JPH06267954A - Forming method of metallic thin film - Google Patents

Abstract

PURPOSE:To enable a metallic thin film pertinent to the formation of fine wiring, etc., to be easily formed by a method wherein insulator layers in different material qualities are formed after specific pattern on a base substance layer comprising an insulator so that single crystalline metallic layers may be selectively formed on the base substance layer with no insulating layer formed thereon. CONSTITUTION:After the formation of an amorphous Sin. film 2a on an Si wafer 1 surface, an amorphous SiN film 3 and another amorphous SiO2 film 2b are successively deposition-formed. Next, the deposition-formed amorphous SiO2 film 2b is photoetched away to shapedly provide aperture parts 4 for exposing parts of the amorphous SiN 3. Later, Al thin films 5a are selectively deposition-grown on the exposed amorphous SiN film 3 (in the aperture parts 4) by CVD process. During this CVD growing process, the Al thin films 5a are not to be deposited on the amorphous SiO2 film 2b but to be selectively buried in the aperture parts 4 only wherein the amorphous SiN films 3 is exposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a metal thin film suitable for forming highly reliable fine wiring in the manufacture of semiconductor devices.

[0002]

2. Description of the Related Art In recent years, semiconductor devices, such as USI typified by D-RAM, have been highly integrated and have been provided with Al.
The processing width of wiring is very narrow and the pitch is narrow. In such fine wiring, a phenomenon called stress migration caused by thermal stress of a metal thin film forming the wiring and a phenomenon called electromigration caused by an increase in current density flowing through the wiring become prominent.
Then, due to these migration phenomena, a part of the wiring is damaged to cause the wiring to be broken, which deteriorates the reliability of the ULSI.

By the way, it has been reported that the stress migration and electromigration are caused by crystal grain boundaries of a metal thin film forming a fine wiring. For example, regarding stress migration
Proc. IEDM 89, pp677-680 by M. Hasunuma et al.
Regarding electromigration, T. Kawawanou
Proceedings of the Joint Lecture on Applied Physics by e et al. (1991), p.
639. discloses that in the case of a single crystal Al wiring having no crystal grain boundary, the wiring is not broken and has high reliability.

On the other hand, in the process of manufacturing a semiconductor device,
Since fine wiring is performed on an insulating film that is generally amorphous,
There is a problem that the fine wiring made of the Al single crystal film exhibiting the high reliability cannot be applied. In addition, in fine wiring such as ULSI in which the element is miniaturized and the degree of integration is improved, for example, the connection hole is deep and the diameter is small, and it is important to form a uniform wiring. For such requests,
Physical vapor deposition methods such as vacuum vapor deposition and sputtering
(PVD) or by chemical vapor deposition (CVD) using a metalorganic compound gas as a raw material, the formed metal thin film is subjected to etching patterning, or the metal thin film is selectively masked with a SiO ₂ film or the like. Depending on whether it is formed or not, fine wiring including connection holes is performed.

[0005]

However, when the metal thin film is formed over the entire surface, excellent step coverage and smoothness are required for the formed metal thin film in terms of workability of fine wiring. On the other hand, there is a problem that either the step coverage or the smoothness is poor. That is, the chemical vapor deposition method (CVD) has excellent step coverage as compared with the physical vapor deposition method (PVD), and selective growth not possible with the physical vapor deposition method (PVD) is possible, but on the other hand,
Due to the poor smoothness of the deposited / growth film, it is not suitable for fine wiring patterning.

When the SiO ₂ film is selectively formed as a mask, selective growth can be realized because the difference in chemical properties between the surface of the Si substrate and the surface of the SiO ₂ film is used. The temperature range of the Si substrate that can maintain the growth selectivity is narrow, and the conditions for deposition and growth of the metal thin film are severely set, which is not suitable for practical use in terms of mass productivity.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for easily forming a metal thin film suitable for forming highly reliable fine wiring and the like.

