JP2002064054A - Resist pattern, method for forming wiring, and electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist pattern with which a wiring pattern can be formed at a higher temperature and which has a sufficient heat resistance, and to provide a method for forming wiring using the resist pattern. SOLUTION: A first resist layer 21 formed on a substrate 20 is formed of an organic material having high solubility against a resist stripper, such as an organic solvent, etc., and a heat resistance, and a second resist layer 22 formed on the first resist layer 21 is formed of another organic material having high absorbance against light having the wavelength of exposing light and a heat resistance. Then a third resist layer 23 is formed on the second resist layer 22 of a third organic material having a high dry-etching resistance and a heat resistance. The organic material used for forming the first resist layer 21 contains polydimethyl gultalimide as a main ingredient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist pattern used for forming a fine pattern on a substrate by a lift-off method and a wiring forming method using the same. And a wiring pattern using the same.

[0002]

2. Description of the Related Art A lift-off method is widely used as one of methods for forming metal wiring on various substrates such as a semiconductor substrate, a dielectric substrate, and a pyroelectric substrate. In the lift-off method, after a predetermined resist pattern is formed on a substrate, a wiring material (metal material) is formed on the substrate by a method such as an evaporation method or a sputtering method, and then unnecessary wiring material on the resist pattern is removed. And removing the resist pattern together with the resist pattern to form a metal wiring of a desired pattern on the substrate.

When a metal wiring is formed by such a lift-off method, the cross-sectional shape is an inverted tapered shape in order to separate a wiring pattern (metal wiring) from an unnecessary wiring material on a resist pattern and to easily separate the wiring pattern. It is necessary to form a resist pattern.

Further, the resist pattern needs to have heat resistance so as not to be deformed when forming a wiring material (metal material). Furthermore, in order to improve the adhesion of the metal film to the substrate surface, a method of forming a film while heating the substrate is often used, and the resist pattern is deformed even under such heating conditions. Heat resistance that does not occur is required.

In the lift-off method, after the metal film is formed, the resist pattern is dissolved with an organic solvent or the like to remove the unnecessary metal film on the resist pattern.
It is desirable that the resist peeling property does not deteriorate even by heating during film formation.

[0006]

However, in general, it is often difficult to achieve both heat resistance and peelability of a resist. For example, as a method of improving the heat resistance of a resist, there is a UV curing method of irradiating ultraviolet rays while heating. However, this method promotes polymerization between molecules constituting the resist, and thus has improved heat resistance. However, there is a problem that the solubility in an organic solvent is reduced and the releasability is extremely reduced.

As a method of forming a resist pattern for lift-off having characteristics of heat resistance, peelability, and inverse tapered cross section, there is a method disclosed in Japanese Patent Application Laid-Open No. 2-137224. In this method, as shown in FIG. 7A, a first organic layer 11 for improving the releasability is formed on a substrate 10, and on the first organic layer 11,
A heat-resistant second organic layer 12 is formed, and an organic layer of a photoresist or an ionizing radiation resist having dry etching resistance and heat resistance (third organic layer) is formed on the second organic layer 12. 7), and the third organic layer 13 is patterned by a normal photolithography process as shown in FIG. 7 (b), and then the third organic layer 13 is formed as shown in FIG. 7 (c). Dry etching is performed using the organic layer (resist pattern) 13 as a mask, and the second organic layer 12 and the first organic layer 11, which are the lower resist, are overlaid so as to be thinner than the third organic layer 13. By etching, a resist pattern having a reverse tapered cross section is formed.

In this method, since the resist pattern is formed from an organic film pattern having better heat resistance than before, a lift-off pattern can be formed at a high temperature. Specifically, a 0.5 μm-thick polymethyl methacrylate (PMMA) is formed on the first organic layer 11, a 6 μm-thick polyimide layer is formed on the second organic layer 12, and a film is formed on the third organic layer 13. 3.0 μm thick Si
It is exemplified that a lift-off resist pattern having a three-layer structure is formed using a negative-type photoresist layer, and the organic film pattern is deformed even at a high temperature condition such that the substrate temperature becomes 350 ° C. by an evaporation method. Instead, it is possible to form a metal film pattern having a thickness of 3 μm of molybdenum.

