiring was processed into a four-terminal pattern having a wiring width of 1 μm and a wiring length of 300 μm to form a metal wiring.
An energization test was performed under the conditions of a temperature of 2 ° C. and a current density of 2 × 10 ⁶ A / cm ² . The above results are also shown in Table 12 .

[0183] Further, also evaluated in the same manner that was deposited directly Cu film on SiO ₂ thermal oxide film as a comparative example, shown in Table 12.

If the base is amorphous, the same result can be obtained even if the composition is shifted from that shown in Table 12 . Also, a small amount of additives may be added for the purpose of improving corrosion resistance, workability, barrier properties, and the like.

When the amorphous thin film is kept at a vacuum of 1 × 10 ⁻⁸ Torr or less after the film is formed, and then the Cu film is continuously formed, the surface cleaning is not particularly required.

[Table 12]

[0186] The present embodiment will be described with reference to Example 38 Figure 27.

An amorphous thin film of TiNb, TiTa, ZrNb, ZrTa, T was formed on a Si substrate 1 on which an insulating layer 5 made of a thermal oxide film was formed in a thickness of 1000 angstroms by a multiple simultaneous sputtering method using Ar gas.
iW, ZrMo, TiY, ZrY alloy thin film 56
0 angstrom was formed. At this time, the composition of the alloy thin film 56 is Ti ₅₀ Nb ₅₀ , Ti ₅₀ Ta ₅₀ , and Zr ₅₀ Nb, respectively.
_{50, Zr 50 Ta 50, Ti} 50 W 50, Zr 50 Mo 50, Ti 50
Y _50, Zr ₅₀ Y such that ₅₀ was adjusted power applied to each target. While continuing to maintain the vacuum,
The gas was replaced with nitrogen gas, and the surface of the alloy thin film 56 was exposed to nitrogen plasma by RF discharge using the substrate 1 as an electrode.
After that, the crystallinity of the alloy thin film 56 was evaluated by RHEED. As a result, it was confirmed that the surface of the alloy thin film 56 was amorphous even after being exposed to nitrogen plasma. The surface of No. 56 contained nitrogen element, and it was presumed that a surface layer made of amorphous nitride was formed in the alloy thin film 56. For comparison, a sample not subjected to the nitrogen plasma treatment was also prepared.

Next, the alloy thin film 56 thus formed is formed.
Was once exposed to the atmosphere, and a metal wiring 2 made of a pure Al or pure Cu thin film was formed on the alloy thin film 56 at 4000 Å by a sputtering method. At this time, the metal wiring 2
Before the formation of the alloy thin film 5,
6 were prepared with and without surface etching. Then, the obtained pure Al thin film or pure C
The crystal orientation of the u thin film was evaluated by measuring the half width of the (111) rocking curve of Al and Cu by X-ray diffraction using CuKα radiation. Table 13 shows the results. As a result, even when the alloy thin film 56 is exposed to the atmosphere on the alloy thin film 56 subjected to the nitrogen plasma treatment, pure Al having a high (111) crystal orientation can be obtained without etching the surface by Ar plasma in advance. Or it turned out that the metal wiring 2 of a pure Cu thin film was formed.

[Table 13]

Example 39 A carbide alloy thin film shown in Table 14 was formed on a Si substrate on which an insulating layer made of a thermal oxide film was formed to a thickness of 1000 angstroms by a multiple simultaneous Ar sputtering method using a metal target and a carbon target. 100 angstrom was formed. At this time, the power supplied to each target was adjusted so that the carbide alloy thin films had the compositions shown in Table 14 , respectively. When the crystallinity of the thin film surface after film formation was evaluated by RHEED, a halo pattern peculiar to amorphous was obtained. Next, after the carbide alloy thin film as an amorphous thin film thus formed is once exposed to the atmosphere, pure Al or pure C is formed by sputtering.
4000 angstrom metal wiring made of u thin film,
It was formed on a carbide alloy thin film. At this time, before the metal wiring was formed, the one where the surface of the underlying carbide alloy thin film was etched with Ar plasma and the one where the surface was not applied were prepared. Next, the crystal orientation of the obtained pure Al thin film or pure Cu thin film was evaluated by measuring the half width of the (111) rocking curve of Al and Cu by X-ray diffraction using CuKα radiation. Table 14 shows the results. As a result, a metal wiring of a pure Al or pure Cu thin film having a high (111) crystal orientation is formed on these carbide alloy thin films without exposing the surface by Ar plasma in advance even when exposed to the air. I found out.

