JPH10193162A - Method for removing contaminated material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perfectly and surely remove a contaminated material by applying an energy transdusing medium on the contaminated material (by-product) stuck to a base material having water repellency or a base material subjected to water repellent treatment and irradiating it with a laser beam. SOLUTION: In a base material 4 formed with a water repellent layer 5, a liquid 7, which contains a surface active agent as an energy transfusing medium, is coated on the surface stuck with a contaminated material 6 (by-product), a liquid 7 containing a surface active agent is irradiated with a laser beam, which is emitted from a YAG laser 1 through a SHG 2/ filter 3 and has a wave length having selective absorbability to be absorbed in the liquid 7, the energy transdusing medium is instantly evaporated or transdused to a kinetic energy, thus, the contaminated material is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser or the like for irradiating a laser beam onto a resin or the like to perform processing, and to remove contaminants (by-products) attached to the surface of the resin or the like by laser processing. It relates to a method of removing by irradiation.

[0002]

2. Description of the Related Art When a resin is irradiated with a laser beam such as a KrF excimer laser to perform ablation processing, film formation processing, or other processing, an energy larger than an intermolecular dissociation energy of molecules constituting a resin material. With the excimer laser light with, the molecules of the resin material are directly cut off and decomposed and removed,
At this time, the decomposed and removed carbon, carbide, and the like are scattered as fine fragments, and the fine fragments fall and accumulate on the resin surface and adhere thereto. Such by-products adhering to the surface of the resin contaminate the surface, which is not preferable.

[0003] Therefore, such contaminants (by-products)
Conventionally, various methods have been proposed for removing carbon from the surface of a resin or the like. Among them, the following method has been proposed as a method for removing contaminants attached to the surface of a base material such as a resin using a laser beam.

[0004] 1. A method of directly irradiating a contaminant with a laser beam having absorptivity and removing the contaminant (Japanese Patent Laid-Open No. 5-42
385).

[0005] 2. A layer of water is provided between the contaminant and the surface of the substrate on which the contaminant is attached, and the layer of water absorbs the energy of the laser beam, and is converted by kinetic energy or explosive evaporation of the layer of water. A method for flying contaminants (US Pat. No. 4,987,286).

[0006]

However, in the above prior art, in the former prior art, since there is no energy conversion medium such as water, the power to remove contaminants is weak and very fine. Only the pollutants can be removed, and in the latter prior art, since water is used as an energy conversion medium,
The removal effect is significantly improved compared to the former. However, on a substrate having water repellency or a substrate having a surface subjected to a water repellent treatment, water is repelled, and water may not function satisfactorily as an energy conversion medium.

The present invention has been made in view of the above-mentioned unsolved problems of the prior art, and is directed to applying a liquid containing a surfactant as an energy conversion medium to a substrate to which contaminants are adhered. Contaminant removal method that can completely and reliably remove contaminants even on a substrate having water repellency or a substrate having a surface subjected to water repellency treatment by irradiating the substrate with laser light. The purpose is to provide.

[0008]

In order to achieve the above object, a method for removing contaminants according to the present invention comprises applying an energy conversion medium to a substrate to which contaminants are adhered, and irradiating the medium with a laser beam. A method for removing contaminants by instantaneously evaporating an energy conversion medium or converting light energy into kinetic energy, wherein a liquid containing a surfactant is used as the energy conversion medium. .

Further, the method for removing contaminants of the present invention comprises:
The liquid containing a surfactant is preferably one that absorbs laser light, and is particularly suitable when the substrate is a material having water repellency or a material whose surface has been subjected to water repellency treatment.

[0010]

According to the present invention, a substrate such as a resin to which a contaminant (by-product) adheres to the surface by ablation, film formation, or other processing in which a substrate such as a resin is irradiated with a laser beam for processing. By applying a liquid containing a surfactant as an energy conversion medium and irradiating it with laser light of a wavelength having selective absorption, the energy conversion medium is instantaneously evaporated or the energy of the laser light is converted into kinetic energy. In order to remove contaminants, even if the substrate has a water-repellent or water-repellent treatment, a liquid containing a surfactant as an energy conversion medium, It completely covers the contaminants without being repelled on the water-repellent surface and works effectively because it penetrates between the contaminants and the water-repellent surface to completely and reliably remove the contaminants (by-products). It is those that can be.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 (a) and 1 (b) are illustrations for explaining the effect of a liquid as an energy conversion medium on contaminants adhering to a water-repellent substrate, and FIG. FIG. 1 is a configuration diagram schematically showing an example of an embodiment of a method for removing contaminants according to the present invention.

In the method for removing contaminants according to the present invention, a surfactant is used as an energy conversion medium for removing contaminants attached to a water-repellent substrate or a substrate having a surface subjected to water-repellent treatment. The method is characterized in that a liquid containing a surfactant is used. The effect of a liquid containing a surfactant on contaminants will be described with reference to FIG.

In FIGS. 1A and 1B, 11
Denotes a substrate subjected to a water-repellent treatment, and 12 denotes a contaminant adhered to the surface of the substrate. A liquid 13 containing no surfactant is used as an energy conversion medium so as to cover the contaminant 12.
When the liquid 1 is applied, as shown in FIG.
3 is repelled on the water-repellent surface, and the substrate 11 and the contaminant 1
Does not penetrate well between the two. Therefore, even if this is irradiated with a laser beam, it is not possible to obtain enough energy to remove the contaminant 12. On the other hand, when the liquid 14 containing a surfactant is applied as an energy conversion medium,
As shown in FIG. 1B, due to the action of the surfactant contained in the liquid 14, the liquid 14 exhibits good wettability without being repelled on the water-repellent surface, and completely covers the contaminants. And penetrates well between contaminants and water repellent surfaces. Therefore, when a laser beam, which will be described later, is irradiated, the liquid 14 that completely covers the contaminant and penetrates between the contaminant and the water-repellent surface can generate enough energy to completely remove the contaminant.