[0008]

A method of forming a metal thin film according to the present invention comprises a step of forming an insulating layer of a material different from that of the base layer in a predetermined pattern on a base layer made of an insulating material, and the insulating layer. A step of selectively depositing a metal layer having a three-dimensionally aligned crystal orientation by chemical vapor deposition on the surface of the base layer on which no layer is formed,
Another method of forming a metal thin film is to form an insulator layer on a base layer in a predetermined pattern and selectively deposit a metal layer on the surface of the base layer on which the insulating layer is not formed by chemical vapor deposition. Wherein the surface of the insulator layer is formed of a metal oxide that is more thermodynamically stable than the oxide of the metal that forms the metal layer. The forming method is a method for forming a metal thin film by chemical vapor deposition, which comprises a step of forming a thin film containing a transition metal on the surface of the formation region of the metal thin film, and a deposition start temperature of the thin film containing the transition metal. Supplying two or more different kinds of organic metal source gases, setting at least the temperature at the start of metal thin film deposition to a temperature lower than the metal deposition start temperature on the metal surface, and depositing the metal thin film from the source gas by chemical vapor deposition. The process of making Characterized in that it.

[0009]

In the first aspect of the present invention, for example, the base layer exposed by selectively opening the insulating layer on the surface of the amorphous insulating film substrate, and the second insulating layer opening peripheral wall surface. Based on the difference in the selective growth property from the above, a (single crystal) metal layer having a three-dimensionally uniform crystallographic orientation is easily deposited in the opening, and further, the entire surface of the insulator layer is formed into a single crystal. A thin metal film grows. In other words, the support substrate is made up of multiple layers of a base layer made of a material that easily deposits metal and an insulator layer made of a material that is hard to deposit metal, and when the insulator layer is selectively removed / opened, it is exposed by the opening. It is possible to deposit and grow, by chemical vapor deposition, a metal thin film having a three-dimensionally uniform crystal orientation (extremely close to a single crystal), which is highly resistant to stress migration and electromigration, on the formed substrate layer surface. Become.

According to the second aspect of the invention, an insulating layer layer containing a metal oxide film which is thermodynamically stabler than an oxide film of a metal forming a metal layer to be deposited / grown on the surface of a supporting substrate by chemical vapor deposition. By forming, the selection ratio between the insulating layer and the supporting substrate is generally set to be large. That is, generally, when vapor phase growth using an organic metal as a raw material occurs on the metal oxide, the metal portion of the organic metal adheres to the oxygen side on the surface of the metal oxide. That is, it is said that the reduction reaction of the substance constituting the surface occurs. If a metal oxide film (insulator layer) that is thermodynamically stable is used as a mask rather than a metal oxide forming a metal thin film, reduction by organometallic molecules becomes extremely difficult. Therefore, when an organic metal is used as a raw material, vapor phase growth (deposition) of a metal layer on the thermodynamically stable metal oxide is difficult. Therefore, for example, a part of the metal oxide layer (film) and a part of the Si oxide film are selectively removed to provide an opening exposing the surface of the Si substrate,
For example, when an Al film is grown by exposing it to an Al-based source gas, Al deposition (growth) on the metal oxide layer does not occur, and the metal film grows only on the selected region surface (exposed surface). become.

Further, in the third invention, the organometallic compound gas as a raw material is used in a mixed system of two or more kinds, and the decomposition / growth rates thereof are different from each other, and the decomposition / growth starting temperature is predetermined. As the temperature is set, a metal thin film having good flatness is formed. In other words, each organometallic compound gas acts as an autocatalyst to promote decomposition, suppresses deposition / growth of thin films,
After the deposition / growth of a metal thin film of about one atomic layer, the growth / growth is preferentially performed in the thickness direction of the growth film, so that a metal thin film with dramatically improved surface smoothness is formed. Become.

[0012]

EXAMPLES Examples of the present invention will be described in detail below.

