JPH03268427A - Formation of organic resin film pattern and manufacture of multilayered wiring board - Google Patents

Abstract

PURPOSE:To simplify the process and to enable the manufacture of multilayered wiring structures with high yield and high reliability by using an alkali development type organic silicone resist as the resist layer, and oxygen/halogenated carbonic gas as the etching gas. CONSTITUTION:An organic resin film 2 of 5-100mum thickness is used in forming organic resin film patterns: an alkali development type organic silicone resist is used as a resist film 3, and oxygen gas or oxygen/halogenated carbonic gas as a dry-etching gas. That is, a material which has sensitivity to light and resistance to oxygen plasma is used to make a photoirradiated pattern-forming member and a dry-etching mask member from one film. Therefore, it is not only unnecessary to use two layers-inorganic film and resist, but also possible to easily remove this resist 4 having both functions of light sensitivity and plasma resistance. This way enables the high-precision formation of organic resin film patterns and the manufacture of multilayered wiring structures by a relatively simple process.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for patterning an organic resin film and a method for manufacturing a multilayer wiring board. In particular, in the manufacture of thin-film multilayer substrates in which thick organic resin films are used as insulating films for computers, thin-film magnetic disks, thin-film heads, hybrid integrated circuits, etc., methods for processing organic resin films with high precision and high aspect ratios. The present invention also relates to a method for manufacturing a multilayer wiring board using the same.

[Conventional technology]

2. Description of the Related Art In recent years, with the remarkable improvement in the density of semiconductor devices and the like, it has become desirable to form patterns with extremely small line widths with high precision. Further, in electronic circuits such as computers, thin-film magnetic disks, thin-film heads, and hybrid integrated circuits, thin-film circuits are used in which organic films, which are thicker than semiconductor elements, are used as interlayer insulating films and insulating protective films.

By the way, in order to provide windows and grooves between the conductor layers at predetermined positions of this organic film, the organic film at predetermined positions is removed by wet etching using a photolithography technique well known in boat fishing.

In other words, in the production of conventional thin film multilayer substrates, first,
An insulating layer is formed by coating an organic resin film on the entire surface of the substrate, a photoresist is coated on this, a desired resist pattern is formed by exposure, an I31 image, and rinsing, and the organic film is etched by wet etching using this as a mask. Windows and grooves were formed in the area. Thereafter, a wiring metal layer was formed, the resist was removed, and a predetermined wiring pattern was formed. However, since wet etching is isotropic etching, it has high resolution and high aspect ratio (height 7 width).
The larger the value, the steeper it is. ), trial etching was desired. Firstly, litching is performed using oxygen plasma, but since general-purpose resists do not have resistance to trietching, methods using resist and inorganic films that can be used as mask materials have been investigated.

However, the method of using an inorganic film and a resist as an etching mask requires a long process, and simplification of the process is strongly desired for mass production. In particular, when the organic resin film becomes thicker, a thicker inorganic film is required, and it takes a longer time to form and peel it off.

[Problem to be solved by the invention]

An object of the present invention is to provide a method for forming a pattern of an organic resin film and a method for manufacturing a multilayer wiring board, which eliminates the drawbacks of the prior art and is simple and has excellent reliability, yield, etc.
be.

[Means to solve the problem]

In order to achieve the above object, the present inventors investigated various materials and processes regarding the method of patterning organic resin films and the method of manufacturing multilayer wiring boards. We have discovered that it is sufficient to form a pattern using a material that has the following properties. That is, in the present invention, a pattern forming material by light irradiation and a dry etching mask material are formed in one film.

It is no longer necessary to use two layers of an inorganic film and a resist as in the past, and as a result, the process is simplified. Further, the resist having both the functions of photosensitivity and plasma resistance is easy to remove, and can be removed using a general-purpose resist stripping solution, an alkaline developer, or the like.