However, in this method, the second layer, the third layer,
Although those having heat resistance are used as the organic films 12 and 13 of the first layer, the organic film 11 of the first layer is not configured to select a film having particularly heat resistance.
The heat resistance of the three-layer organic film pattern as a whole is not always sufficient. That is, in this method, as described above, it is shown that PMMA which is a thermoplastic resin is used as the first organic film 11, but in this case, the glass transition point (Tg) of PMMA is Since the temperature is 115 ° C. (fourth edition Experimental Chemistry Course Basic Operation II, p288, Maruzen Co., Ltd.), it is considered that the first organic layer 11 is deformed when heated to 350 ° C. In fact, it cannot be said that it has excellent heat resistance.

The present invention has been made in view of such circumstances, and has a resist pattern having a sufficient heat resistance capable of forming a wiring pattern at a higher temperature, and a wiring pattern using the same. It is an object of the present invention to provide a forming method and an electronic component in which wiring is formed by using such a wiring method. Another object of the present invention is to provide a resist pattern excellent in applicability to miniaturization and line width stability, a wiring forming method using the same, and an electronic component having a wiring formed by using the wiring forming method.

[0011]

In order to achieve the above object, the resist pattern of the present invention (claim 1) is formed on a substrate, has high solubility in a stripping solution such as an organic solvent, and has heat resistance. A first resist layer made of an organic material, a second resist layer formed on the first resist layer, made of an organic material having high absorbance to an exposure wavelength and having heat resistance, and A third resist layer formed of an organic material having high resistance to dry etching and heat resistance formed on the resist layer.

In the resist pattern of the present invention, the first resist layer formed on the substrate is formed of an organic material having high solubility in a stripping solution such as an organic solvent and having heat resistance, and The resist layer is formed of an organic material having high absorbance to the exposure wavelength and having heat resistance, and the third resist layer is formed of an organic material having high resistance to dry etching and having heat resistance. Since each resist layer has heat resistance, it is possible to secure sufficient heat resistance as a whole. Therefore, by using this resist pattern to form wiring under, for example, high-temperature conditions, it is possible to reliably form a fine, highly-reliable wiring having an intended line width and excellent adhesion to a substrate. Can be formed. In the present invention, "having heat resistance" means that the first, second, and third resists do not substantially deform during the film forming process (heat-resistant resistance). It is a concept that means to have.

Further, the resist pattern according to claim 2 is characterized in that the first resist layer is a layer formed using an organic material containing polydimethylglutarimide as a main component.

As a material constituting the first resist layer,
By using an organic material containing polydimethylglutarimide as a main component, it is possible to reliably form a first resist layer having high solubility in a stripping solution such as an organic solvent and excellent heat resistance. The invention can be made effective.

In the resist pattern of the present invention, the reflectivity of a portion below the third resist layer may be reduced by optimizing the thicknesses of the first resist layer and the second resist layer. It is characterized by being lowered.

By controlling the film thickness of the first resist layer and the film thickness of the second resist layer and optimizing the ratio of both film thicknesses, the reflectivity of the portion below the third resist layer is reduced. Resist, which suppresses the standing wave effect and suppresses irregular reflection from the back surface when a transparent back surface roughened substrate is used, and is excellent in miniaturization applicability and line width stability. It becomes possible to form a pattern.

Further, according to the wiring forming method of the present invention (claim 4), a first resist layer made of an organic material having high solubility in a stripping solution such as an organic solvent and having heat resistance is formed on a substrate. A step of forming a second resist layer made of an organic material having a high absorbance to an exposure wavelength and having heat resistance on the first resist layer; and forming a dry resist on the second resist layer. A step of forming a third resist layer made of an organic material having high resistance to etching and having heat resistance, and a step of forming an opening by exposing and developing the third resist layer; Forming a predetermined resist pattern by etching and removing the second resist layer and the first resist layer through the opening; It is characterized by comprising a step of forming a metal wiring on top.

The wiring forming method of the present invention (claim 4)
First made of an organic material having predetermined characteristics such as heat resistance
Forming a second resist layer made of an organic material having predetermined characteristics such as heat resistance on the first resist layer; and forming a second resist layer on the first resist layer. A step of forming a third resist layer made of an organic material having predetermined characteristics such as heat resistance, a step of exposing and developing the third resist layer to form an opening, Forming a resist pattern by etching and removing the second and first resist layers through the step of forming a metal wiring on the substrate through the resist pattern. Accordingly, it is possible to reliably form the resist patterns of the first, second, and third aspects. As a result, it is possible to improve the degree of freedom of the wiring forming conditions, and to form the wiring under a high temperature condition by the lift-off method, to have a fine, intended line width, and to have an adhesion to the substrate. It is possible to reliably form an excellent wiring. Note that as a method for forming the metal wiring, various metal film forming methods such as an evaporation method and a sputtering method can be used.