[Table 14]

Example 40 A 6-inch silicon wafer provided with a 1000 Å thermal oxide film was used as a substrate, and Bi was deposited on the substrate. The deposition conditions were Example 3.
Same as 1. Then, an Al film was formed on the substrate on which Bi was deposited without breaking the vacuum by 200 Å to 10 Å.
00 Å was deposited. At this time, the K cell temperature is 1200 ° C., and the substrate temperature is room temperature. For comparison, a sample was prepared by immediately depositing an Al film on a substrate.
After the formation of the Al film, the substrate temperature was raised to 400 ° C., and heat treatment was performed for 3 hours.

The surface shape of the deposited Al film was determined by SEM and T
Observation using EM revealed that the particle size of the Al film in the presence of Bi was 7810 ± 30 Å, and the particle size of the Al film in the absence of Bi was 1680 ± 20 Å. In other words, the Al film with Bi
It was confirmed that the grain size was larger than that of the Al film in the case where there was no.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

Example 41 A 6-inch silicon wafer provided with a 1000 Å thermal oxide film was used as a substrate, and 200 Å to 1000 Å of Al and Bi1ML were simultaneously vapor-deposited on the substrate at the initial stage of Al deposition while rotating the substrate. did. The deposition conditions for Bi are the same as those in Example 31, the K cell temperature for Al deposition is 1200 ° C., and the substrate temperature is room temperature. For comparison,
A sample was prepared by depositing only Al on the substrate under the same conditions without supplying Bi.

The surface shape of the deposited Al film was determined by SEM and T
Observation using EM revealed that the particle size of the Al film in the presence of Bi was 4370 ± 20 Å, and the particle size of the Al film in the absence of Bi was 1170 ± 15 Å. In other words, the Al film with Bi
It was confirmed that the grain size was larger than that of the Al film in the case where there was no. FIGS. 28A and 28B show SEM photographs of these samples. FIG. 28A is a surface SEM photograph of a sample in which 500 Å of Al is formed on the thermal oxide film, and FIG.
5 is a surface SEM photograph of a sample on which 500 Å and Bi of 1 ML were simultaneously formed. The same effect was obtained even when Bi was deposited during the middle stage of Al deposition or before the end of deposition.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

Example 42 A 6-inch silicon wafer provided with a 1000 Å thermal oxide film was used as a substrate, and Al crystal grains having a (111) orientation with respect to the substrate were formed on the substrate using a thermal CVD apparatus. Grew. The conditions are as follows. Source gas: Triisobutylaluminum Source gas supply method: Bubbling method using Ar Substrate temperature: 400 ° C. Ar gas flow rate: 20 sccm

The density of Al crystal grains obtained under these conditions was 5 × 10 ⁷ to 1 × 10 ⁸ / cm ² .

On this, Bi was deposited under the same conditions as in Example 31. Next, Al was vapor-deposited on the substrate on which Bi was vapor-deposited in a thickness of 200 Å to 1000 Å without breaking vacuum. The K cell temperature is 1200 ° C. and the substrate temperature is room temperature. For comparison, a sample was prepared in which an Al film was immediately deposited without depositing Bi.

The surface shape of the deposited Al film was determined by SEM and T
Observation using EM revealed that the particle size of the Al film with Bi was 3610 ± 15 Å, and the particle size of the Al film without Bi was 1140 ± 20 Å. In other words, the Al film with Bi
It was confirmed that the grain size was larger than that of the Al film in the case where there was no. When the crystallinity of the Al film thus formed was evaluated by X-ray diffraction, the half value width of the (111) rocking curve was 1.0 °. On the other hand, when Bi and Al are evaporated under the same conditions on a substrate on which no Al crystal grains are grown, the half width is 2.0 °, and the crystallinity of the Al film is improved by the presence of the Al crystal grains. Became clear.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

[0201] The present embodiment will be described with reference to Example 43 Figure 29.

