JP2000150510A - Composite porous insulating film and formation method therefor, and, electronic device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the mechanical strength of a composite porous insulating film by forming a composite gel coat comprising an organic silicon compound and organic metal compound on a substrate, and thermally processing the composite gel coat. SOLUTION: On a semiconductor substrate 1, a wiring layer 3 of line and space pattern which comprises a lower layer interlayer insulating film 2 and an Al group metal is formed, which is to be a substrate. Over it, the sol of alkoxide compound of silicon and titanium is coated to form a composite porous gel coat. The porous gel coat is baked to form a composite porous insulating film 4. Thus, the mechanical strength of the composite porous insulating film 4 is raised, so deformation of the composite porous insulating film 4 and an inorganic insulating film or cracking are avoided under stress at CMP work or at the case when impact is applied. Thus, the reliability of an electric device employing a composite porous insulating film as a low permittivity film is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite porous insulating film, a method for forming the same, and an electronic device and a method for manufacturing the same. The present invention relates to a composite porous insulating film having improved strength, a method for forming the same, and an electronic device and a method for manufacturing the same.

[0002]

2. Description of the Related Art ULSI (Ultra Large Scale Integrate)
As the degree of integration of semiconductor devices such as d circuits increases, the wiring width and the wiring pitch need to be finer. At the same time, in order to meet the demand for low power consumption and high operating speed of high-integration semiconductor devices, especially high-speed logic semiconductor devices, the selection of a low dielectric constant interlayer insulating film material is necessary. It is gaining importance as one of the elemental technologies. This is an equally important problem in various microelectronic devices that process high frequency or digital signals, in addition to semiconductor devices.

[0003] Insulating film materials conventionally used for interlayer insulating films of semiconductor devices and the like include SiO ₂ (dielectric constant 4), S
iON (relative permittivity 4 to 6) or Si ₃ N ₄ (relative permittivity 6)
And other inorganic materials. As a method of reducing the capacitance between wirings of a highly integrated semiconductor device, for example, Japanese Patent Application Laid-Open
As disclosed in Japanese Patent Publication No. 50, it is effective to use an interlayer insulating film made of a material having a lower dielectric constant than these general inorganic materials. Representative examples of the low dielectric constant material include an inorganic insulating film material such as a silicon oxide insulating film containing fluorine atoms (hereinafter, referred to as SiOF) and an organic insulating film material containing carbon atoms.

[0004] SiOF is Si-O constituting SiO _2.
By terminating the F atoms to -Si bonds, that the density decreases, and the Si-F bonds and that O-F bond polarizability is small or the like, a low dielectric constant can be achieved than SiO _2. Since this SiOF is similar in film formation and etching process to conventional SiO ₂ , it can be easily adopted even in a current production apparatus. Also, since it is an inorganic material, it has excellent heat resistance.

A method of forming a SiOF film is described in TEOS (Tetra
Ethyl Ortho Silicate) as a silicon source gas, and CVD (Ch
emical Vapor Deposition) method is used. Method using C ₂ F ₆ as a fluorine source gas (25th SSDM Proceedings, p. 161 (1993)), Method using NF ₃ (40th Federation of Applied Physics-related lectures (Spring Annual Meeting, 1993)) Proceedings of Lectures, p.495, Lecture Number 1a-ZV-
9) has been reported. However, these methods use Si
It has also been reported that as the content of fluorine in the OF increases, the film quality deteriorates, and accordingly, the hygroscopicity significantly deteriorates.

In order to stabilize the film quality, SiF ₄ is adopted as a gas containing both silicon and fluorine, and SiF ₄ /
Plasma CVD method using O ₂ mixed gas and dissociating it by high-density plasma to form a film (Proceedings of the 40th Joint Lecture Meeting on Applied Physics (Spring Annual Meeting, 1993), p.
752, lecture number 31p-ZV-1) has also been proposed. SiOF obtained by this method is excellent in embedding characteristics even when the underlying substrate to be processed has a step with a high aspect ratio.

