JP2001094056A - Semiconductor integrated circuit and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit that can be manufactured with a simple process and less manufacturing costs, so that a solution used in the process can be subjected easily to waste liquid treatment. SOLUTION: In this semiconductor integrated circuit with a semiconductor integrated circuit, where a semiconductor element is formed and a protective film formed on the semiconductor integrated circuit, the protective film is made of an inorganic insulation film and an organic insulation resin with positive photosensitive property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective film formed on a semiconductor integrated circuit substrate on which a semiconductor element is formed by covering the electrode with a through hole for leading an electrode for connecting the electrode to an external electrode. And a method of manufacturing the semiconductor integrated circuit having a structure suitable for forming a semiconductor integrated circuit on a protective film.

[0002]

2. Description of the Related Art A conventional method for manufacturing a semiconductor integrated circuit will be described below with reference to the accompanying drawings. FIG. 2 is a process chart for explaining a conventional method for manufacturing a semiconductor integrated circuit. First, an electrode 1 to be connected to an external electrode is formed on a semiconductor integrated circuit substrate 2 on which a semiconductor element (LSI) is formed, and an inorganic insulating protective film 10 (simply referred to as an inorganic protective film) is formed thereon. Is formed (FIG. 2A).

Next, a positive photoresist 30 is applied on the inorganic insulating protective film 10 and is preliminarily dried (FIG. 2B). Next, light 41 is irradiated to the portion of the positive resist 30 above the electrode 1 where a through hole is to be formed by the positive reticle 40 to form an exposed portion 31 (FIG. 2C).

Next, the positive photoresist 30 is coated with a non-solvent aqueous solution such as NMD-3 (Tokyo Ohka Kogyo Co., Ltd.).
), The exposed portion 31 is removed, and the through hole 6 is removed.
Then, the positive photoresist is finally cured and fixed by thermal curing (FIG. 2 (d)). Next, using the positive photoresist 30 as a mask, the inorganic insulating protective film 10 on the electrode 1 is removed by plasma etching or the like to form a through hole 61 exposing the electrode 1 (FIG. 2E). .

Next, the positive photoresist 30 is dissolved and removed (FIG. 2 (f)). Next, a negative type organic insulating resin 70 (also simply referred to as an organic protective film) is passed through the through hole 62.
At the same time, the entire surface of the inorganic insulating protective film 10 is covered and temporarily dried (FIG. 2 (g)), and the process immediately proceeds to the next step. The negative reticle 80 is arranged at a predetermined position, and the light 81 is irradiated to portions other than the upper portion of the electrode 1, leaving the unexposed portion 71 of the negative organic insulating resin 70. Immediately after this, post-exposure bake (hereinafter also referred to as PEB) is performed to promote the photoreaction after exposure of the negative type organic insulating resin 70.
Stabilization is attempted (FIG. 2 (h)).

Next, an organic solvent-based developer such as DV-6
05 (manufactured by Toray Industries, Inc.) and rinsed with isopropyl alcohol (hereinafter also referred to as IPA),
The unexposed portion 71 is removed to form a through hole 90, and thereafter, the negative type organic insulating resin 70 is dried (FIG. 2).
(I)). Thus, a through hole 90 is formed on the electrode 2 formed on the semiconductor integrated circuit substrate 2 to be connected to the external electrode, and the inorganic insulating protective film 1 is formed therearound.
0 and a negative type organic insulating resin 70 are formed.

[0007]

However, forming a through-hole on an electrode on a conventional semiconductor integrated circuit substrate requires two exposure and development steps and a post-exposure bake. Further, the developer of the negative type resin is mainly composed of N-methylpyrrolidone (hereinafter also referred to as NMP) which is a dangerous substance of the fourth kind and the third petroleum, and the rinsing liquid is a dangerous substance of the fourth kind. Alcohol I
It is a PA, and processing of these waste liquids requires cost, and it has been a problem to realize a simpler through-hole forming method.