A groove as shown in FIG. 29A was formed on the surface of the insulating layer 5 of the 6-inch silicon wafer substrate 1 provided with the insulating layer 5 made of a 4000 Å thermal oxide film. Next, 200 Å of Al was deposited on the substrate. The K cell temperature of Al deposition is 1200 ° C., and the substrate temperature is room temperature. The surface and cross-sectional shape of the obtained Al film are S
Observation using EM showed that Al20 was uniformly deposited on both the groove portion and the surface of the thermal oxide film other than the groove, as shown in FIG. 29 (b).

On the same grooved substrate, an Al film was deposited by 200 Å under the same conditions as described above. The substrate temperature is room temperature. 400 without breaking vacuum
C. for 3 hours. When the surface and cross-sectional shape of the Al film after the heat treatment were observed using an SEM, FIG.
As shown in (c), it was confirmed that the groove portion of the substrate was almost completely buried by the metal wiring 2 made of Al, while Al20 was hardly deposited on the surface of the thermal oxide film other than the groove. Was.

Next, on a similar grooved substrate, Al200
Angstrom and Bi1ML were co-evaporated early in the Al deposition. The conditions for depositing Bi are the same as those in Example 31, and the conditions for depositing Al are as described above. The substrate temperature is also room temperature. The surface of the Al film thus created,
When the cross-sectional shape was observed using an SEM, FIG.
As shown in (d), it was confirmed that the groove was almost completely buried by the metal wiring 2 made of Al, while Al20 was hardly deposited on the surface of the thermal oxide film other than the groove. In other words, although the film was formed immediately at room temperature, the same effect as in the case of heat treatment after film formation was obtained due to the presence of Bi.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

Example 44 Using a 6-inch silicon wafer provided with a 4000 Å thermal oxide film as a substrate, an AlTa amorphous thin film was formed by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlTa binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 50 Å

As a result of the composition analysis, the formed film was Al ₂₅ T
a ₇₅ . The film was amorphous by X-ray diffraction measurement.

An Al thin film was sputtered on this AlTa amorphous thin film. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ Al target Substrate temperature: room temperature (25 ° C.) Sputtering gas: Ar Gas pressure: 1 Pa Applied power: 5 W / cm ² Film thickness: 4000 Å

When the orientation of the thus formed Al film was evaluated by X-ray diffraction, the half width of the rocking curve of the Al (111) peak was (111) oriented film having a half value width of 1.0 °. Then, when the thin film was subjected to a heat treatment at 300 ° C. for 15 minutes, the half width was improved to 0.8 °. 5 more
When heat treatment was performed at 00 ° C. for 15 minutes, the amorphous thin film reacted with the Al thin film to form an Al 3 Ta phase, and the amorphous thin film disappeared. However, the specific resistance did not increase in the reactive thin film, and the orientation further improved to 0.6 °, indicating that a highly oriented thin film was formed on the thermal oxide film.

Next, this highly oriented thin film was processed into a metal wiring, and an EM test was performed. More specifically, a normal lithography process and an RIE process are applied to the highly oriented thin film to connect an anode and a cathode as shown in FIG. 14 and a wiring portion having a wiring width of 0.8 μm. A test substrate provided with was prepared. Next, the test temperature was set to 200 ° C. and the current density was 2 × 10 ⁶ A for the wiring portion of the test board.
/ Cm ² , but no break occurred after 1000 hours. This indicates that the (111) orientation of the Al thin film was improved by the heat treatment, so that the electromigration resistance was dramatically improved.

Example 45 Using a 6-inch silicon wafer provided with a 4000 Å thermal oxide film as a substrate, an AlNb amorphous thin film was formed by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlNb binary target of 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm 2 Film thickness: 500 Å

As a result of the composition analysis, the formed film was Al ₇₅ N
b ₂₅ . The film was amorphous by X-ray diffraction measurement. An Al thin film was sputtered on this AlNb amorphous thin film under the same conditions as in Example 44 . Al thus created
When the orientation of the film was evaluated by X-ray diffraction, it was a (111) oriented film having a rocking curve with a half width of 1.5 °. Further, when the thin film 12 was subjected to a heat treatment at 400 ° C. for 15 minutes, the amorphous thin film was crystallized and disappeared, and the half width of the Al thin film was improved to 0.9 °. Also implemented
An EM test was performed after forming a metal wiring in exactly the same manner as in Example 44. As a result , no break occurred even after 1000 hours.