[0007] SiOF by high-density plasma CVD of a mixed gas of SiF ₄ / O ₂ is used in a region of low concentration of fluorine.
Higher film quality stability than F is secured. However, SiOF containing a high concentration of fluorine generates a Si = F ₂ bond in addition to a Si—F bond and an OF bond, which causes a problem of increased hygroscopicity. When the amount of water in the SiOF increases, the filling characteristics of the metal layer and the like in the contact plug forming step and the like decrease. Therefore, it is reported that the relative dielectric constant of SiOF formed by this method is limited to about 3.8 from the viewpoint of hygroscopicity.

Accordingly, an organic resin-based insulating film has been proposed for further lowering the dielectric constant. As a method for forming an organic resin-based insulating film, for example, a method has been proposed in which a paraxylylene resin containing fluorine is vapor-phase grown by using both a thermal decomposition reaction and a thermal polymerization reaction of a dimer (dimer) source gas. (VLSI / ULSI Multilevel Interconnection Conference
p.207 (1996)). The organic resin-based insulating film obtained by this method has a low dielectric constant of about 2.3.
However, a vapor phase growth method using both a thermal decomposition reaction and a thermal polymerization reaction requires a special raw material compound, and also requires a special structure for a vapor phase growth apparatus, and is therefore less versatile.

As another method of forming an organic resin-based insulating film,
There is a method in which an organic resin synthesized in advance is dissolved in a solvent and a film is formed by a coating method. This method is simple and can form a film by a usual spin coater or the like. In addition, an insulating film having a relatively low relative dielectric constant can be formed by selecting an organic resin. However, it is difficult to completely prevent the incorporation of low molecular weight components formed simultaneously with the synthesis of the organic resin and the effect of the residual solvent. In particular, when applied to an interlayer insulating film of a semiconductor device, in a metallization process of interlayer connection, volatilization and thermal decomposition of low molecular weight components due to insufficient heat resistance,
Alternatively, outgas is generated due to a residual solvent or the like, and the contact plug shape and contact resistance are deteriorated.

In addition to the above-described method of lowering the dielectric constant of an insulating film by selecting a material, there is an attempt to achieve a low dielectric constant by using a structure of the insulating film. This is a porous insulating film in which micropores (voids) are introduced into the insulating film, and porous silicon oxide is known.

[0011]

Since the porous insulating film is porous, it has a large specific surface area, and is therefore easily affected by the atmosphere. Specifically, it adsorbs moisture and the like in the atmosphere, and therefore, the relative dielectric constant, which is originally low, rises. In the case of adopting it for an interlayer insulating film or the like, outgas is generated in a heat treatment in a step of opening a connection hole here and embedding a contact plug (Interconnection), resulting in poor embedding and an increase in contact resistance.

Therefore, when the porous insulating film is put into practical use, a hydrophobic treatment is performed to improve the hygroscopicity. As an example, the present inventor has proposed a method of hydrophobizing the surface of a porous insulating film with a silicone compound as disclosed in Japanese Patent Application No. 10-240575. In this method, the porous insulating film is subjected to a reflux treatment in a dry non-aqueous solvent in which a silicone compound is dissolved, and this method has solved the problem of water absorption of the porous insulating film.

However, the porous insulating film has another problem that the mechanical strength is low. That is, when the film is applied as an interlayer insulating film of an electronic device such as a semiconductor device because it has fine pores in the film, chemical mechanical polishing (CMP) in a later step is performed.
In a process involving mechanical distortion such as a polishing process or a bonding process, a sufficient stress cannot be applied, and cracks or the like may occur.

The present invention has been made in view of such problems of the prior art. That is, an object of the present invention is to provide a composite porous insulating film having improved mechanical strength, a method for forming the same, a highly reliable electronic device such as a semiconductor device using the same, and a method for manufacturing the same. And

[0015]

Means for Solving the Problems To achieve the above-mentioned object, the present inventors focused on the material of the porous insulating film, and used a composite oxide or composite oxide obtained by adding another metal element to conventional silicon oxide. The inventors have concluded that the nitride is suitable for this purpose, and completed the present invention.