Example 1 FIGS. 1 (a) to 1 (e) are a sectional view and a plan view schematically showing an embodiment of a method for forming an Al thin film. First, FIG. 1 (a) is a sectional view. For example, a substrate 1 such as a Si wafer is prepared, and an amorphous film having a thickness of about 100 nm is formed on the surface of the Si wafer 1.
After forming the SiO ₂ film 2a, the amorphous SiN film 3 having a thickness of about 50nm in the amorphous SiO ₂ film 2a surface, further wherein the amorphous S
An amorphous SiO ₂ film 2b having a thickness of about 10 nm is sequentially deposited and formed on the surface of the iN film 3. Then, in cross section in FIG. 1 (b), FIG.
As shown in plan view in FIG.
₂ Film 2b is photo-etched to 50 nm
Apertures 4 each having a side length of 20 nm were formed at a pitch of 1 to expose a part of the amorphous SiN film 3. The opening 4 preferably has a side length of about 20 to 200 nm.

Then, the Si wafer 1 with a part of the amorphous SiN film 3 exposed is set in a conventional chemical vapor deposition apparatus prepared in advance, and chemical reaction is performed using triisobutylaluminum as a source gas. By vapor phase epitaxy, Al5a was selectively deposited and grown on the exposed amorphous SiN film 3 (inside the opening 4) as shown in a sectional view in FIG. In depositing and growing the Al thin film 5a, the temperature of the Si wafer 1 was set to 300 ° C. In this chemical vapor deposition, the Al thin film 5a is not deposited on the amorphous SiO ₂ film 2b, and the Al thin film 5a is selectively formed only in the opening 4 where the amorphous SiN film 3 is exposed.
Filled with. It is considered that the expression of this selectivity is due to the difference in the electronegativity between O in the amorphous SiO ₂ film 2b and N in the amorphous SiN film 3 which constitute the insulator film. That is, basically, selectivity can be exhibited by combining two kinds of insulating films so that the insulating film containing atoms having low electronegativity is exposed in the opening 4.

In the present invention, the amorphous SiN film 3 may be finished in a state where it is selectively filled with the Al thin film 5a only in the exposed opening 4, but in FIG. As shown,
It is also possible to non-selectively deposit and grow Al5b to a thickness of about 400 nm on the entire surface including the Al thin film 5a filling the opening 4. The non-selective growth may be switched by setting the preheating temperature of the source gas to 200 ° C., and the non-selective growth may be performed by physical vapor deposition such as sputtering.

The Al thin film 5a formed by the above
When the crystallinity of the Al thin film 5a was examined by X-ray diffraction after heat treatment at 30 ° C for 30 minutes, only the (111) peak was observed as the diffraction peak of Al. It was confirmed that the rotation angle in the in-plane direction (Si top) was within 3 °, and that the Al thin film 5a and the like were almost single crystals. 2 shows the shape of the substrate and the deposited and grown Al.
It is a schematic diagram which shows the crystal orientation with thin films 5a and 5b.

Further, the deposited and grown Al thin films 5a and 5b.
To a line width of 1.5 μm,
The electromigration resistance was accelerated and evaluated under the conditions of ℃ and current density of 1 × 10 ⁷ A / cm ² , as shown in Fig. 3. The resistance change rate shows higher reliability than the conventional Al wiring. Had sex.

Example 2 In this example, a Si oxide film and a metal oxide film, which is more thermodynamically stable than AL oxide, are sequentially formed on a Si substrate, metal or Si wiring, and the Si oxidation is performed. Selective removal of a part of the material film and metal oxide film (formation of an opening) and exposure on the exposed Si substrate or metal or Si wiring in the atmosphere of Al source gas for CVD to expose This is an example in which an Al thin film is selectively grown on the formed region surface.