According to a fifth aspect of the present invention, in the wiring method, the resist pattern formed on the substrate optimizes the thicknesses of the first resist layer and the second resist layer. It is characterized in that the reflectance in the lower layer side portion of the layer is reduced.

By optimizing the film thickness of the first resist layer and the film thickness of the second resist layer, the reflectivity of the lower layer side of the third resist layer is reduced, and the applicability to miniaturization is improved.
When a resist pattern with excellent line width stability is formed, it is finer, having an intended line width, and
Wiring with excellent adhesion to the substrate can be reliably formed by the lift-off method.

According to a sixth aspect of the present invention, in the wiring forming method, the first resist layer is a layer formed using an organic material containing polydimethylglutarimide as a main component.

As a material constituting the first resist layer,
By using an organic material containing polydimethylglutarimide as a main component, it is possible to reliably form a first resist layer having high solubility in a stripping solution such as an organic solvent and excellent heat resistance. The invention can be made effective.

According to a seventh aspect of the present invention, in the step of forming a metal wiring on the substrate,
It is characterized in that a metal wiring is formed on a substrate by forming a metal film while heating at a temperature of not less than ° C.

In the step of forming a metal wiring on a substrate, a metal film is formed while heating the substrate to a temperature of 140 ° C. or more to form a metal wiring having excellent adhesion to the substrate and high reliability. Is possible, and the present invention can be made more effective.

The electronic component of the present invention (claim 8) may be any one of a surface acoustic wave device, a thin film magnetic head, a semiconductor device, a mask, a liquid crystal display device, a thin film circuit device using a ceramic substrate, and an optical waveguide. Electronic components,
A metal wiring is formed on a substrate by using the wiring forming method according to any one of claims 4 to 7.

According to the electronic component of the present invention, a metal wiring is formed on a substrate by using the wiring forming method according to any one of claims 4 to 7, and compared with the case where a conventional method is used. Since it is possible to provide a fine structure including wiring having an intended line width, a small and highly reliable electronic component can be provided.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described, and features thereof will be described in more detail.

[Embodiment 1] FIG. 1 is a sectional view showing the structure of a resist pattern according to an embodiment (Embodiment 1) of the present invention.

As shown in FIG. 1, the resist pattern 19 of the first embodiment is formed by a first pattern formed on the surface of a substrate 20.
Resist layer 21, second resist layer 22 formed on first resist layer 21, and second resist layer 22
And a third resist layer 23 formed thereon. The opening 2 reaching the surface of the substrate 20 is formed in the three-layer resist pattern 19.
4 are formed. Note that a metal wiring is formed on the substrate 20 through the opening 24.

Next, with reference to FIGS. 2A to 2F, a method of forming the resist pattern 19 of the present invention and a method of forming a wiring using the resist pattern 19 will be described.

First, as shown in FIG.
A first resist layer 21 having a thickness of 0.12 μm is formed thereon by spin coating. Then, the substrate 20 on which the first resist layer 21 is formed is baked at 170 ° C. for 20 minutes. For the first resist layer 21, an organic material having high solubility in an organic solvent and excellent heat resistance, such as polydimethylglutarimide (PMGI), is used. With this type of material, the resist pattern is not deformed by a heat load in a metal wiring forming process described later, and the solubility in an organic solvent is not significantly reduced.

Then, as shown in FIG. 2B, the first resist layer 21 is spin-coated to a thickness of 0.1
A 6 μm second resist layer 22 is formed. Then, the substrate 20 on which the second resist layer 22 has been formed is
Bake at 1 ° C. for 1 minute. Note that, for the second resist layer 22, an organic material having high absorbance at the exposure wavelength and good heat resistance is used. As the organic material, a suitable material can be appropriately selected and used according to the exposure wavelength. For example, when the exposure wavelength is 365 nm, XHRi-1 manufactured by Brewer Science Inc. is used.
6 has high absorbency and is suitable.