That is, the method for forming a composite porous insulating film of the present invention comprises the steps of forming a composite gel coating containing an organic silicone compound and an organometallic compound on a substrate, and subjecting the composite gel coating to a heat treatment. It is characterized by having.

The composite gel coating desirably further contains a basic reaction accelerator. Examples of the basic reaction accelerator include inorganic bases such as NH ₃ and N ₂ H ₄ and organic base compounds such as methylamine, and those which are volatilized and removed in the heat treatment step are desirable.

Examples of the organic silicone compound include Si alkoxides such as tetraethoxysilane, triethoxysilane, tetramethoxysilane, and trimethoxysilane. As the organometallic compound, typically, Al,
Desirably, the alkoxide is at least one of Zr, Ti, Y, Hf and Ta.

The composite porous insulating film of the present invention is characterized by being formed by the above-described method for forming a composite porous insulating film.

That is, the composite porous insulating film of the present invention comprises:
It is characterized by containing a composite oxide or composite oxynitride of Si and typically at least one metal of Al, Zr, Ti, Y, Hf and Ta.
These are SiAlO, SiAlON, SiZrO, S
iZrON, SiTiO, SiTiON, SiYO, S
It is a compound represented in the form of iYON, SiHfO, SiHfON, SiTaO or SiTaON.

Next, a method for manufacturing an electronic device according to the present invention is characterized in that the above-described method for forming a composite porous insulating film is provided during a manufacturing process.

Further, an electronic device according to the present invention is characterized in that a composite porous insulating film formed by the above-described method for forming a composite porous insulating film is provided as an interlayer insulating film.

[Operation] The bending strength of silicon oxide, which has been conventionally used as a material for a porous insulating film, is 12 kgf.
/ Mm ² , for example, the bending strength of aluminum oxide, which is a compound of aluminum, is 100 kgf / mm 2
² , extremely high, and 25 kgf even with aluminum nitride
/ Mm ^{2, which} is twice or more the strength. Zr, Ti, Y,
The compounds of Hf and Ta show the same tendency.

Therefore, by forming a composite porous insulating film using a composite oxide or a composite oxynitride with these metals, it is possible to improve the mechanical strength.

The porosity or the diameter of the fine pores in the composite porous insulating film can be controlled by selecting the amount and type of the basic reaction accelerator and the timing of its addition. That is, the relative dielectric constant of the porous insulating film can be controlled. Therefore, even in a nitrided oxynitride-based composite porous insulating film containing a nitride having a relatively large relative dielectric constant,
It is possible to reduce the dielectric constant.

After the film is formed, the surface of the composite porous insulating film of the present invention may be subjected to a hydrophobic treatment to enhance the moisture resistance. As the hydrophobic treatment, a method of reflux treatment in a dry non-aqueous solvent containing a silicone compound is preferably employed. Examples of the silicone compound include hexamethylenediethoxysilane, triphenylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane,
For example, trimethylmethoxysilane or triethylmethoxysilane can be used.

The porous insulating film of the present invention can be easily formed by a spin coater for a composite gel coating and a heat treatment apparatus.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION

A semiconductor device will be described below as an example of an electronic device, and an example in which the present invention is applied to a process of forming an interlayer insulating film will be described with reference to FIG.

FIG. 1 is a schematic sectional view showing a main part of an example of a semiconductor device to which the present invention is applied. That is, a lower interlayer insulating film 2 and a wiring layer 3 are formed on a semiconductor substrate 1 of silicon or the like, and a step due to the wiring layer 3 is generated. On these structures, an interlayer insulating film composed of the composite porous insulating film 4 and the inorganic insulating film 5 is formed, and the surface thereof is flattened. A connection hole 6 facing the wiring layer 3 is opened in the composite porous insulating film 4 and the inorganic insulating film 5, and a contact plug composed of a barrier metal layer 7 and a metal layer 8 is buried in the connection hole 6. I have. As the barrier metal layer 7, a single layer or a laminate of a high melting point metal such as Ti, Ta, Zr, or a nitride thereof is adopted. The metal layer 8 is formed from W, Al or Cu. The semiconductor device shown in FIG. 1 shows only relevant parts related to the present invention, and elements such as transistors formed on the semiconductor substrate 1 and upper wiring layers formed on contact plugs are all shown. Is omitted.

