JP3473302B2 - Method for forming coating type insulating film, method for manufacturing semiconductor device, and semiconductor device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a coating type insulating film and a method of manufacturing a semiconductor device, which is used as an interlayer insulating film of a multi-layer wiring of a semiconductor device to form a suitable coating type insulating film (SOG film). And a semiconductor device.

[0002]

2. Description of the Related Art In recent years,
In a semiconductor device, a multi-layer wiring technique is used to increase the capacity. Conventionally, a coating type insulating film (SOG film) has been used as an interlayer insulating film of the multilayer wiring of this semiconductor device.

The coating type insulating film (SOG film) is an insulating film containing SiO ₂ (silicon dioxide) as a main component, which is formed by coating and baking (heat treatment) a solution in which a silicon compound is dissolved in an organic solvent. Is a general term for.

When the interlayer insulating film is formed using this coating type insulating film (SOG film), this coating type insulating film (SO
The low molecular weight component present in the solution forming the (G film) is liable to volatilize because the vapor pressure at this time is low, and this low molecular weight component volatilizes before contributing to the crosslinking reaction during the heat treatment, which is Combined with oxygen to become particles,
There is the inconvenience of redepositing on this wafer.

These particles cause defects in the openings between the wirings and contacts, and thus have the disadvantage of reducing the yield of products.

In view of the above problems, the present invention proposes a method for forming a coating type insulating film, a method for manufacturing a semiconductor device, and a semiconductor device which prevent particles from being generated when forming the coating type insulating film. To aim.

[0007]

The method for forming a coating type insulating film according to the present invention is a method for forming a coating type insulating film, which comprises forming a coating type insulating film on an insulating film as an interlayer insulating film of a multilayer wiring structure. The heat treatment in the process of forming the coating type insulating film is performed in an atmosphere having a pressure higher than atmospheric pressure, such as 2 atmospheres. Preferably, after this heat treatment, the coating type insulating film is subjected to plasma treatment, and more specifically, the coating type insulating film is formed on the P-TEOS film. Further, in the method for manufacturing a semiconductor device of the present invention, after the coating type insulating film is applied on the insulating film as the interlayer insulating film of the multilayer wiring structure, the heat treatment in the process of forming the coating type insulating film is higher than atmospheric pressure, for example, 2 atmospheric pressure. After performing in a pressure atmosphere,
Wiring is formed in contact with the upper surface of the interlayer insulating film to form a multilayer wiring structure. Preferably, after the heat treatment, the coating type insulating film is subjected to plasma treatment, and then the above-mentioned wiring is formed, and further, the coating type insulating film is formed on the P-TEOS film.

According to the present invention, the heat treatment for coating the coating type insulating film on the insulating film as the interlayer insulating film of the multilayer wiring structure and forming the coating type insulating film is performed at a pressure higher than atmospheric pressure, for example, 2 atmospheric pressure. Since it was done in a high pressure atmosphere,
Volatilization of the low molecular weight component in the solution for obtaining the coating type insulating film is suppressed, and all the low molecular weight components undergo a cross-linking reaction to prevent the generation of particles.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the method for forming a coating type insulating film, the method for manufacturing a semiconductor device and the semiconductor device according to the present invention will be described below with reference to FIG.

In FIG. 1A, reference numeral 1 denotes a silicon substrate on which elements such as transistors and resistors are previously formed in an integrated manner, and a first interlayer insulating film 2 made of SiO ₂ or the like is formed on the silicon substrate 1, A first wiring 3 made of aluminum Al and having a predetermined pattern is formed on the first interlayer insulating film 2. The thickness of the first wiring 3 is, eg, 600 nm.

Next, as shown in FIG. 1B, the first wiring 3
Plasma C over the entire surface of the first and second interlayer insulating films 2
The P-TEOS film 4, which is an insulating film, is formed by the VD method, and a coating type insulating film (SOG) is formed on the P-TEOS film 4.
A film) 5 is formed.

This P-TEOS film 4 is formed by plasma CVD.
The conditions for forming a film by the method are TEOS / O ₂ = 800 /
600 sccm, pressure 1133 Pa, substrate temperature 400
The electric power of RF was 700 W and the film thickness was 300 nm.

Further, the coating type insulating film (SOG
The conditions for forming the film) are as follows. As a material for obtaining this coating type insulating film (SOG film), FOX14 (trade name) manufactured by Dowcorning Co., Ltd. is used, and this is coated by a spin coating method, and the subsequent heat treatment is performed in a N ₂ atmosphere, a pressure of 2 atm, It was performed for 60 minutes in an atmosphere at a temperature of 375 ° C. so as to obtain a coating type insulating film (SOG film) having a film thickness of 250 nm.

In this case, since the pressure during the heat treatment is set to 2 atm, the volatilization of the low molecular weight components is suppressed, all the low molecular weight components undergo the crosslinking reaction, and no particles are generated.

Next, as shown in FIG. 1C, a plasma treatment is performed on the coating type insulating film 5 by oxygen plasma using oxygen ions as a main reactive species. This plasma treatment is performed in order to prevent the coating type insulating film 5 from being cracked by the developing solution in the lithography in the next step.

In this example, the P-TEOS film 4 and the coating type insulating film 5 form a second interlayer insulating film 8.

Next, as shown in FIG. 1D, a contact hole 7 for making a connection between the first wiring 3 and a second wiring 9 which will be described later is formed at a predetermined position of the second interlayer insulating film 8. It is formed using a lithography technique and an etching technique.