Next, as shown in FIG. 2C, the second resist layer 22 is spin-coated to a thickness of 0.3.
A 4 μm third resist layer 23 is formed. Then, the substrate 20 on which the third resist layer 23 is formed is heated at 90 ° C.
Bake under the condition of 1 minute. Note that an organic material having high resistance to dry etching and good heat resistance is used for the third resist layer 23. More specific organic materials include Fi-SP manufactured by Fujifilm Ohlin Co., Ltd.
2 and the like.

Next, the resist having the three-layer structure formed as described above is exposed and developed, and the third resist layer 23 is patterned as shown in FIG. 2D. At this time, since the second resist layer 22 absorbs the exposure wavelength, a resist pattern having a high resolution and a fine opening width can be formed. Further, a UV curing process was performed to improve the heat resistance of the resist pattern.

Next, as described above, the third register
Resist with a three-layer structure in which the layer 23 is patterned.
On the other hand, dry etching (RI
E) is applied. Thereby, the opening of the third resist layer 23 is formed.
The second resist layer 22 and the first resist
A part of the layer 21 is removed and patterning is performed. This
In this case, the third resist layer 23 has dry etching resistance.
The etching rate is very low
While the second resist layer 22 and the first resist layer
Since 21 is etched away at a normal rate, the result is
2 (e), the cross-section is an inversely tapered resist
Pattern is obtained. Note that dry etching (RI
Detailed etching conditions in the E) step are as follows:
It is. Gas used: O₂  Processing vacuum degree: 6.7 Pa RF power: 300 W Processing time: 3 minutes

Then, using the resist pattern thus formed, aluminum is deposited on the substrate 20 to form an aluminum film having a thickness of 0.2 μm. In forming the aluminum film, the substrate 20
In order to improve the adhesion of the aluminum film to the substrate, vapor deposition was performed while heating the substrate to 190 ° C. At this time, since each of the resist layers constituting the resist pattern has good heat resistance, aluminum can be evaporated without causing deformation of the resist pattern.

Thereafter, the substrate is immersed in an organic solvent to remove the resist pattern. As a result, as shown in FIG. 2F, a fine aluminum pattern 25 having good adhesion to the substrate 20 and having a desired line width and film thickness can be formed. Here, the line width is 0.3 μm.
An aluminum pattern 25 having a thickness of 0.4 μm and a thickness of 0.4 μm was formed. The aluminum pattern 2 thus formed
5 can be suitably used as an electrode of a surface acoustic wave element, for example.

The resist pattern 19 (FIG. 1) formed in the first embodiment includes
Since a material having good heat resistance is used for 22 and 23, the heat resistance of the entire three-layer resist pattern can be improved, and the first resist layer 21 can be dissolved in an organic solvent. Since an organic material having high heat resistance and good heat resistance is used, both characteristics of heat resistance and peelability can be secured.

FIGS. 3 (a), 3 (b) and 3 (c) show the results of conducting a heating test using a hot plate on the resist pattern formed by the method of the first embodiment.
3A is a resist pattern after heating at 180 ° C. for 5 minutes, FIG. 3B is a resist pattern after heating at 190 ° C. for 5 minutes, and FIG. 3C is a resist pattern after heating at 200 ° C. for 5 minutes. 5 is an SEM photograph showing each of the resist patterns after the process.

As shown in FIGS. 3A, 3B and 3C, when the resist pattern formed by the method of the first embodiment is heated to 200 ° C., the first resist layer Is deformed, but when heated to 180 ° C. and 190 ° C., no deformation occurs not only in the first resist layer but also in the second and third resist layers.

In the first embodiment, UV curing is performed after patterning of the third resist layer.
Depending on the conditions of the dry etching process using oxygen plasma, the second resist layer and the third resist layer
An irradiation effect and a heating effect may be provided, and as a result, an effect similar to the UV curing process may be provided. In such a case, the above-described UV curing process becomes unnecessary.

[Second Embodiment] In the second embodiment, the first
A case will be described in which the film thicknesses of the resist layer and the second resist layer are optimized to reduce the reflectivity of a portion below the third resist layer.

In the second embodiment, the film thicknesses of the first resist layer and the second resist layer are controlled (optimized) so as to lower the reflectivity of a portion below the third resist layer. I did it. The other configuration is the same as that of the first embodiment, and the description is omitted here to avoid duplication.