As described above, even if a contaminant adheres to a water-repellent substrate or a substrate whose surface has been subjected to a water-repellent treatment, a liquid containing a surfactant is applied thereto as an energy conversion medium. Therefore, the energy conversion medium can completely cover the contaminant and penetrates well between the contaminant and the water-repellent surface. The contaminants can be completely removed by the kinetic energy converted by absorbing or by instantaneous evaporation.

Next, an embodiment of the method for removing contaminants according to the present invention will be described with reference to FIG. In FIG. 2, 1 is Q-
Switch YAG laser, 2 is second harmonic generator SHG
(Second Harmonic Generator), 3 is a filter (Optical Filter). With this configuration, the laser light oscillated from the Q-switch YAG laser 1
The HG 2 forms a mixed light of the fundamental wave and its harmonic wave, and further cuts the fundamental wave by the filter 3 to extract only the harmonic wave.
To remove the contaminant 6. Then, the contaminants 6 on the substrate 4 on which the water-repellent layer 5 is formed
Is coated with a liquid 7 containing a surfactant as an energy conversion medium.

Here, the substrate 4 is a polyethersulfone film having a water-repellent layer 5 formed on the surface thereof, and is subjected to fine processing by ablation using a KrF excimer laser. The generated by-products (contaminants) 6 adhere to the water-repellent layer 5. The adhesion of the by-product (contaminant) 6 of this ablation processing can be confirmed with a metallographic microscope. Liquid (for example, black ink) 7 containing a surfactant so as to cover this by-product (contaminant) 6
Is applied. Due to the action of the surfactant, the liquid 7 containing the surfactant exhibits good wettability without being repelled on the water-repellent layer 5, and can completely cover the contaminant 6. 6 and the water-repellent layer 5. Although the black ink is illustrated as the liquid 7, the color of the liquid is desirably black, which easily absorbs light, but other colors may be used.

As described above, the by-product (contaminant) 6 adheres to the polyethersulfone film substrate 4 to which black ink is applied as a liquid 7 containing a surfactant. Irradiation of 1 to 10 pulses of a harmonic of the laser light emitted from the filter 3 is performed. At this time, the irradiated harmonic (λ = 532 nm) has an energy density of 3.3 mJ.
/ Pulss · cm ² , and the harmonic wave incident on the polyethersulfone film 4 is a laser beam having a wavelength not absorbed by the polyethersulfone, but absorbed by the liquid 7 containing a surfactant. There is a laser beam of a wavelength having a certain selective absorption. Therefore, the liquid 7 containing the surfactant functions as an energy conversion medium, and the by-product 6 can be removed by absorbing the laser beam and evaporating instantaneously. When the state of the by-product (contaminant) whose adhesion was confirmed in advance by the metallographic microscope was observed again with the metallographic microscope, it was confirmed that the by-product (contaminant) 6 was completely removed.

As described above, a substrate such as a resin having water repellency or a resin subjected to water repellency treatment is subjected to fine processing such as ablation, film formation, or other processing by irradiation with excimer laser light. A liquid containing a surfactant as an energy conversion medium is applied to the contaminants (by-products) attached to the surface, and the liquid is irradiated with a laser beam having a wavelength of selective absorption, thereby converting the energy. The medium can be evaporated instantaneously, or the energy of the laser light can be converted to kinetic energy and removed with contaminants. Thus, even if the substrate has water repellency or has been subjected to a water repellent treatment,
The liquid containing a surfactant as an energy conversion medium completely covers the contaminant and penetrates well between the contaminant and the water-repellent surface without being repelled on the water-repellent surface by the action of the surfactant. It functions effectively as an energy conversion medium and can completely and reliably remove pollutants (by-products).

[0020]

As described above, according to the present invention, a substrate on which a contaminant (by-product) is adhered by a process such as ablation or film formation in which a resin is irradiated with a laser beam to perform a process.
By applying a liquid containing a surfactant as an energy conversion medium and irradiating it with a laser beam having a wavelength having selective absorption, the liquid containing a surfactant as an energy conversion medium is instantaneously evaporated. Even if the substrate has water repellency or the surface has been subjected to a water repellent treatment, a liquid containing a surfactant as an energy conversion medium can be used. It functions effectively without being repelled on the water-repellent surface, and can completely and reliably remove contaminants (by-products).

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining the effect of a liquid as an energy conversion medium on contaminants attached to a substrate subjected to a water-repellent treatment.

FIG. 2 is a configuration diagram schematically showing an example of an embodiment of a method for removing contaminants according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Q-switch YAG laser 2 Second harmonic generator SHG 3 Filter 4 Base material 5 Water repellent layer 6 Contaminant (by-product) 7 Liquid containing surfactant (energy conversion medium) 11 Water repellent treatment Substrate 12 Contaminant 13 Liquid without surfactant 14 Liquid with surfactant

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junji Tatsumi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Ken Ikegame 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside the corporation

Claims (3)

[Claims] An energy conversion medium is applied to a substrate to which contaminants are adhered, and is irradiated with a laser beam to instantaneously evaporate the energy conversion medium or convert light energy into kinetic energy. A method for removing contaminants, wherein a liquid containing a surfactant is used as the energy conversion medium. 2. The method for removing contaminants according to claim 1, wherein the liquid containing a surfactant absorbs laser light. 3. The method for removing contaminants according to claim 1, wherein the substrate is made of a material having water repellency or a material having a surface subjected to a water repellent treatment.