The photosensitive material with excellent oxygen plasma resistance used in the present invention is an alkali-developable organosilicon yarn material, especially an organic group in which all or part of the side chain has a phenolic hydroxyl group. It is desirable that the main components are an alkali-soluble polyorganosilsesquioxane polymer and a 1,2-naphthoquinonediazide photosensitive dissolution inhibitor. These are used by coating them in a state dissolved in an organic solvent such as ethyl cellosolve acetate.

Etching of the organic resin film is usually carried out using oxygen gas or a mixed gas of oxygen and halogenated carbon. There is no problem when the organic resin film to be processed is relatively thin, but as the organic resin film becomes thicker, residue (scum) may be generated on the substrate after etching. In order to eliminate this problem, the inventor conducted various studies and found that it is sufficient to perform light etching with a halide carbon gas such as CF4 before or after etching with oxygen gas or a mixed gas of oxygen and halide carbon. .

Of course, light etching may be performed using a halogenated carbon gas such as CF4 before or after etching using oxygen gas or a mixed gas of oxygen and halogenated carbon.

Furthermore, although it is normally desired to remove the resist in a wet manner, dry removal is also possible. In particular, it is effective to perform post-exposure and remove the resist.

In this way, by providing photosensitivity and oxygen plasma resistance in one layer, an organic resin film pattern can be formed with a simple process, and a multilayer wiring board can also be manufactured.

Hereinafter, an outline of the present invention will be explained according to the configuration illustrated in FIG.

In the organic resin film pattern forming method and multilayer wiring board manufacturing method of the present invention, an organic resin film 2 is first formed on a substrate (insulating substrate, wiring board, or multilayer wiring board) 1 (see Fig. 1(b). )). This formation method is usually performed by spin coating a polyimide solution (PIQ, manufactured by Hitachi Chemical Co., Ltd., etc.). Next, a resist layer 3 having photosensitivity and oxygen plasma resistance is formed thereon (FIG. 1(C)).

Thereafter, the resist JtlJ3 is patterned by a first lithography technique, and using this resist pattern 4 as a mask, the organic resin film is dry etched with oxygen plasma or the like (FIG. 1(d)).

After opening windows and grooves 7 in the organic resin film 2 in this way (Fig. 1 (e)), the rinsing] is removed wet or dry (Fig. 1 (f)), and then the pattern A wiring conductor 6 is formed on the coated organic resin film 5 (FIG. 1(g)) to obtain a multilayer wiring structure. The above steps are repeated as necessary.

To embody the present invention, the following materials and processes may be used.

The organic resin film may be a heat-resistant organic resin film such as a polyimide resin material, a polystyrene material, a material obtained by heart-baking a novolac-based positive photoresist, or a material obtained by hard-baking a polyvinylphenol-based negative photoresist. Preferably, it is a molecular material;
It is formed by spin coating or the like. The film thickness is 5 to 100 μm, and if the film cannot be formed in one cycle, the steps of coating, drying, and curing are repeated.

As the resist material, for example, organic silicon thread positive photoresist (Hitachi Chemical $2RU-1600P)
etc.) is applied, dried and formed.

Usually, it is used with a film thickness of about 0.5 to 10 μm. This patterning is performed by well-known photolithography. That is, a resist pattern is obtained by exposing to light in a desired pattern using a contact aligner or a projection aligner, developing and rinsing. Since organosilicon thread positive photoresists are used in a single layer,
It is convenient for processing thick organic resin films because it does not cause cracks or the like even when thickened, and thick films can be photosensitized.

Etching is not particularly limited, but a parallel plate dry etching device, a microwave etching device, etc. can be used. As an etching gas,
Oxygen gas or a mixed gas of oxygen and halogenated carbon is used, and if light etching is performed with a halogenated carbon gas such as CF4 before or after etching, there will be no residue after etching, which is even better.

Also, resist removal is usually done after post-exposure.

It is preferable to perform the removal by immersion in an alkaline developer or resist stripping solution, but dry removal may also be used. As the wiring material, metal materials such as copper, aluminum, and nickel are used.