In order to control and optimize the film thicknesses of the first resist layer and the second resist layer to reduce the reflectivity of a portion below the third resist layer, first, the first resist layer and the second resist layer are formed. The relationship between the thickness of the second resist layer and the reflectance (reflected light intensity / incident light intensity) was examined. The distribution of the reflectance
FIG. 4 shows the results of a simulation using Prolith 2 (Finley). In FIG. 4, the numerical values drawn by the lead lines for each region are as follows:
It shows the value of the reflectance (the intensity of the reflected light / the intensity of the incident light). Further, the “reflectance” here is not the reflectivity when the wafer is irradiated with light after forming all of the first to third resist layers, but the lower part of the lower part of the third resist layer. Means reflectivity.

The simulation conditions for the reflectance are as follows. (1) Second resist layer: n = 1.82, k = 0.36 (where n is the real part of the complex refractive index and k is the imaginary part of the complex refractive index) Film thickness: 100 to 300 nm (2) First resist layer: n = 1.90, k = 0 Thickness: 100-200 nm (3) Third resist layer: PFI-37 (Sumitomo Chemical Co., Ltd.)
(4) Pre-bake conditions: 90 ° C., 60 seconds (5) Exposure conditions: NA = 0.6, σ = 0.7, λ = 365n
m (6) Pattern: 0.5 μm L / S (line width 0.5 μm, space width 0.5 μm)

As shown in FIG. 4, the reflectance decreases as the thickness of the second resist layer increases. This is due to the fact that the characteristics of the second resist layer having high light absorption are exhibited.

When the film thickness of the second resist layer is changed while keeping the film thickness of the first resist layer constant, the reflectance changes sinusoidally, and the film thickness of the second resist layer is changed. Even when the film thickness of the first resist layer is changed to be constant, the reflectance changes sinusoidally. As described above, when the film thickness of the first and second resist layers is changed, the reflectance becomes 2
It turns out that it changes dimensionally. The reason why the reflectivity changes in a sinusoidal manner is due to interference between the incidence and reflection of exposure light.

Next, the relationship between the reflectance and the cross-sectional shape of the third resist layer was examined. FIGS. 5A to 5D show latent images (relative density of photosensitizer (1 = completely exposed, 0 = unexposed)) of the cross section of the third resist layer before exposure before baking (PEB) after exposure. It is shown. 5A to 5D, the horizontal axis indicates the position in the horizontal direction of the resist pattern (the region of -250 to 250 nm is an exposure area), and the vertical axis indicates the vertical direction (thickness direction) of the third resist layer. Indicates the position. In addition, FIG.
In (d), for each area, the numerical value drawn out by a lead line indicates the value of the relative concentration of the photosensitive agent. The thickness of the first resist layer in FIGS. 5A to 5D is determined by the combination of the positions indicated by ●, ▲, Δ, and ▼ in FIG. Fixed at 150nm,
The thickness of the first resist layer is set to 200, 210, 2
20 and 230 nm. 5A to 5D, when the thickness of the first resist layer is set to 210 nm (FIG. 5B) or 220 nm (FIG. 5C), the cross section of the third resist layer is reduced. It can be seen that the tendency to form a wave is suppressed.

Based on the above-described simulation of the reflectance distribution, the thickness ratio of the first and second resist layers is optimized by changing the thickness of the first resist layer as described below. After forming a third resist film in a state where the reflectivity was reduced, exposure and development were performed to pattern the third resist layer.

(1) First, a polydimethylglutarimide (PMGI) layer is applied by spin coating,
The first resist layer having a thickness of 205 nm, 215 nm, 225 nm, and 235 nm after baking was formed. (2) Then, on this first resist layer, Brewe
XHRi-16 manufactured by rScience was applied by spin coating and baked at 130 ° C. to form a second resist layer having a thickness of 150 nm after baking. (3) Then, on the second resist layer, Fi-SP2 manufactured by Fujifilm Ohlin Co., Ltd. is applied by spin coating,
By baking at 90 ° C., the film thickness after baking becomes 31
A third resist layer of 5 nm was formed. (4) The obtained three-layer resist was exposed to i-line (wavelength = 365 nm) of a high-pressure mercury lamp and developed to obtain a resist pattern.