A feature of the semiconductor device shown in FIG. 1 is a composite porous insulating film 4. Since the composite porous insulating film 4 has improved mechanical strength as compared with a conventional porous insulating film made of silicon oxide, there is no possibility that deformation, cracks, and the like occur in the CMP step and the bonding step.
In addition, the dielectric constant is reduced by selecting the porosity of the fine holes, and the capacitance between wirings is reduced.

The semiconductor device as an example of the electronic device according to the present invention is not limited to the structure shown in FIG. 1, but may be an example in which a composite porous insulating film is formed directly on a semiconductor substrate, or a barrier formed on a flat composite porous insulating film. Various modifications are possible, such as a structure example in which a metal wiring layer having a metal layer as a lower layer is formed. Also, as an electronic device, in addition to a semiconductor device, it is suitably applied to various electronic devices such as a thin film magnetic head, a magnetoresistive head, a thin film inductor, a thin film coil, and a micromachine, particularly various electronic devices handling high frequency signals and digital signals. can do.

Hereinafter, as an example of a method of manufacturing an electronic device according to the present invention, a method of manufacturing the semiconductor device shown in FIG. 1 will be described in more detail with reference to FIG.

[Embodiment 1] This embodiment is an example in which a composite oxide of silicon and titanium is used as a composite porous insulating film.

FIG. 2 (a): The substrate employed in the present embodiment is a line-and-space pattern formed of a lower interlayer insulating film 2 made of SiO ₂ or the like and a Al-based metal on a semiconductor substrate 1 made of silicon or the like. The wiring layer 3 is formed. The surface of the base has grooves and steps due to the wiring layer 3.

FIG. 2 (b): A sol of an alkoxide compound of silicon and titanium was applied on this substrate under the following spin coating conditions to form a composite porous gel coating. Coating solution composition Tetraethoxysilane / ethanol solution (concentration 10%) Tetraisopropoxytitanium / IPA solution (concentration 5%) Ammonia water (concentration 2%) Rotation speed 3000 RPM

Next, the porous gel coating is fired,
A composite porous insulating film 4 was formed. The firing conditions were based on the following two-stage method. First-stage heat treatment: 150 ° C. for 10 minutes Second-stage heat treatment: 400 ° C. for 60 minutes The thickness of the composite porous insulating film 4 is set to, for example, 0.5 μm on the surface of the wiring layer 3. In the space between the wiring layers 3, a shallow concave portion is formed due to the film forming characteristics of spin coating.

FIG. 2C: Next, plasma CVD (Che
An inorganic insulating film 5 made of, for example, silicon oxide is formed to a thickness of, for example, about 0.8 μm by a mical vapor deposition method or the like, and the surface of the inorganic insulating film 5 is planarized by a CMP method. In the present embodiment, since the mechanical strength of the composite porous insulating film 4 is increased, deformation and cracking of the composite porous insulating film 4 and the inorganic insulating film even when stress or impact is applied during the CMP process. Is avoided.

FIG. 2D: A connection hole 6 facing the wiring layer 3 is opened by reactive ion etching. Immediately after cleaning the surface of the wiring layer 3 exposed at the bottom of the connection hole 6, Ti
A barrier metal layer 7 made of a single layer or a laminate of TiN or TiN is formed to a thickness of 70 nm by reactive sputtering. Subsequently, a metal layer 8 made of W is formed to a thickness of 800 nm by a blanket CVD method.
Polishing by a flattening method, the barrier metal layer 7
And a contact plug made of a metal layer 8 is buried.
This embedding step may be performed by etching back the entire surface. Further, the material of the metal layer 8 may be a material such as Cu or Al.