Although the VA manufacturing method of the present invention has been explained above using actual materials and processes, it is not limited thereto.

[Effect]

In the present invention, pattern formation by light irradiation and dry etching can be performed in one film by using an alkaline-developable organosilicon resist as the resist layer and using oxygen gas or oxygen/halogenated carbon gas as the etching gas. This makes it possible to simplify the process. especially.

Since a single layer of photoresist with excellent oxygen plasma resistance is used, it can be exposed thickly, does not contain cranks, etc., and can be easily removed, which is advantageous when processing thick organic tung fat films. Furthermore, from a process standpoint, it is possible to manufacture a multilayer wiring structure with high yield and high reliability as well as mass production. It is also an excellent method from the viewpoint of increasing resolution.

〔Example〕

-Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 A polyimide resin which is an organic resin film (in this example, Hitachi Chemical Jl.
1% PIQ (trade name) was applied by spin coating. The curing was performed under the conditions of 200°C/30 minutes + 350°C/30 minutes. This operation was repeated four times to obtain a polyimide layer 2 with a thickness of about 20 μm.

Next, as a resist material with excellent oxygen plasma resistance,
After spin coating using an organosilicon thread positive photoresist (Rt>1600P manufactured by Tachi Kasei Co., Ltd.) containing alkali-soluble ladder silicone as a matrix polymer,
Resist wl3 by pre-baking at ℃/30 minutes
was formed.

The organosilicon resist used here is an organic alkali-soluble polyorganosilsesquioxane polymer with all or part of its side chains having phenolic hydroxyl groups, and a 1,2-naphthoquinonediazide photosensitive dissolution inhibitor. It consists of a drug. Note that the film thickness in this example is approximately 5 μm. Subsequently, this resist was patterned using a conventional photolithography technique.

That is, the resist was irradiated with approximately 2000 mJ/cJ using a 1/1 projection aligner, developed for 2 minutes using an alkaline developer (0.66 wt, %-NMD-3), and rinsed with running water. I got the pattern.

Subsequently, in this example, the sample was placed in a parallel plate dry etching device, and first etched with CF4 gas for 5 minutes, and then the exposed organic resin film was etched with oxygen plasma for 3 hours to form a 15 μm window 7 ( A through hole) was formed. (Oxygen plasma etching conditions: oxygen pressure, 5Pa
; flowing blue, 30 sc cm; power, soo'w; bias voltage, -110 V) At this time, the through holes in the organic resin film are steep, which is extremely convenient from the viewpoint of miniaturization. Note that the cross-sectional shape of the through hole can be controlled by controlling the dry etching conditions.

Next, before forming the second layer wiring conductor 6, the resist is wet-stripped 111 (for example, using stripping liquid 5-10 manufactured by Tokyo Ohka Kogyo Co., Ltd.).
(immersed in a 60°C solution for 10 minutes).

Thereafter, a wiring conductor 6 was formed to obtain a two-layer wiring structure.

In addition, multilayer wiring 41! ! When making 12 bodies, the above steps were repeated in sequence.

In this way, it is possible to pattern an organic resin film and manufacture a multilayer wiring structure with high precision using a relatively simple process using ordinary photolithography technology.

Examples 2 to 10 Patterning of an organic resin film and production of a multilayer wiring structure were carried out in the same manner as in Example 1 under the conditions shown in Table 1.

In either case, it was possible to form a pattern of an organic resin film with high precision and to perform kJ construction of a multilayer wiring structure with a simple process, and it was an excellent method.

Margins below [Effects of the Invention] As is clear from the above description, by using the method of the present invention, a multilayer wiring structure in which the organic resin film is an Illin film can be manufactured in an extremely simple manner. Furthermore, since the etching rate ratio of the resist layer and the organic resin film to oxygen plasma is large, it is possible to form a pattern having a high aspect ratio. In particular, according to the present invention, it is possible to form a particularly thick organic resin film pattern and to construct a multilayer wiring board using the pattern in a simple process, which has the advantage of being excellent in mass production and cost reduction. Furthermore, since there is no residue after etching, improved reliability and yield can be expected.