FIG. 6 shows an SEM cross-sectional image of the resist (third resist layer) thus patterned.
(a) to (d) show. 6A shows the first resist layer having a thickness of 205 nm, FIG. 6B shows the first resist layer having a thickness of 215 nm, and FIG. 6C shows the first resist layer. FIG. 6D shows that the first resist layer has a thickness of 225 nm.
Each of the cross-sectional images at 35 nm is shown. FIG.
From (a) to (d), when the thickness of the first resist layer is set to 215 nm (FIG. 6B), the tendency of the processed side surface of the resist to have a wavy shape is effectively suppressed. You can see that.

(5) Then, dry etching using oxygen plasma is performed in the same manner as in the first embodiment.
After exposing the substrate surface, an aluminum pattern was deposited while heating to 70 ° C. (6) Then, the substrate is immersed in an organic solvent to peel off the resist pattern, thereby obtaining a 0.25 μm L / S, 0.2
An Al pattern having a thickness of 5 μm was formed. In the case of the method of Embodiment 1, the miniaturization limit of the resist pattern is 0.
Although it was about 30 μm, the method according to the second embodiment could improve the miniaturization limit of the resist pattern to 0.25 μm.

In the first and second embodiments, a vapor deposition method is used as a method for forming a metal film. However, a similar effect can be obtained when a metal film is formed by a sputtering method or a CVD method. It has been confirmed that

The present invention is not limited to the first and second embodiments in other respects, and various applications and modifications can be made within the scope of the invention.

[0055]

As described above, the resist pattern of the present invention (Claim 1) has a high solubility in a first resist layer formed on a substrate in a stripping solution such as an organic solvent.
And the second resist layer is formed of an organic material having high absorbance to the exposure wavelength and having heat resistance, and the third resist layer is formed by dry etching. Since the resist layer is formed of an organic material having high resistance to heat and having heat resistance, each of the resist layers has heat resistance, so that sufficient heat resistance can be secured as a whole.
Therefore, using this resist pattern, for example, by forming wiring under high-temperature conditions, it is possible to obtain a highly reliable wiring that is fine, has an intended line width, and has excellent adhesion to a substrate. It is possible to form it reliably.

Further, when an organic material containing polydimethylglutarimide as a main component is used as a material for forming the first resist layer as in the resist pattern according to the second aspect, the solubility in a stripping solution such as an organic solvent. Therefore, it is possible to reliably form the first resist layer having high heat resistance and high heat resistance, and the present invention can be effectively demonstrated.

Further, by controlling the film thickness of the first resist layer and the film thickness of the second resist layer as in the resist pattern of claim 3, the relationship between the two is optimized. It is possible to lower the reflectance of the lower layer side portion than the third resist layer, and to suppress the standing wave effect,
It is possible to form a resist pattern having excellent applicability to miniaturization and excellent line width stability by suppressing irregular reflection from the back surface when a transparent back surface roughened substrate is used.

Further, according to the wiring forming method of the present invention (claim 4), a step of forming a first resist layer made of an organic material having predetermined characteristics such as heat resistance on a substrate; Forming a second resist layer made of an organic material having predetermined characteristics such as heat resistance on the layer;
Forming a third resist layer made of an organic material having predetermined characteristics such as heat resistance on the resist layer, and exposing and developing the third resist layer to form an opening. Etching the second and first resist layers through the opening to form a resist pattern;
Forming a metal wiring on the substrate via the resist pattern. By performing this method, the resist pattern of the first, second, and third aspects can be surely formed. Therefore, it is possible to improve the degree of freedom of the wiring forming conditions, and to form the wiring under a high temperature condition by the lift-off method, to have a fine, intended line width, and to improve the adhesion to the substrate. Excellent wiring can be reliably formed.

According to a fifth aspect of the present invention, there is provided
By controlling and optimizing the film thickness of the first resist layer and the film thickness of the second resist layer, the reflectivity of the lower layer side portion below the third resist layer is reduced, When a resist pattern having excellent line width stability is formed, a finer wiring having an intended line width and excellent adhesion to a substrate is surely formed by a lift-off method. Will be able to

Further, according to the wiring forming method of claim 6,
When an organic material containing polydimethylglutarimide as a main component is used as a material for forming the first resist layer,
The first resist layer having high solubility in a stripping solution such as an organic solvent and excellent in heat resistance can be reliably formed, and the present invention can be effectively demonstrated.