Example 46 Using a 6-inch silicon wafer provided with a 4000 Å thermal oxide film as a substrate, a CuTi amorphous thin film was formed by a multi-target sputtering apparatus as shown in FIG . The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ CuTi binary target Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 500 Å

As a result of the composition analysis, the formed film was Cu ₅₀ T
i ₅₀ . The film was amorphous by X-ray diffraction measurement. After this CuTi amorphous thin film is once exposed to the atmosphere, it is cleaned by Ar plasma to remove AlCu.
An alloy thin film was sputtered. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: 100 mmφ AlCu alloy target (C
substrate temperature: room temperature (25 ° C.) sputtering gas: Ar gas pressure: 1 Pa applied power: 5 W / cm ² film thickness: 4000 angstrom

When the orientation of the thus formed AlCu film was evaluated by X-ray diffraction, it was a (111) oriented film having a rocking curve half width of 0.9 °. When the thin film was subjected to a heat treatment at 400 ° C. for 15 minutes, the amorphous thin film was crystallized and disappeared, and the (111) orientation of the AlCu film was further improved, and the half width became 0.6 °.

Example 47 A TiN / Ti layer was formed as a diffusion preventing layer on a 6-inch silicon wafer substrate, and an AlTa amorphous thin film was formed thereon by sputtering. The sputtering conditions are shown below. Sputtering method: RF magnetron method Target: AlTa binary target with 100 mmφ Substrate temperature: room temperature (25 ° C.) Sputter gas: Ar gas pressure: 0.20 Pa Applied power: 10 W / cm ² Film thickness: 100 Å

As a result of the composition analysis, the film formed was Al ₄₀ T
a ₆₀ . The film was amorphous by X-ray diffraction measurement. An Al thin film was sputtered on this AlTa amorphous thin film under the same conditions as in Example 44 . Al thus created
When the orientation of the film was evaluated by X-ray diffraction, it was a (111) oriented film having a rocking curve half width of 1.3 °. Further, when heat treatment was performed at 500 ° C. for 15 minutes, the amorphous thin film and the Al thin film reacted to form an Al ₃ Ta phase, and the amorphous thin film disappeared. However, in the thin film after the reaction, the specific resistance did not increase, the orientation was improved to 0.8 °, and it was found that the reaction with silicon was suppressed by the TiN / Ti layer. After forming a metal wiring exactly as in Example 44 , an EM test was performed.
No break occurred after 0 hours.

[0218] (Example 48) with a 4000 Å thermal oxide film 6-inch silicon wafer substrate, FIG.
Using a multi-target sputtering apparatus as shown in FIG. 4 , the power supplied to the Al and V, Nb, Ta, Mo, and W targets was adjusted, and V _x Al _{100-x having the} compositions shown in Tables 15 to 19 , respectively. _{, Nb x Al 100-x,} Ta x Al
_100-x , Mo _x Al _100-x , W _x Al _100-x
Angstrom, sputtered. At this time, it was confirmed by X-ray diffraction that an amorphous thin film was formed in each sample. As shown in Tables 15 to 19 , V,
A halo peak peculiar to amorphous was not observed in a region where the atomic concentration of Nb, Ta, Mo, and W was extremely high or low. Next, these samples were again introduced into the sputtering apparatus, and after cleaning with Ar plasma, a pure Al film was deposited to 4000 Å. At this time, the (111) orientation half width of the deposited Al thin film was evaluated by X-ray, and the (111) orientation controllability of the amorphous thin film was confirmed. The results are shown in Tables 15 to 19 .

Subsequently, these thin films were processed into an electromigration (EM) accelerated test pattern having a wiring width of 0.8 μm as shown in FIG. 14 by ordinary PEP and RIE processes to form metal wirings. Thereafter, an EM test was performed under the conditions of a wiring temperature of 200 ° C. and a current density of 2 × 10 ⁶ A / cm ² . As a result, as shown in Tables 15 to 19 , the Al metal wiring formed on the amorphous thin film
It was found to have high EM resistance. As a comparative material, Al was directly deposited on the thermal oxide film without depositing an amorphous thin film.
Was deposited, and an EM test was performed in the same manner.
The wiring was broken within 0 hours.