Accordingly, the present invention solves the above-mentioned problems, and provides a semiconductor integrated circuit and a method of manufacturing the semiconductor integrated circuit, which can be manufactured by a simple process, the manufacturing cost is low, and the solution used in the process can be easily treated as a waste liquid. The purpose is to:

[0009]

According to a first aspect of the present invention, there is provided a semiconductor integrated circuit according to the present invention.
In a semiconductor integrated circuit having a semiconductor integrated circuit substrate on which a semiconductor element is formed and a protective film formed on the semiconductor integrated circuit substrate, the protective film is formed of an inorganic insulating film and an organic insulating resin having a positive photosensitive property. And a semiconductor integrated circuit characterized by the above.

According to a second aspect of the present invention, there is provided a method of manufacturing a semiconductor integrated circuit according to the present invention, which covers an electrode to be connected to an external electrode on a semiconductor integrated circuit substrate. Forming an inorganic protective film on the semiconductor integrated circuit substrate in a method of manufacturing a semiconductor integrated circuit in which electrode through holes for extracting the electrodes are formed in the formed inorganic protective film and organic protective film. Forming the organic protective film having a positive photosensitive property on the inorganic protective film, applying a positive photosensitive resin on the organic protective film, and forming the organic protective film on the electrode; Forming the through hole of a predetermined shape in the photosensitive resin by exposure and development; and etching the inorganic protective film on the electrode through the through hole to expose the electrode. Is intended to provide a method of manufacturing a semiconductor integrated circuit, characterized in that it comprises a step of.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a process chart for explaining an embodiment of a method of manufacturing a semiconductor integrated circuit according to the present invention.

First, an electrode 1 to be connected to an external electrode is formed on a semiconductor integrated circuit substrate 2 on which a semiconductor element (LSI) is formed, and an inorganic insulating protective film 1 is formed thereon.
0 (also simply referred to as an inorganic protective film) is formed. The inorganic insulating protective film 10 is for preventing intrusion of contaminants such as moisture and alkali ions which cause deterioration of the LSI. For example, a SiO ₂ film, a SiN film, or a multilayer film thereof is used by a CVD method. .

In this case, S
About 8 μm thick SiO ₂ using iH ₄ / N ₂ O mixed gas
A film is formed, and similarly, by a plasma CVD device,
An SiN film having a thickness of about 4 μm was formed using a mixed gas of SiH ₄ / NH ₃ / N ₂ (FIG. 1A).

Next, an organic insulating resin 20 having a positive type photosensitivity (hereinafter, also simply referred to as a positive type organic resin) is formed on the inorganic insulating protective film 10. The positive type organic resin 20 becomes an organic insulating protective film, and when the integrated circuit is finally sealed with a plastic package, the stress applied to the surface of the integrated circuit is reduced by a sealing agent made of, for example, an epoxy resin. Becomes a buffer membrane.

As the positive type organic resin 20, for example, CR
C-8300 (manufactured by Sumitomo Bakelite Co., Ltd .: polyimide-based positive photosensitive resin) is applied with a spinner,
After pre-baking at a temperature of about 10 ° C., a film of the positive type organic resin 20 having a thickness of about 10 μm was obtained (FIG. 1B). Next, on this positive type organic resin 20, a positive type photoresist 30, for example, THMR-iP3450 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied by spin coating, and prebaked at 110 ° C. to have a thickness of about 1 μm. A positive photoresist 30 film was formed (FIG. 1C).

Next, the positive type reticle 40 is arranged at a predetermined position, and light is collectively applied to predetermined portions of the positive type organic resin 20 and the positive type photoresist 30 on the electrode 2 using an i-line stepper. 41, the exposed portion 21 of the positive organic resin 20 and the exposed portion 31 of the positive photoresist 30
Was simultaneously formed (FIG. 1 (d)).

Next, a non-solvent aqueous alkaline solution, for example, tetramethylammonium hydroxide (TMA)
H) The positive-type organic resin 20 and the positive-type photoresist 30 are simultaneously developed using a 2.38% solution, and rinsed with pure water to remove the respective exposed portions 21 and 31 and remove the through holes 50. After drying at 110 ° C., the positive photoresist 30 was dried and cured (FIG. 1E).

Next, the inorganic insulating protective film 10 is passed through the through hole 50 using, for example, a plasma etching apparatus.
Is etched. At this time, a double film of the positive organic resin 20 and the positive photoresist 30 is used as a mask, and CF ₄ / Ar is used as a gas to be introduced into the SiN film.
/ O ₂ mixed gas, the SiO ₂ film, CHF ₃ / CF ₄ / A
r mixed gas is used. By this etching,
A through hole 51 reaching the electrode 1 was formed (FIG. 1 (f)).