In the case of this embodiment, that is, when CVD is performed on the metal oxide film from the source gas of the organic metal, the metal part of the organic metal is generally attached to the oxygen side on the surface of the oxide film (the surface is formed). It is said that the reduction reaction of the substance that occurs occurs. Therefore, as a mask when performing CVD, a beryllium oxide film, a calcium oxide film, a cerium oxide film, an erbium oxide film, a lanthanum oxide film, a lithium oxide film, a lutetium oxide film, a magnesium oxide film, a neodymium oxide film, and a scandium oxide film. , Strontium oxide film, tantalum oxide film, thorium oxide film, yttrium oxide film, ytterbium oxide film, holmium oxide film, thulium oxide film, dysprosium oxide film, samarium oxide film, lithium-aluminum composite oxide film, sodium-aluminum composite oxide film Material film, beryllium-aluminum composite oxide film, magnesium-aluminum composite oxide film, or lithium
A titanium composite oxide film is used. Since these metal oxides are more thermodynamically stable than Si oxides and are extremely difficult to reduce by organic Al molecules, Al thin films using organic metal gas on these metal oxides as materials CV
Deposition and growth by D becomes extremely difficult.

Therefore, when the metal oxide film and the Si oxide film are partially removed to form an opening for exposing the Si substrate surface and the like, and an Al thin film is deposited and grown on the exposed surface, Selective growth of Al thin films is realized under a wide range of deposition conditions.

Next, this embodiment will be specifically described.

First, a Si oxide film is formed on the surface of a Si substrate by a normal process. After that, a metal oxide film (such as a beryllium oxide film) having a thickness of about 20 nm, which is more thermodynamically stable than AL oxide, is deposited on the Si oxide film. Next, the region (portion) forming the connection portion is selectively removed by, for example, a photo-etching method to form an opening portion (hole) penetrating the metal oxide film and the Si oxide film. Next, the partial pressure of triisobutylaluminum is 0.1 Torr, and the total pressure is 60 sccm of Ar gas of the carrier.
CVD was performed in a reduced pressure atmosphere of 1 Torr to form an Al thin film wiring as shown in cross section in FIG. In FIG. 4, 6 is
Si substrate, 7 is a Si oxide film, 8 is a metal oxide film which is thermodynamically more stable than AL oxide, 9 is an opening (hole), and 10 is an Al thin film wiring.

In the above specific example, Table 1 shows the relationship between each metal oxide selected as a metal oxide film thermodynamically stabler than AL oxide and the upper limit of the temperature at which the selective growth is performed. . The upper limit of the temperature at which selective growth occurs is Al on the oxide film.
Determined by the temperature at which thin film deposition begins. It can be seen from Table 1 that the temperature range in which selective growth occurs is certainly widened to the high temperature side when the above-mentioned metal oxide surface is used. (Table 1) Silicon oxide film 300 ℃ Beryllium oxide film 344 ℃ Calcium oxide film 350 ℃ Cerium oxide film 341 ℃ Erbium oxide film 350 ℃ Lanthanum oxide film 341 ℃ Lithium oxide film 339 ℃ Lutetium oxide film 349 ℃ Magnesium oxide film 341 ℃ neodymium oxide film 343 ℃ scandium oxide film 350 ℃ strontium oxide film 339 ℃ tantalum oxide film 350 ℃ thorium oxide film 346 ℃ yttrium oxide film 343 ℃ ytterbium oxide film 343 ℃ holmium oxide film 349 ℃ thulium oxide film 350 ℃ dysprosium oxide film 348 ℃ samarium oxide film 344 ℃ lithium-aluminum composite oxide film 339 ℃ sodium-aluminum composite oxide film 331 ℃ beryllium-aluminum composite oxide film 332 ℃ magnesium-aluminum composite oxide film 334 ℃ lithium-titanium composite oxide film 330 C. Example 3 The following example is for depositing and forming a metal thin film. This is a case where a metal thin film is formed by using a plurality of kinds of organometallic compounds having different starting temperatures as a source gas. The point is the selection and setting of. That is, when the substrate on which a metal thin film, for example, an Al thin film is deposited and grown, is Al, the first organic Al
It is necessary to select and set the deposition start temperature of the compound gas to a low temperature. In other words, the organic selected and set to the first low temperature
At the deposition start temperature of the Al compound gas, subsequent deposition / growth may be continued, or the temperature may be raised from the deposition start temperature of the first organic Al compound gas, but at least initially, the temperature is low as described above. Set to. Under these conditions,
The decomposition of the source gas on the deposition target substrate is promoted more than the decomposition of the source gas on the deposited film when the substrate temperature is relatively low. However, it can be achieved without lowering the deposition rate by forming another ultra-thin film of an atomic layer of AL and then supplying another Al-based source gas having a property of decomposing at a lower temperature and performing chemical vapor deposition. For example, first, by using triisobutylaluminum as a source gas, an Al ultrathin film is formed on a substrate to be deposited, and then by chemical vapor deposition using dimethylaluminum hydride that decomposes at a lower temperature as a source gas, a predetermined film thickness is obtained. Form an Al thin film. By such means, it becomes possible to form an Al thin film for wiring having an arbitrary film thickness at a high deposition rate. Then, in the second-stage chemical vapor deposition method, the surface of the deposition target substrate is already covered with the Al ultrathin film, so that the Al thin film can be grown while maintaining the surface smoothness.