Further, as in the wiring forming method of claim 7,
In the step of forming metal wiring on the substrate,
When the metal film is formed while being heated to 0 ° C. or higher, it is possible to form a highly reliable metal wiring with excellent adhesion to the substrate.

In the electronic component of the present invention (claim 8), metal wiring is formed on the substrate by using the wiring forming method according to any one of claims 4 to 7, and the conventional method is used. Compared with the case where the electronic component is used, it is possible to provide a structure having finer wiring having an intended line width, so that a small and highly reliable electronic component can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration of a resist pattern according to an embodiment (Embodiment 1) of the present invention.

FIGS. 2A to 2F are process diagrams showing a method for forming a resist pattern and a method for forming a wiring according to the first embodiment.

FIGS. 3A to 3C are SEM photographs showing heat resistance of the resist pattern of the first embodiment.

FIG. 4 is a diagram showing the relationship between the thicknesses of first and second resist layers and the reflectance obtained by simulating the distribution of the reflectance.

FIG. 5: Baking of third resist layer after exposure (PEB)
FIG. 7 is a diagram illustrating a previous latent image (a state of relative density of a photosensitive agent (1 = completely exposed, 0 = unexposed)).

FIG. 6 is a diagram showing a cross-sectional image by SEM of a patterned resist (third resist layer).

FIGS. 7A to 7C are process diagrams showing a conventional method for forming a resist pattern.

[Explanation of symbols]

 Reference Signs List 19 resist pattern 20 substrate 21 first resist layer 22 second resist layer 23 third resist layer 24 opening 25 aluminum pattern

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/3205 H05K 3/06 F 5F046 H05K 3/02 H01L 21/30 573 // H05K 3/06 21 / 88 GF term (reference) 2H092 MA15 MA18 MA19 MA37 NA25 PA01 2H096 AA27 BA01 HA15 HA23 KA19 KA21 KA25 LA13 LA30 5C094 AA03 AA31 AA32 BA43 EA04 EB02 5E339 BE20 CD01 CE00 CF00 CF16 CF17 FF03 5F063 PP19 NA08

Claims (8)

[Claims] A first resist layer formed on a substrate and made of an organic material having high solubility in a stripping solution such as an organic solvent and having heat resistance; and a first resist layer formed on the first resist layer and exposing to light. A second resist layer made of an organic material having high absorbance at a wavelength and having heat resistance; and an organic material formed on the second resist layer, having high resistance to dry etching and having heat resistance. A resist pattern comprising: a third resist layer. 2. The resist pattern according to claim 1, wherein the first resist layer is a layer formed using an organic material containing polydimethylglutarimide as a main component. 3. The method according to claim 1, wherein the film thickness of the first resist layer and the second resist layer is optimized to reduce the reflectivity of a portion below the third resist layer. The resist pattern according to claim 1. 4. A step of forming a first resist layer made of an organic material having high solubility in a stripping solution such as an organic solvent and having heat resistance on a substrate, and exposing the first resist layer to light on the first resist layer. A step of forming a second resist layer made of an organic material having high absorbance at a wavelength and having heat resistance; and an organic material having high resistance to dry etching and having heat resistance on the second resist layer. The third consisting of
Forming an opening by performing exposure and development on the third resist layer; and forming the second resist layer and the first resist through the opening. A wiring forming method, comprising: a step of forming a predetermined resist pattern by etching and removing a layer; and a step of forming a metal wiring on a substrate through the resist pattern. 5. The method according to claim 1, wherein the resist pattern formed on the substrate optimizes the thicknesses of the first resist layer and the second resist layer so that the reflectivity of a portion below the third resist layer is reduced. 5. The method according to claim 4, wherein the wiring is reduced. 6. The wiring forming method according to claim 4, wherein said first resist layer is a layer formed using an organic material containing polydimethylglutarimide as a main component. 7. The method according to claim 1, wherein, in the step of forming a metal wiring on the substrate, the metal wiring is formed on the substrate by forming a metal film while heating the substrate to 140 ° C. or higher. 7. The wiring forming method according to any one of 4 to 6. 8. An electronic component selected from the group consisting of a surface acoustic wave device, a thin film magnetic head, a semiconductor device, a mask, a liquid crystal display device, a thin film circuit device using a ceramic substrate, and an optical waveguide. An electronic component, wherein a metal wiring is formed by using the wiring forming method according to claim 4.