It should be noted that, as a matter of course, the present invention is not limited to the above-described embodiments or the illustrated structural examples.

[Brief explanation of drawings]

FIG. 1 is a process diagram for explaining the present invention in detail,
This can be applied in the embodiments of the present invention. 1... Substrate, 2... Organic resin film (insulating film), 3...
- Resist material with excellent plasma resistance, 4... Patterned resist material, 5... Patterned organic resin film, 6... Wiring conductor, 7... Through hole.

Claims (1)

[Claims] 1. An organic resin film is provided on a substrate, a resist layer having resistance to oxygen plasma etching is formed on the organic resin film, and a desired portion of this resist layer is exposed to light; In a method of forming a pattern of an organic resin film by developing and rinsing and removing the exposed organic resin film by dry etching, an organic resin film with a thickness of 5 to 100 μm is used, and an alkali-developable organic silicon film is used as a resist layer. A method for forming a pattern on an organic resin film, characterized in that a resist is used, and oxygen gas or oxygen/halogenated carbon gas is used as a dry etching gas. 2. The alkali-developable organosilicon resist includes an alkali-soluble polyorganosilsesquioxane polymer in which all or part of the side chains are organic groups having a phenolic hydroxyl group, and a 1,2-naphthoquinonediazide photosensitive resist. 2. The method for forming a pattern of an organic resin film according to claim 1, which comprises a dissolution inhibitor. 3. The organic resin film is made of a polyimide resin material, a polystyrene material, a hard-baked novolak positive photoresist, or a hard-baked polyvinylphenol negative photoresist. A method for forming patterns on organic resin films. 4. The organic resin according to claim 1, wherein in the dry etching, light etching is performed using a halogenated carbon gas before or after etching using oxygen gas or oxygen/halogenated carbon gas, or before and after etching using oxygen gas or oxygen/halogenated carbon gas. Membrane patterning method. 5. The method for patterning an organic resin film according to claim 1, wherein the substrate is a wiring board or a multilayer wiring board. 6. forming an organic resin film on the substrate on which the first layer wiring conductor is formed, and forming a resist layer having resistance to oxygen plasma etching on this film;
Desired areas of this resist layer are exposed to light, developed,
From the step of rinsing to partially expose the organic resin film, the step of removing the exposed organic resin film by dry etching, the step of removing the resist layer, and the step of forming a second layer wiring conductor in a predetermined pattern. In the method for manufacturing a multilayer wiring board, an organic resin film with a thickness of 5 to 100 μm is used, an alkali-developed organosilicon resist is used as the resist layer, and oxygen gas or oxygen/halogenated carbon gas is used as the dry etching gas. A method for manufacturing a multilayer wiring board, characterized by: 7. The alkali-developable organosilicon resist includes an alkali-soluble polyorganosilsesquioxane polymer in which all or part of the side chains are organic groups having a phenolic hydroxyl group, and a 1,2-naphthoquinonediazide photosensitive material. 7. The method for manufacturing a multilayer wiring board according to claim 6, which comprises a dissolution inhibitor. 8. The organic resin film is made of a polyimide resin material, a polystyrene material, a hard-baked novolac positive photoresist, or a hard-baked polyvinylphenol negative photoresist. A method for manufacturing a multilayer wiring board. 9. The multilayer wiring board according to claim 6, wherein in the dry etching, light etching is performed using a halogenated carbon gas before, after, or before and after etching using oxygen gas or oxygen/halogenated carbon gas. manufacturing method. 10. The method of manufacturing a multilayer wiring board according to claim 6, wherein in the resist removal, wet removal is performed after post-exposure. 11. The method for manufacturing a multilayer wiring board according to claim 6, wherein the substrate is a wiring board or a multilayer wiring board.