Next, FIG. 5 (a) to FIG.
A specific example will be described with reference to (d). Here, an example of using an organic Al compound as the organic metal compound is shown, but the invention is not limited thereto.

Example 3a Triisobutylaluminum ((i-C ₄
H ₉ ) ₃ Al) and dimethyl aluminum hydride ((CH ₃ ) ₂ Al · H) were used to form Al thin films by thermal CVD. That is, as shown in cross-section in FIGS. 5 (a) and 5 (b), an amorphous Al—Pt metal thin film 13 is formed on the Si oxide film 12 on the surface of the deposition target substrate 11 by a sputtering method in order to accelerate the decomposition of the source gas. The one formed to a thickness of 20 nm was used. Here, the composition ratio of Al-Pt is Al: 60atomic%, Pt: 40atomic
%. In addition, in order to sufficiently accelerate the decomposition of the raw material gas, it is desirable that Pt is contained at 30 atomic% or more.

On the substrate 11 on which the amorphous Al--Pt metal thin film 13 is formed, the substrate temperature is set to 200.degree.
As shown in cross sections in (c) to (d), 100 sccm of triisobutylaluminum was supplied for 5 minutes, and dimethylaluminum hydride was continuously deposited for 7 minutes at the same substrate temperature. In this case, the supply of triisobutylaluminum formed an ultrathin film of Al of about 0.5 nm on Al-Pt, and the subsequent supply of dimethylaluminum hydride finally formed an Al thin film of about 200 nm thickness.

The Al thin film thus formed had an average surface roughness of 5 nm or less, and an Al thin film having excellent surface smoothness was obtained by chemical vapor deposition.

On the other hand, as a comparative example, when only 100 sccm of triisobutylaluminum was supplied for one hour at the same substrate and substrate temperature, although the surface smoothness of the Al thin film was about the same, the film thickness was about 6 nm and the deposition rate was about 6 nm. Is low. In addition, in the comparative example in which the substrate temperature was 300 ° C., triisobutylaluminum was supplied for 5 minutes, and then dimethylaluminum hydride was supplied for 7 minutes, the island temperature growth of Al became remarkable due to the high substrate temperature, and the average surface roughness was increased. Had a problem with smoothness of about 50 nm.
Furthermore, in a comparative example in which only 100 sccm of dimethyl aluminum hydride was supplied at a substrate temperature of 200 ° C.,
The average surface roughness was 10 nm, which was slightly inferior in smoothness.