Next, as shown in FIG. 1E, a second wiring 9 having a predetermined pattern is formed on the second interlayer insulating film 8 and the first wiring 3 in the contact hole 7 by a well-known sputtering technique and lithography technique. It is formed by using an etching technique. The second wiring 9 is also made of aluminum Al and has a film thickness of 600 nm.

Next, as shown in FIG. 1F, a SiN film 10 as a protective film is formed on the second wiring 9 and the second interlayer insulating film 8, that is, the coating type insulating film 5 by using a plasma CVD method. A film was formed.

According to this example, a semiconductor device having a two-layer wiring can be obtained.

According to this example, a coating type insulating film (SOG film)
Since the pressure during the heat treatment for obtaining 5 was 2 atm, the volatilization of the low molecular weight components in the solution for obtaining this coating type insulating film (SOG film) was suppressed, all the low molecular weight components undergo a crosslinking reaction, and the particles are Does not occur.

Therefore, according to this example, there is no short circuit of the wiring or defective opening of the contact due to the particles, so that there is an advantage that the yield of the product is improved.

In the above-mentioned embodiment, the second interlayer insulating film 8 is described as an example in which the second interlayer insulating film 8 is composed of the two layers of the P-TEOS film 4 and the coating type insulating film 5. However, instead of this, as shown in FIG. The second interlayer insulating film 8 may be three layers of the P-TEOS film 4, the coating type insulating film 5 and the SiO ₂ film 11. in this case,
The SiO ₂ film 11 can be formed by the plasma CVD method.

In the above embodiment, an example of obtaining a semiconductor device having a two-layer wiring has been described, but it goes without saying that a semiconductor device having a multilayer wiring having three or more layers may be obtained in the same manner.

Further, in the above-mentioned embodiment, the pressure during the heat treatment for obtaining the coating type insulating film 5 is set to 2 atm, but by setting this to be higher than the atmospheric pressure, the same effect as the above can be obtained.

Further, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0027]

According to the present invention, according to the present invention, the heat treatment for applying the coating type insulating film on the insulating film as the interlayer insulating film of the multilayer wiring structure and forming the coating type insulating film, Since it is performed in an atmosphere having a high pressure such as 2 atmospheres higher than the atmospheric pressure, volatilization of the low molecular weight components in the solution for obtaining the coating type insulating film is suppressed, and all the low molecular weight components undergo a cross-linking reaction, resulting in particle formation. Occurrence can be prevented.

Therefore, according to the present invention, the short circuit of the wiring and the defective opening of the contact due to the particles do not occur, so that there is an advantage that the yield of the product is improved.

[Brief description of drawings]

FIG. 1 is a sectional view for explaining an embodiment of a method for forming a coating type insulating film, a method for manufacturing a semiconductor device, and a semiconductor device according to the present invention.

FIG. 2 is a sectional view for explaining another embodiment of the present invention.

[Explanation of symbols]

1 silicon substrate, 2 first interlayer insulating film, 3 first wiring, 4 P-TEOS film, 5 coating type insulating film, 7 contact hole, 8 second interlayer insulating film, 9 second wiring, 10 SiN film

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/316 H01L 21/768

Claims (8)

(57) [Claims] 1. A method of forming a coating-type insulating film, which comprises forming a coating-type insulating film on an insulating film as an interlayer insulating film of a multilayer wiring structure, wherein the heat treatment for forming the coating-type insulating film is performed at a high pressure higher than atmospheric pressure. The method for forming a coating type insulating film is characterized in that it is performed in an atmosphere of. 2. A method of forming a coating type insulating film, which is formed on an insulating film as an interlayer insulating film of a multilayer wiring structure, wherein the heat treatment for forming the coating type insulating film is performed at a high pressure of 2 atm. A method for forming a coating type insulating film, characterized in that it is performed in an atmosphere. 3. The method for forming a coating type insulating film according to claim 1, wherein after the heat treatment, the coating type insulating film is subjected to plasma treatment. Forming method. 4. The coating type insulating film according to claim 1, 2, or 3, wherein the coating type insulating film is formed on a P-TEOS film. Forming method. 5. A heat treatment for forming a coating type insulating film on the insulating film as an interlayer insulating film of a multilayer wiring structure and then forming the coating type insulating film is performed in an atmosphere having a pressure higher than atmospheric pressure or 2 atmospheric pressure. Then, a wiring is formed in contact with the upper surface of the interlayer insulating film to form a multilayer wiring structure, which is a method for manufacturing a semiconductor device. 6. The method of manufacturing a semiconductor device according to claim 5, wherein after the heat treatment, plasma treatment is performed on the coating type insulating film, and then wiring is formed in contact with an upper surface of the interlayer insulating film. A method of manufacturing a semiconductor device characterized by the above. 7. The method of manufacturing a semiconductor device according to claim 5, wherein the coating type insulating film is formed on a P-TEOS film. 8. A heat treatment for forming a coating type insulating film on an insulating film as an interlayer insulating film of a multilayer wiring structure and then forming the coating type insulating film is performed in an atmosphere having a pressure higher than atmospheric pressure or 2 atmospheric pressure. After that, the coating type insulating film is subjected to a plasma treatment, and then a wiring is formed in contact with the upper surface of the interlayer insulating film to form a multilayer wiring structure, which is formed by a forming method.