[0040] By this embodiment, the yield of non-defective deformation and a crack in the interlayer insulating film made of an inorganic insulating film 5 and the SiO ₂ composite porous insulating film 4 made of TiO ₂ did not occur was 100% . On the other hand, the yield of the sample manufactured in exactly the same manner except that the porous insulating film made of silicon oxide alone was used instead of the composite porous insulating film 4 was 15%.

Embodiment 2 This embodiment is based on Embodiment 1 except that a composite oxide of silicon and aluminum is used as the composite porous insulating film. Therefore, only the differences from the first embodiment will be mainly described. The substrate to be processed shown in FIG. 1A has the same configuration as that of the first embodiment.

FIG. 2B: A sol of an alkoxide compound of silicon and aluminum was applied on the substrate to be processed under the following spin coating conditions to form a composite porous gel film. Coating solution composition Tetraethoxysilane / ethanol solution (concentration 10%) Triisopropoxyaluminum / IPA solution (concentration 5
%) Ammonia water (concentration 2%) Rotation speed 3000 RPM

Then, the porous gel coating is fired,
A composite porous insulating film 4 was formed. The firing conditions were based on the following two-stage method. First-stage heat treatment: 150 ° C. for 10 minutes Second-stage heat treatment: 400 ° C. for 60 minutes The thickness of the composite porous insulating film 4 is set to, for example, 0.5 μm on the surface of the wiring layer 3. In the space between the wiring layers 3, a shallow concave portion is formed due to the film forming characteristics of spin coating.

The steps shown in FIGS. 2C to 2D are the same as those in the first embodiment, so that the overlapping description will be omitted.

Also according to the present embodiment, the inorganic insulating film 5,
The yield of non-defective products in which no deformation or cracks occurred in the interlayer insulating film composed of the composite porous insulating film 4 composed of SiO ₂ and Al ₂ O ₃ was 100%. On the other hand, except that a porous insulating film made of silicon oxide was used instead of the composite porous insulating film 4, the yield of a sample manufactured in exactly the same manner was 15%.

Third Embodiment The third embodiment is based on the first embodiment except that a composite oxynitride of silicon and titanium is used as the composite porous insulating film.
Therefore, only the differences from the first embodiment will be mainly described here. The substrate to be processed shown in FIG. 1A has the same configuration as that of the first embodiment.

FIG. 2 (b): A sol of an alkoxide compound of silicon and a titanium amino compound was applied to the substrate under the following spin coating conditions to form a composite porous gel coating. Composition of coating solution Tetraethoxysilane / ethanol solution (concentration 10%) Tetradimethylaminotitanium / IPA solution (concentration 5%) Methylamine aqueous solution (concentration 2%) Rotation speed 3000 RPM IPA is an abbreviation for isopropyl alcohol.

Next, the porous gel coating was fired to form a composite porous insulating film 4. The firing conditions were based on the following two-stage method. First-stage heat treatment: 150 ° C. for 10 minutes Second-stage heat treatment: 400 ° C. for 60 minutes The thickness of the porous insulating film 4 is, for example, 0.1 mm on the surface of the wiring layer 3.
The thickness is 5 μm. In the space between the wiring layers 3, a shallow concave portion is formed due to the film forming characteristics of spin coating.

The steps shown in FIGS. 2C to 2D are the same as those in the first embodiment, so that the overlapping description will be omitted.

According to the present embodiment, the inorganic insulating film 5,
The yield of non-defective products in which no deformation or cracks occurred in the interlayer insulating film made of the composite porous insulating film 4 made of SiO ₂ and AlN was 100%. On the other hand, the yield of the sample manufactured in exactly the same manner except that the porous insulating film made of silicon oxide alone was used instead of the composite porous insulating film 4 was 15%.

Embodiment 4 The moisture resistance of the composite porous insulating film of the present invention can be improved by subjecting the surface of the composite porous insulating film to a hydrophobic treatment. As an example, a step of refluxing a silicone compound in a dry non-aqueous solvent will be described.