Example 3b Triisobutylaluminum ((iC ₄ H
₉ ) ₃ Al) and trimethylamine alane ((CH ₃ ) ₃
NAlH ₃ ) was used to form an aluminum thin film by thermal CVD. That is, as the substrate to be deposited, on the Si oxide film, an amorphous Al-
A Pt metal thin film having a thickness of 20 nm formed by a sputtering method was used. Here, the composition ratio of Al and Pr is Al: 60atomic.
%, Pt: 40 atomic%. In order to sufficiently promote the decomposition of the raw material gas, it is desirable that Pt is contained at 30 atomic% or more.

On the substrate, triisobutylaluminum 100 sccm was supplied at a substrate temperature of 200 ° C. for 5 minutes, the substrate temperature was lowered to 160 ° C., and then trimethylamine alane was supplied for 2 minutes to deposit an Al thin film. In this case, the supply of triisobutylaluminum formed an Al ultra-thin film of about 0.5 nm on Al-Pt, and the subsequent supply of trimethylamine alane finally formed an Al thin film of about 200 nm thickness.
The Al thin film formed here had an average surface roughness of 3 nm or less, and an Al thin film having excellent surface smoothness was obtained by chemical vapor deposition.

As a comparative example, 100 sccm at a substrate temperature of 160 ° C.
When only trimethylamine alane was supplied, the average surface roughness was 20 nm, which was inferior in smoothness.

Example 3c In this example, triisobutylaluminum ((iC ₄ H ₉ ) ₃ Al) and dimethylaluminum hydride ((CH ₃ ) ₂ Al.H) were used as source gases, and heat C
An Al thin film was formed by VD. That is, as the substrate to be deposited, an amorphous Al-Pd metal thin film is sputtered on the Si oxide film in order to accelerate the decomposition of the source gas,
A film having a thickness of 20 nm was used. The composition ratio of Al and Pd is Al:
60atomic% and Pd: 40atomic%. It is desirable that Pd is contained in an amount of 30 atomic% or more in order to sufficiently accelerate the decomposition of the raw material gas.

100 sccm of triisobutylaluminum was supplied onto the above substrate at a substrate temperature of 200 ° C. for 5 minutes, and dimethylaluminum hydride was continuously added at the same substrate temperature.
Deposited for 7 minutes. In this case, the supply of triisobutylaluminum formed an ultrathin film of Al of about 0.5 nm on Al-Pd, and the subsequent supply of dimethylaluminum hydride finally formed an Al thin film of about 200 nm thickness.

The average surface roughness of the formed Al thin film is 5 nm.
The following were obtained, and an AL thin film having excellent surface smoothness was obtained by chemical vapor deposition.

As a comparative example, a case where a metal thin film for promoting decomposition of the raw material gas was not formed was used. As a substrate for deposition, on the silicon oxide film and Si (100) single crystal, Si (11)
1) When single crystal was used, aluminum deposition by triisobutylaluminum did not occur at a substrate temperature of 200 ℃.

Example 3d Triisobutylaluminum ((iC ₄ H
₉ ) ₃ Al) and dimethyl aluminum hydride ((CH ₃ ) ₂ Al · H)) were used to selectively bury aluminum in the via holes by thermal CVD. That is,
As shown schematically in FIGS. 6 (a) and 6 (f), the substrate to be deposited has a cross section shown in FIGS. 6 (a) to 6 (c).
Amorphous Al-Pt thin metal film layer 13 is
After forming a 1 nm thick Si oxide film as an interlayer insulating film 15 on this, a predetermined position of this Si oxide film 15 is opened up to the amorphous Al-Pt layer, and a cross section is shown in FIG. 6 (d). As shown, a via hole 16 was used. We prepared three types of via holes 16 with diameters of 1 μm, 0.5 μm, and 0.25 μm. As shown in the sectional views of FIGS. 6 (e) to 6 (f), 100 sccm of triisobutylaluminum was supplied at a substrate temperature of 200 ° C. for 5 minutes on each of these substrates, and dimethylaluminum hydride was continuously added at the same substrate temperature. 35
Al layer 17 was deposited for minutes.