Next, the positive photoresist 30 is dissolved and removed using a stripping solution. In this way, a through hole 52 is formed in the electrode portion on the integrated circuit board 2 and thereafter,
The positive type organic resin 20 was dried at 50 ° C. ((g) in FIG. 1).

As can be understood from the above description, in the integrated circuit of the present invention, since the positive type organic resin and the positive type photoresist having photosensitivity are formed on the inorganic insulating protective film, the integrated circuit is formed once. By performing the batch exposure and development processing, through holes can be formed,
Exposure / development steps can be reduced, and lead time and manufacturing cost can be reduced. Further, since there is no need to use a negative-type organic insulating resin, and no organic solvent-based developer is used, waste liquid processing equipment and processing costs are unnecessary, and manufacturing costs can be significantly reduced.

[0021]

As described above, the semiconductor integrated circuit according to the first aspect of the present invention comprises a semiconductor integrated circuit substrate on which a semiconductor element is formed and a protective film formed on the semiconductor integrated circuit substrate. In the semiconductor integrated circuit having the above, since the protective film is composed of the inorganic insulating film and the organic insulating resin having positive photosensitivity, the manufacturing cost is reduced by a simple process, and the solution used in the process is easily manufactured. In addition, there is an effect that a semiconductor integrated circuit that can be manufactured so that waste liquid can be treated can be provided.

Further, as described above, the method of manufacturing a semiconductor integrated circuit according to the second aspect of the present invention provides an inorganic protection circuit formed by covering an electrode to be connected to an external electrode on a semiconductor integrated circuit substrate. In a method for manufacturing a semiconductor integrated circuit, in which a film and an organic protective film are provided with through-holes for extracting electrodes for extracting the electrodes, a step of forming the inorganic protective film on the semiconductor integrated circuit substrate; Forming the organic protective film having positive photosensitivity on the protective film, applying a positive type photosensitive resin on the organic protective film, and forming the organic protective film on the electrode and the photosensitive A step of forming the through hole having a predetermined shape in a resin by exposure and development, and a step of exposing the electrode by exposing the inorganic protective film on the electrode through the through hole. By, by simple process, production cost reduced, moreover, the solution to be easily effluent processing used in step, there is an effect that it is possible to provide a method of manufacturing a semiconductor integrated circuit can be produced.

[Brief description of the drawings]

FIG. 1 is a process chart for explaining an embodiment of a method of manufacturing a semiconductor integrated circuit according to the present invention.

FIG. 2 is a process chart for explaining a method of manufacturing a conventional semiconductor integrated circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrode 2 semiconductor integrated circuit board 10 inorganic insulating protective film 20 positive organic insulating resin 21 exposed part 30 positive photoresist 31 exposed part 40 positive reticle 41 light 50 through hole 51 through hole 52 through hole 60 through hole 61 Through hole 62 Through hole 70 Negative organic insulating resin 80 Negative reticle 81 Light 90 Through hole

Claims (3)

[Claims] 1. A semiconductor integrated circuit having a semiconductor integrated circuit substrate on which a semiconductor element is formed and a protective film formed on the semiconductor integrated circuit substrate, wherein the protective film is formed of an inorganic insulating film and a positive photosensitive material. And an organic insulating resin having the same. 2. A semiconductor comprising an inorganic protective film and an organic protective film formed so as to cover an electrode to be connected to an external electrode on a semiconductor integrated circuit substrate, and a through hole for leading out the electrode being formed in the inorganic protective film and the organic protective film. In the method of manufacturing an integrated circuit, a step of forming the inorganic protective film on the semiconductor integrated circuit substrate; a step of forming the organic protective film having positive photosensitivity on the inorganic protective film; A step of applying a positive photosensitive resin on the film; a step of forming the through hole having a predetermined shape in the organic protective film and the photosensitive resin on the electrode by exposure and development; and Etching the inorganic protective film on the electrode to expose the electrode. 3. The method of manufacturing a semiconductor integrated circuit according to claim 2, wherein said developing is performed with a non-solvent-based alkaline aqueous solution.