JP2002151394A - Method for processing substrate, and method for manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent corrosion of a metal film 2 due to residues of a release liquid at a washing time by enhancing substitution effects of the rinsing liquid in rinsing for the release liquid, when a semiconductor substrate 1 is sequentially executed for release liquid processing, rinsing, washing, and drying to remove resist. SOLUTION: The substitution effects are enhanced, by rinsing by heating isopropyl alcohol used for the rinsing liquid up to 40 to 60 deg.C, to reduce its viscosity to about 1/2 to 1/3 of that at the ambient temperature time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for removing a resist formed on a semiconductor substrate or the like and used for patterning.

[0002]

2. Description of the Related Art In a semiconductor device such as an LSI, to form a desired pattern on a semiconductor substrate, first, for example, a conductive film such as aluminum or a silicon oxide film is formed on the entire surface of the semiconductor substrate (hereinafter referred to as a substrate). Forming an insulating film of
A resist pattern is formed thereon, and the underlying conductive film or insulating film is selectively etched and processed using the resist pattern as a mask. Thereafter, an unnecessary resist film is removed. After the plasma treatment, the removal of the resist film is performed by a remover treatment using an organic amine-based or ammonium fluoride-based remover.

FIG. 4 shows a conventional resist removing method. First, the substrate on which an unnecessary resist film is formed is subjected to a stripping solution treatment with an organic amine-based or ammonium fluoride-based stripping solution to remove the resist film, and then isopropyl alcohol or the like is used as a rinsing solution. By the rinsing process, the stripping solution remaining on the substrate surface is replaced with a rinsing solution and removed, and then a water washing process and a drying process are performed to complete the resist removal. Since the stripping solution used in the stripping solution treatment as described above reacts with water to generate a strong alkali component and significantly corrodes the metal film, the rinsing process is performed as described above, and the rinsing solution is used to replace the stripping solution. After that, a washing process is performed. In this rinsing treatment, the substrate is immersed in a liquid tank in which a rinsing liquid is circulated.
Minutes at room temperature.

[0004]

However, since the rinsing process is performed only by convection and diffusion of the rinsing liquid in the liquid tank, a certain amount of time is required to sufficiently replace the stripping liquid. , If the substitution is not enough,
The metal film exposed during the water washing process is corroded to some extent. When the underlying layer of the resist film to be removed is fine metal wiring, damage to the wiring has been a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and can be sufficiently replaced with a stripping solution promptly in a rinsing process after a stripping solution process, and can be replaced by a water washing process. An object is to prevent an adverse effect on an underlying substrate.

[0006]

Means for Solving the Problems Claim 1 according to the present invention.
The method for treating a substrate described above removes unnecessary resist on the substrate by sequentially performing a stripping solution treatment on the substrate, a rinsing process for replacing the stripping solution with a rinsing solution, a washing process, and a drying process. The rinsing process is performed by heating a rinsing liquid containing alcohols.

According to a second aspect of the present invention, there is provided a substrate processing method according to the first aspect, wherein the rinsing treatment is performed by heating to reduce the viscosity of the rinsing liquid to about 1/2 to 1/3 of the normal temperature. It is.

According to a third aspect of the present invention, there is provided a substrate processing method according to the first aspect, wherein rinsing is performed by using isopropyl alcohol as a rinsing liquid and heating to about 40 to 60 ° C.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a resist pattern on a film to be processed on a semiconductor substrate; and etching the film to be processed using the resist pattern as a mask. Removing the unnecessary resist pattern, the removing of the resist pattern is performed by sequentially performing a removing liquid treatment, a rinsing treatment, a water washing treatment and a drying treatment according to any one of claims 1 to 3 on the semiconductor substrate. It is done by doing.

According to a fifth aspect of the present invention, in the method of manufacturing a semiconductor device according to the fourth aspect, a metal film is used as a film to be processed and an organic amine-based or ammonium fluoride-based stripping solution is used as a stripping solution. It was what was.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, Embodiment 1 of the present invention will be described. Here, a case where a desired pattern of an aluminum wiring film is formed on a semiconductor substrate will be described with reference to FIG. First, semiconductor substrate 1 (substrate 1)
An aluminum wiring film 2 is formed as a film to be processed on the entire upper surface, a resist film 3 is formed on the entire upper surface thereof (FIG. 1A), and it is exposed or drawn by an electron beam, and then developed. Thus, a resist pattern 3a is formed (FIG. 1B). Using the resist pattern 3a as a mask, the underlying aluminum wiring film 2 is selectively etched and processed (FIG. 1C).
Thereafter, the unnecessary resist film 3 is removed (FIG. 1).
(D)).

The removal of the unnecessary resist film 3 will be described below with reference to FIG. First, after ashing by plasma processing, the substrate 1 is subjected to a stripping solution treatment with an organic amine-based or ammonium fluoride-based stripping solution to remove the resist film 3, and subsequently, rinsed with isopropyl alcohol as a rinse solution. Apply. This rinsing treatment is for removing the stripping solution remaining on the surface of the substrate 1 by replacing it with a rinsing solution.
The mixture is heated to about 60 ° C. and circulated, and the three tanks are each processed for 5 minutes. Thereafter, a washing process and a drying process are performed to complete the resist removal.