Under the above conditions for forming the Al thin film, Al was selectively embedded only in the via hole 16, and the average surface roughness of the embedded Al layer 17 was 5 nm or less. Further, the deposition rate of the Al layer 17 to be embedded did not depend on the diameter of the via hole 16, and the flatness of the substrate surface after the filling was improved, and the Al wiring layer was easily formed.

[0038]

According to the method for forming a metal thin film of the present invention, stress migration and electromigration are performed.
Crystal orientations with high resistance to ionization are three-dimensionally aligned
An Al thin film can be formed, and the metal thin film thus formed is suitable for forming fine wiring. In other words, since the metal thin film for fine wiring can be formed on the amorphous insulating film, a ULSI with greatly improved reliability can be obtained even in a ULSI structure or the like, so that its industrial value is extremely large. Further, according to the method for forming an Al thin film of the present invention, an Al thin film having excellent surface smoothness can be formed by the chemical vapor deposition method. It can be said that it is possible to form the above, and it brings many advantages practically.

[Brief description of drawings]

1 (a), (b), (c), (d), and (e) are cross-sectional views and plan views each schematically showing an embodiment of a thin film forming method according to the present invention in the order of steps.

FIG. 2 is a schematic view showing a crystal orientation and a substrate shape of an Al metal thin film formed by the thin film forming method according to the present invention.

FIG. 3 is a curve diagram showing an example of electromigration resistance of an Al metal thin film formed by the thin film forming method according to the present invention.

FIG. 4 is a cross-sectional view showing a structural example in which an Al metal thin film is selectively formed by the thin film forming method according to the present invention.

5 (a), (b), (c) and (d) are cross-sectional views schematically showing another embodiment example of the thin film forming method according to the present invention in the order of steps.

6 (a), (b), (c), (d), (e), and (f) are schematic diagrams of still another embodiment of the thin film forming method according to the present invention, in the order of steps. Sectional drawing to show.

[Explanation of symbols]

1, 11 ... Si wafer- (Si substrate) 2a, 2b ... Amorphous SiO
₂ film 3 ... Amorphous SiN film 4, 9 ... Openings 5a, 5
b ... Al thin film 7,12 ... Si oxide film 8 ... Metal oxide film thermodynamically stabler than Al oxide 13 ... Amorphous
Al-Pt layer 10, 14 ... Al wiring 15 ... Insulating film 16 ... Via hole
17 ... Al layer

Front page continuation (72) Inventor Shinichiro Okude 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Within the Corporate Research and Development Center, Toshiba Corporation (72) Inventor Kei Toyota, Komukai-shi Toshiba-cho, Kawasaki-shi, Kanagawa Banchi Co., Ltd. Toshiba Research & Development Center

Claims (3)

[Claims] 1. A step of forming an insulator layer of a material different from that of the base layer in a predetermined pattern on a base layer made of an insulator, and a step of selectively chemically forming a base layer surface on which the insulating layer is not formed. And a step of depositing a metal layer having a three-dimensionally uniform crystallographic orientation by vapor phase growth. 2. A step of forming an insulating layer in a predetermined pattern on the base layer, and a step of selectively depositing a metal layer by chemical vapor deposition on the surface of the base layer on which the insulating layer is not formed. A method of forming a metal thin film, characterized in that the surface of the insulator layer is formed of a metal oxide that is more thermodynamically stable than an oxide of a metal forming the metal layer. 3. A method for forming a metal thin film by chemical vapor deposition, comprising the steps of forming a thin film containing a transition metal on the surface of the formation region of the metal thin film, and a deposition start temperature on the thin film containing the transition metal. Of two or more different kinds of organometallic raw materials are supplied, the temperature at the start of metal thin film deposition is set at a temperature lower than the metal deposition start temperature for the metal surface, and the metal thin film is formed from the raw material gas by chemical vapor deposition. A method for forming a metal thin film, comprising the step of depositing.