[Table 15]

[Table 16]

[Table 17]

[Table 18]

[Table 19]

[0220] (Example 49) Si (100) after a thermal oxide film a 6-inch substrate 1000 angstroms formed, Table
An alloy thin film having each composition shown in Tables 20 to 33 was formed to a thickness of 1000 angstroms by mosaic target or multi-element simultaneous sputtering. Next, C is continuously applied without breaking vacuum.
A u film was formed to a thickness of 4000 angstroms, and further subjected to a heat treatment at 450 ° C. for 30 minutes in a vacuum. Here, the Cu film is formed under the condition that the vacuum is not deteriorated to the ultimate vacuum degree of 1 × 10 ⁻⁷ Torr or more, and the Ar gas pressure is 1.0 × 10 ⁻³ Torr.
r, 100 MHz RF output: 400 W, cathode bias voltage: -300 V, film formation rate: 40 Å / sec. In the samples shown in Table 32 , a -30 V bias was applied to the substrate during the formation of the Cu film. Thereafter, the half width of the rocking curve of Cu (111) was measured by X-ray diffraction, and the crystal orientation of the Cu film was evaluated. The results are shown in Tables 20 to 33 .

The crystallinity of the alloy thin film was evaluated by X-ray diffraction of a sample separately taken at the stage of forming the alloy thin film, and the presence or absence of an amorphous halo peak was confirmed.

Regarding the composition of the alloy thin film, since the target used for sputtering is 3N if the target has low purity, the impurity is mainly a homologous element which is difficult to separate at the time of purification (for example, Ta for Nb). However, the crystallinity did not affect the crystal orientation of the Cu film thereon.

Further, in order to examine the reliability as a metal wiring, a metal wiring made of a similar Cu film was formed on various alloy thin films, and an EM test was performed. FIG. 30 is a plan view of the test piece used at this time, and the process of preparing the test piece will be described below. First, after forming 3 μm of SiO ₂ on a Si substrate, PE
P and RIE processes were performed to form grooves of the four-terminal electrical resistance measurement pattern shown in FIG . However, the wiring width of the resistance measuring section was 1.0 μm, the depth was 4500 Å, and the wiring length was 1 mm. After the above-described SiO ₂ processing, 500 Å of various alloy thin films shown in Tables 20 to 33 were formed by collimation sputtering, and 6000 Å of Cu was formed under the above-described conditions, followed by heat treatment at 450 ° C. for 30 minutes. Was given. Thereafter, excess Cu was removed by CMP (Chemical-Mechanical Polishing) to obtain a test piece.

The EM test was performed in a vacuum at a wiring temperature of 300 ° C. and a current density of 2 × 10 ⁶ A / cm ² , and the results are shown in the table. The wiring resistance of the alloy wiring after the heat treatment was about 1.7 μΩcm in terms of specific resistance, which was almost equal to the bulk value of Cu, and no reaction between the alloy thin film and the Cu film due to the heat treatment was observed. Although the heat treatment method is a vacuum heat treatment in this embodiment, the heat treatment may be performed in a hydrogen atmosphere or a mixed gas of hydrogen and nitrogen (forming gas).
Although a Cu film was continuously formed after the alloy thin film was formed, if the sample was once exposed to the atmosphere after the alloy thin film was formed, the surface of the underlayer was plasma-cleaned in a vacuum before the Cu film was formed, and the natural oxidation was performed. After removing the film, a Cu film may be formed.

Further, in this embodiment, the underlying alloy thin film is made of T
In the case where the composition contains i, Zr, Hf, V, Nb, Ta, and Cr, NH ₃ or N ₂
By heating to 600 to 750 ° C in an atmosphere of C
When a nitride film was formed on the u surface and at the interface between the underlying film and the Cu film, no increase in electrical resistance was observed even after the subsequent TEOS film formation, and the oxidation resistance was extremely improved. Where T
Regarding compositions not containing i, Zr, Hf, V, Nb, Ta, and Cr, Ti, Zr, Hf, V, N
Similar results can be obtained by adding 1 to 10 at% of b, Ta, and Cr.