FIG. 3 shows the relationship between the temperature and the viscosity of isopropyl alcohol. As shown in the figure, by heating to about 40 to 60 ° C., the viscosity becomes 1 / the value at normal temperature (20 ° C.).
It decreases to about 2/3. Thereby, in the rinsing process, the replacement of the isopropyl alcohol with the stripping solution by convection and diffusion in the liquid tank is effectively promoted. Since the boiling point of isopropyl alcohol is about 82 ° C.,
By heating at about 0 to 60 ° C., there is no fear of vaporization, and the viscosity can be sufficiently reduced to enhance the substitution effect. For this reason,
The rinsing liquid can be promptly and sufficiently replaced with the rinsing liquid, so that the rinsing processing time can be shortened, and the remaining of the stripping liquid during the water washing processing can be effectively suppressed. Thereby, it is possible to prevent the underlying aluminum wiring film 2 from being corroded at the time of the water washing process,
A desired aluminum wiring film pattern can be obtained with high reliability, and miniaturization can be promoted.

In the above-described embodiment, isopropyl alcohol is used as the rinsing liquid. However, a rinsing liquid containing other alcohols may be used, and the viscosity of the rinsing liquid is reduced to half that at normal temperature by heating. It is used after being reduced to about 1/3. At this time, care should be taken so that there is no fear of vaporization.
Thereby, the effect of replacement with the stripping liquid is enhanced, and the same effect as in the first embodiment is obtained.

The aluminum wiring film 2 is formed by the resist film 3.
Although the case of patterning is shown, even in the case of patterning a silicon oxide film or the like, if the metal film is exposed under the silicon oxide film by etching,
Since the metal film is exposed to the stripping liquid when the unnecessary resist film 3 is removed, the same effect as in the first embodiment can be obtained by heating the rinsing liquid during the rinsing process.

Further, the present invention can be applied not only to the case where a film pattern to be processed is formed on the semiconductor substrate 1 but also to a rinsing process after a stripping solution process for removing an unnecessary resist pattern on the substrate. The effect can be enhanced and the rinsing processing time can be shortened.

[0017]

As described above, according to the method for treating a substrate according to the first aspect of the present invention, a substrate is sequentially subjected to a stripping solution treatment, a rinsing process for replacing the stripping solution with a rinsing solution, a washing process, and a drying process. In addition, since the unnecessary resist on the substrate is removed, and the rinsing treatment is performed by heating a rinsing liquid containing alcohols, the viscosity of the rinsing liquid is reduced, and replacement with a stripping liquid is performed. It is effectively promoted, the rinsing time can be shortened, and the residual stripping solution can be further suppressed.

According to a second aspect of the present invention, there is provided the substrate processing method according to the first aspect, wherein the rinsing treatment is performed by reducing the viscosity of the rinsing liquid to about １ ／ to の of normal temperature by heating. In addition, the stripping solution can be promptly and reliably replaced with the rinsing solution.

According to a third aspect of the present invention, there is provided a substrate processing method according to the first aspect, wherein the rinsing liquid is heated to about 40 to 60 ° C. using isopropyl alcohol as a rinsing liquid. 1/2 to 1 at normal temperature
The removal liquid can be reliably reduced to about 確 実, and the release liquid can be promptly and reliably replaced with the rinse liquid.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a resist pattern on a film to be processed on a semiconductor substrate; and etching the film to be processed using the resist pattern as a mask. Removing the unnecessary resist pattern, the removing of the resist pattern is performed by sequentially performing a removing liquid treatment, a rinsing treatment, a water washing treatment and a drying treatment according to any one of claims 1 to 3 on the semiconductor substrate. Therefore, during the rinsing process, the stripping solution can be quickly and surely sufficiently replaced with the rinsing solution,
A highly reliable semiconductor device can be manufactured without adversely affecting a semiconductor substrate during a water washing process in a later step.

According to a fifth aspect of the present invention, in the method of manufacturing a semiconductor device according to the fourth aspect, a metal film is used as a film to be processed, and an organic amine-based or ammonium fluoride-based stripping solution is used as a stripping solution. Therefore, during the rinsing process, the stripping solution can be promptly and reliably replaced with the rinsing solution, and the metal film can be prevented from being corroded at the time of the water washing process in the subsequent step, and a highly reliable metal film pattern can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating a method for manufacturing a semiconductor device according to a first embodiment of the present invention;

FIG. 2 is a diagram showing a resist removing method according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a relationship between temperature and viscosity of isopropyl alcohol according to Embodiment 1 of the present invention.

FIG. 4 is a view showing a conventional resist removing method.

[Explanation of symbols]

1 semiconductor substrate, 2 aluminum wiring film to be processed, 3
Resist film, 3a resist pattern.

Claims (5)

[Claims] 1. A substrate processing method for removing unnecessary resist on a substrate by sequentially performing a stripping solution treatment on the substrate, a rinsing process for replacing the stripping solution with a rinsing solution, a water washing process and a drying process. A method for treating a substrate, wherein the rinsing treatment is performed by heating a rinsing liquid containing alcohols. 2. Heating to increase the viscosity of the rinsing liquid to 1 at room temperature.
2. The method for processing a substrate according to claim 1, wherein the rinsing process is performed with the ratio reduced to about ２〜 to １ ／. 3. The substrate processing method according to claim 1, wherein rinsing treatment is performed by using isopropyl alcohol as a rinsing liquid and heating to about 40 to 60 ° C. 4. A method for manufacturing a semiconductor device, comprising: forming a resist pattern on a film to be processed on a semiconductor substrate; etching the film to be processed using the resist pattern as a mask; and removing an unnecessary resist pattern. The removal of the resist pattern is performed by a stripping solution treatment.
A rinsing process, a rinsing process, and a drying process according to any one of the above, which are sequentially performed on the semiconductor substrate. 5. The method for manufacturing a semiconductor device according to claim 4, wherein a metal film is used as the film to be processed, and an organic amine-based or ammonium fluoride-based stripping solution is used as the stripping solution.