First, an example of a reflux device used for surface treatment of a composite porous insulating film will be described with reference to a schematic sectional view shown in FIG. The reflux device shown in FIG. 3 is roughly divided into a treatment tank 10 and a reflux tower 20. The processing tank 10 has a substantially sealed closed internal space, and is connected to a first inlet pipe 14 and a second inlet pipe 15 for introducing a processing liquid, and a substrate 11 to be processed is placed in the inside thereof. There is a stage 12 to perform. The non-aqueous solvent 16 such as xylene injected from the first introduction pipe 14 is heated by the heater 13 and reaches its boiling point. The vapor of the non-aqueous solvent 16 fills the upper space of the processing tank 10. This vapor is generated by azeotropic distillation of a non-aqueous solvent, water and the like. The second introduction pipe 15 is a pipe for introducing a silicone compound.

The reflux tower 20 has a cooling unit 21 which is cooled by a circulating refrigerant or the like from a chiller 22 and a drain 24 which discharges moisture at a lower part thereof. They are connected by a reflux pipe 26.
With this configuration, the steam introduced from the upper space of the processing tank 10 is introduced into the reflux tower 20 from the steam reflux pipe 25,
It is liquefied in the cooling unit 21. The liquefied non-aqueous solvent and water fall to the lower part of the reflux tower 20, and the water 23 accumulates at the lowermost part.
The non-aqueous solvent 16 having a low specific gravity accumulates in the upper part of the water 23 and is returned to the processing tank 10 through the liquid reflux pipe 26.

The above-described reflux apparatus has a basic configuration, and various changes can be made. For example, the substrate 11 to be processed may be mounted in a batch system in addition to the single-wafer system, or may be mounted on a carrier or the like (not shown) and carried into the processing tank 10. Cooling unit 2
If 1 is cooled by a Peltier element, it contributes to downsizing of the entire apparatus.

The substrate to be processed having the composite porous insulating film 4 shown in FIG. 2B is set on the stage 12 of the reflux apparatus shown in FIG. 144 ° C.) is introduced into the processing tank 10. The liquid level of o-xylene as the non-aqueous solvent 16 is
Of the surface is sufficiently hidden. As the non-aqueous solvent, m-, p-xylene or a compound having no hydrophilic group, that is, a compound having no hydrophilic group, that is, a compound having no compatibility with water is selected in addition to o-xylene. The boiling point is preferably 100 ° C. or higher and 200 ° C. or lower in terms of handling. Next, the o-xylene is heated to the boiling point by the heater 13 to start reflux. By this reflux, the water adsorbed on the substrate 11 to be treated azeotropes with o-xylene, and the azeotropic vapor reaches the reflux tower 20 from the steam reflux pipe 25. Here, the azeotropic vapor is liquefied by the cooling unit 21 and dropped to the lower part of the reflux tower 20. At this time, water that is incompatible with o-xylene is separated and becomes water 23 at the lowermost portion of the reflux tower 20 due to a difference in specific gravity. On the other hand, the o-xylene is collected at the lower part of the reflux tower 20 but on the water 23, and is returned to the processing tank 10 through the liquid reflux pipe 26. This refluxed o-xylene is a dry non-aqueous solvent containing no water.

The reflux operation is continued for about 60 minutes, and the water adsorbed on the substrate 11 is almost completely desorbed. The water 23 at the bottom of the reflux tower 20 is appropriately discharged from the drain 24. This removal of adsorbed water is an important step, and when adsorbed water remains on the substrate 11 to be treated, in the next step of forming a surface treatment layer, a silicone compound such as hexamethylenediethoxysilane is dissolved in a solution. Since a reaction product is formed, the surface treatment layer cannot be formed stably.

Thereafter, the process for forming the surface treatment layer is immediately started. After the water 23 at the bottom of the reflux tower 20 is finally discharged from the drain 24, hexamethylenediethoxysilane is added as a silicone compound through the second inlet pipe 15 to the nonaqueous solvent 16
Add in. The addition amount of hexamethylenediethoxysilane is about 1% by weight of o-xylene. By continuing the reflux at the boiling point temperature of o-xylene, a hydrophobic surface treatment layer (not shown because it is thin) is formed on the surface of the composite porous insulating film 4.