Further, as shown in Table 32 , by applying a bias of −20 to −50 V to the substrate during Cu film formation, the orientation of the Cu film is improved, and the composition range in which the EM resistance is good can be widened. .

Tables 31 and 32 show the results of a similar evaluation of a Cu film having no underlying alloy thin film as a comparative material.

EXAMPLE 50 A 6-inch silicon wafer provided with a 4000 Å thermal oxide film was formed as shown in FIG.
A groove having a shape similar to that shown in (a) and a depth of 2000 Å and a width of 1 μm was formed. Then
2000 Å of Al was deposited on the substrate. The K cell temperature of Al deposition is 1200 ° C., and the substrate temperature is room temperature. Observation of the surface and cross-sectional shape of this Al film using an SEM revealed that Al was uniformly deposited on the groove portion and on the surface of the thermal oxide film other than the groove, as shown in FIG. I was

On the same grooved substrate, an Al film was deposited at 2,000 Å under the same conditions as described above. The substrate temperature is room temperature. 40 without breaking the vacuum
Heat treatment was performed at 0 ° C. for 3 hours. When the surface and cross-sectional shape of the Al film after the heat treatment were observed using an SEM, FIG.
As in the case of (c), it is confirmed that the groove portion of the substrate is almost completely buried by the metal wiring made of Al, while Al is hardly deposited on the surface of the thermal oxide film other than the groove. Was done.

Next, on a similar grooved substrate, Al200
0 Angstrom and BilML were co-deposited early in the Al deposition. The conditions for depositing Bi are the same as those in Example 31, and the conditions for depositing Al are as described above. The substrate temperature is also room temperature. Subsequently, the sample was heat-treated at 200 ° C. for 3 hours without breaking vacuum. When the surface and cross-sectional shape of the Al film after the heat treatment were observed by using an SEM, the groove portion was almost completely buried by the metal wiring made of Al, as shown in FIG. It was confirmed that Al was hardly deposited on the surface of the thermal oxide film other than the grooves.

In addition to Bi, Ga, In, Cd, Sn, P
Similar results were obtained for b and Tl.

[Table 20]

[Table 21]

[Table 22]

[Table 23]

[Table 24]

[Table 25]

[Table 26]

[Table 27]

[Table 28]

[Table 29]

[Table 30]

[Table 31]

[Table 32]

[Table 33]

[0232]

As described above, according to the present invention, it is possible to provide an electronic component having highly reliable metal wiring.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating the operation of the present invention.

FIG. 2 is a sectional view showing a layer structure of the present invention.

FIG. 3 is a sectional view showing a metal wiring structure of the present invention.

FIG. 4 is a diagram showing a multi-target sputtering apparatus used in the present invention.

FIG. 5 is a sectional view according to the first embodiment of the present invention.

FIG. 6 is a sectional view according to a third embodiment of the present invention.

FIG. 7 is a sectional view according to a fifth embodiment of the present invention.

FIG. 8 is a sectional view according to a sixth embodiment of the present invention.

FIG. 9 is a sectional view according to a seventh embodiment of the present invention.

FIG. 10 is a sectional view according to an eighth embodiment of the present invention.

FIG. 11 is a perspective view showing a wiring manufacturing process according to a ninth embodiment of the present invention.

FIG. 12 is a characteristic diagram showing a result of an acceleration test according to Example 9 of the present invention.

FIG. 13 is a sectional view according to a tenth embodiment of the present invention.

FIG. 14 is a plan view showing a test board having a wiring section according to Embodiment 11 of the present invention.

FIG. 15 is a sectional view according to a fourteenth embodiment of the present invention.

FIG. 16 is a sectional view according to a sixteenth embodiment of the present invention.

FIG. 17 is a sectional view according to a seventeenth embodiment of the present invention.

FIG. 18 is a sectional view according to Embodiment 18 of the present invention;

FIG. 19 is a sectional view according to a nineteenth embodiment of the present invention.

FIG. 20 is a sectional view according to a twenty-first embodiment of the present invention.

FIG. 21 is a sectional view showing L / S defined by the present invention.

FIG. 22 is a sectional view showing a manufacturing process according to Example 23 of the present invention.

FIG. 23 is a sectional view according to a twenty-fifth embodiment of the present invention.

FIG. 24 is a sectional view according to a twenty-seventh embodiment of the present invention.

FIG. 25 is a RHEED photograph showing a crystal structure of an Al film according to Example 30 of the present invention.

FIG. 26 is a cross-sectional view according to a working example 35 of the invention.

FIG. 27 is a sectional view according to a working example 38 of the invention.

FIG. 28 is an SEM photograph showing a crystal structure of an Al film according to Example 41 of the present invention.

FIG. 29 is a perspective view according to Embodiment 43 of the present invention.

FIG. 30 is a plan view showing a four-terminal pattern according to a working example 49 of the invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Metal wiring, 3 ... Amorphous thin film, 5 ... Insulating layer, 6 ... Barrier layer, 7 ... Doped layer, 30, 38 ... Groove, 3
7: polycrystalline film, 50: control layer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Tomita 1 Toshiba-cho, Komukai-shi, Kawasaki-shi, Kanagawa Pref. Toshiba R & D Center (72) Inventor Takashi Kawanoue Komukai, Sachi-ku, Kawasaki-shi, Kanagawa 1 Toshiba Town R & D Center, Toshiba Corporation (72) Inventor Akihiro Kajita 1 Koyuki Toshiba Town, Yuki-ku, Kawasaki, Kanagawa Prefecture Inside R & D Center Toshiba Corporation (72) Inventor Takashi Kawakubo, Yuki-ku, Kawasaki City, Kanagawa Prefecture No. 1, Komukai Toshiba, Toshiba Corporation R & D Center (72) Inventor Masami Miyauchi No. 1, Komukai Toshiba, Yuki-ku, Kawasaki-shi, Kanagawa Prefecture Toshiba Corporation R & D Center (72) Inventor, Yoshiyo Ito Kawasaki, Kanagawa No. 1, Komukai Toshiba-cho, Sachi-ku Toshiba R & D Center (56) References JP-A-2-82651 (JP, A) JP-A-5-90421 (JP, A) JP-A-6-214255 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/3205 H01L 21/285 301

Claims (7)

(57) [Claims] 1. An amorphous thin film formed on a substrate, and a metal wiring formed on the surface of the amorphous thin film, wherein the metal wiring corresponds to a halo pattern peak appearing in a diffraction measurement of the amorphous thin film. characterized in that it is a /Ds≦0.25 | and interatomic distance ds of the surface interval df of a predetermined crystal plane defined by the first adjacent interatomic distance of the metal wiring is substantially aligned | df-ds Electronic components. 2. The method according to claim 1, wherein the metal wiring has a fcc structure of pure Al, pure Cu, pure Au, pure Ag, Al—Cu alloy, Al
-Ti alloy, Al-Cr alloy, Al-Ta alloy, Al-
Mg alloy, Al-In alloy, Al-Li alloy, Cu-B
e alloy, Cu-Ag alloy, Au-Pt alloy, Au-Ag
2. The electronic component according to claim 1, wherein the electronic component is mainly one of an alloy, an Au-Pd alloy, an Au-Cu alloy, and pure W having a bcc structure. 3. The electronic component according to claim 1, wherein a surface energy of a substance constituting said amorphous thin film in a crystalline state is larger than a surface energy of a substance constituting said metal wiring. 4. A metal element as a main component of the metal wiring,
The amorphous thin film comprises at least one of an element capable of forming an intermetallic compound with the metal element and an element capable of forming a solid solution with the metal element. Electronic component according to 1. 5. The method according to claim 1, wherein the amorphous thin film has a low content of Ti and TiN.
On the substrate via a barrier layer composed of at least one of
The electronic part according to claim 1, wherein the electronic part is formed.
Goods. 6. A groove is formed on a surface of the amorphous thin film.
The electronic component according to claim 1, wherein: 7. The metal wiring is formed by stacking a plurality of metal layers.
The electronic part according to claim 1, wherein the electronic part has a bent structure.
Goods.