The surface treatment may be applied to the exposed surface of the composite porous insulating film 4 on the side surface of the connection hole 6 after the opening of the connection hole 6 shown in FIG. By employing such a surface treatment, the mechanical strength of the composite porous insulating film 4 can be improved, and the moisture resistance can be improved.

Although the present invention has been described with reference to the four embodiments, the type of the composite oxide or composite oxynitride constituting the composite porous insulating film can be appropriately changed from those described above. . Further, the present invention may be applied to a passivation film other than the interlayer insulating film of the semiconductor device.

Further, in addition to the semiconductor device, the present invention is particularly suitably applied to various electronic devices such as a thin film magnetic head, a magnetoresistive head, a thin film inductor, a thin film coil, and a micromachine, particularly various electronic devices used in a high frequency band. Its performance and reliability can be improved.

[0061]

As is apparent from the above description, according to the method for forming a composite porous insulating film of the present invention, its mechanical strength is improved, and deformation and cracks in subsequent steps are prevented.
Therefore, by employing such a high-strength porous insulating film, the reliability of various electronic devices employing the composite porous insulating film as the low dielectric constant film can be improved. The composite porous insulating film of the present invention can be formed by a simple method without using special raw materials or complicated manufacturing equipment.

According to the electronic device and the method of manufacturing the same of the present invention, by applying such a composite porous insulating film and the method of forming the same, cracking or deformation of the interlayer insulating film in a post-process such as CMP or bonding can be achieved. Is prevented, the production yield is improved, and the performance and reliability of the electronic device can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a main part of a semiconductor device as an example of an electronic device employing a composite porous insulating film of the present invention.

FIG. 2 is a schematic cross-sectional view of a process in which the method for forming a composite porous insulating film of the present invention is applied to a method for manufacturing a semiconductor device as an example of an electronic device.

FIG. 3 is a schematic cross-sectional view of an example of a reflux device applied to a surface treatment method for a composite porous insulating film.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Semiconductor base, 2 ... Lower interlayer insulating film, 3 ... Wiring layer, 4
... composite porous insulating film, 5 ... inorganic insulating film, 6 ... connection hole, 7
... Barrier metal layer, 8 ... Metal layer 10 ... Treatment tank, 11 ... Substrate to be treated, 12 ... Stage, 13 ... Heater, 14 ... First
, 15 ... second inlet pipe, 16 ... non-aqueous solvent, 20
... reflux tower, 21 ... cooling unit, 22 ... chiller, 23 ... moisture,
24: drain, 25: vapor reflux tube, 26: liquid reflux tube

Continued on the front page F-term (reference) BC07 BC09 BF27 BF31 BF41 BF46 BF51 BF52 BF54 BG03 BH01 BH20 BJ01 BJ02 BJ03

Claims (8)

[Claims] 1. A composite porous insulating film comprising: a step of forming a composite gel coating containing an organosilicone compound and an organometallic compound on a substrate; and a step of subjecting the composite gel coating to a heat treatment. Forming method. 2. The method for forming a composite porous insulating film according to claim 1, wherein said composite gel coating further contains a basic reaction accelerator. 3. The method according to claim 1, wherein the organometallic compound is Al, Zr, T
at least one of i, Y, Hf and Ta
The method for forming a composite porous insulating film according to claim 1, wherein the compound is a kind of compound. 4. A composite porous insulating film formed by the method for forming a composite porous insulating film according to claim 1. 5. The composite porous insulating film according to claim 1, wherein the composite porous insulating film contains a composite oxide of Si and at least one metal selected from the group consisting of Al, Zr, Ti, Y, Hf and Ta. Item 5. A composite porous insulating film according to item 4. 6. The composite porous insulating film includes a composite oxynitride of Si and at least one metal of Al, Zr, Ti, Y, Hf and Ta. The composite porous insulating film according to claim 4. 7. A method for manufacturing an electronic device, comprising the method for forming a composite porous insulating film according to claim 1 in a manufacturing process. 8. An electronic device comprising a composite porous insulating film formed by the method for forming a composite porous insulating film according to claim 1 as an interlayer insulating film.