JP2006153998A - Method for forming pattern and pattern forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a pattern and a pattern forming apparatus for forming a fine pattern with thin width and a high aspect ratio by using long wavelength light which can be generated without using an expensive large device. <P>SOLUTION: A substrate 4 coated with a mixture 3 containing a light-absorbing heat conversion substance 1 which absorbs light at a specified wavelength to generate heat and a thermosensitive substance 2 which chemically reacts by the heat, is used and irradiated with laser light 6 emitting from a laser light source 5 and converged by a converging means 7 to form a pattern on the substrate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pattern forming method and a pattern forming apparatus for forming a pattern on a substrate.

  Usually, when a pattern is formed on a substrate such as a semiconductor substrate and a glass substrate, a lithography technique is used. The lithography technique is a method of forming a pattern on a substrate or the like by a coating process, an exposure process, a development process, or the like. In the coating process, a photoresist is applied to the substrate. In the exposure step, the photoresist is exposed by irradiating the photoresist with light based on the pattern to be formed on the substrate. In the developing step, a resist pattern is formed on the substrate by developing to remove either the exposed exposed portion or the non-exposed portion other than the exposed portion. A pattern is formed on the substrate through the above steps. Further, in the lithography technique, a pattern corresponding to the pattern of the resist is formed on the substrate by performing an etching process, a removing process, and the like. In the etching step, the substrate is etched using the resist pattern formed on the substrate as an etching mask. In the removing step, the etching mask is removed. Through the above process, a pattern such as a groove is formed on the substrate.

  In the exposure process, for example, a light exposure apparatus that exposes a photoresist using light having sensitivity is used. As a light exposure device, a light exposure is applied to a photomask for exposure on which a pattern is formed, and a projection exposure is performed on the photoresist, and laser light is directly irradiated onto the photoresist based on the pattern to be formed on the substrate. And an exposure apparatus.

  In recent years, high integration of substrates has been desired, and pattern miniaturization has been attempted. However, since the light exposure apparatus as described above has a diffraction limit in light, there is a limit in reducing a region where light is irradiated onto a substrate or the like. In other words, no matter how much the light is converged, the diameter of the region irradiated with the light is only about the wavelength of the light, so the diameter that is about the same as the wavelength of the used light becomes the pattern size limit. Therefore, in order to realize pattern miniaturization, the wavelength of light used is being shortened.

  Examples of the short wavelength light include ultraviolet light such as KrF excimer laser (wavelength: 248 nm), ArF excimer laser (wavelength: 193 nm), and F2 laser (wavelength: 157 nm). Furthermore, the use of EUV (Extreme Ultra Violet) light in the soft X-ray region having a wavelength of 5 to 15 nm, which is light having a shorter wavelength, is also being studied. However, any of the devices that generate light having a short wavelength as described above is very expensive and is a very large device.

  Therefore, it has been studied to use a light source for a pickup that is less expensive than a device that generates light having a short wavelength as described above and that can downsize the device. However, since the light source for pick-up is generally a light source that generates red light and infrared light, the pattern cannot be miniaturized because of the diffraction limit.

  In view of this, a method of converting light irradiated onto a substrate from a light source into heat and utilizing the heat has been studied. A typical prior art is described in US Pat. In the drawing method using the fine pattern drawing material of Patent Document 1, light is irradiated onto a substrate in which a light-absorbing heat conversion layer that absorbs light to generate heat and a heat-sensitive material layer that chemically reacts by heat is laminated. This is a method of drawing a pattern. Another conventional technique is described in Patent Document 2. The microfabrication method using the fine pattern drawing material disclosed in Patent Document 2 is a first inorganic substance layer that absorbs irradiated light and generates heat, and a second inorganic substance that reacts with the first inorganic substance by light irradiation. This is a method of irradiating a substrate having a composite layer composed of the above layers with light to perform microfabrication. Still another conventional technique is described in Patent Document 3. In the pattern forming method of Patent Document 3, a fine pattern is formed by irradiating light onto a substrate having a structure sandwiching a heat-sensitive material layer that absorbs heat and chemically reacts with a light absorption heat conversion layer that absorbs light and generates heat. It is a method of forming.

JP 2002-365806 A JP 2003-145941 A JP 2004-144925 A

  In general, the pattern forming method is desired not only to have a narrow width such as a resist pattern developed on a substrate and a pattern formed by etching, but also to have a high aspect ratio that is a ratio of height to depth or depth. .

  FIG. 7 is a schematic diagram showing a mechanism for forming a pattern by a conventional pattern forming method. FIG. 7A is a schematic diagram showing a mechanism for forming a pattern by irradiating the patterning material 101 for forming a pattern such as a photoresist with light 102 having a short wavelength. As shown in FIG. 7A, in the case of the short-wavelength light 102, the optical path irradiated with the short-wavelength light 102 becomes a reaction region 103 in which the patterning material 101 chemically reacts. Can be formed. However, it is difficult to form a pattern with a high aspect ratio if long wavelength light that is emitted from a light source for pickup is used instead of the short wavelength light 102.

  FIG. 7B is a schematic diagram showing a mechanism for forming a pattern using the methods described in Patent Documents 1 and 2. As shown in FIG. 7B, a long-wavelength light 105 is irradiated on a laminate of a patterning material 101 that chemically reacts by heat and a light absorption heat conversion layer 104 that absorbs light and generates heat. By doing so, the light absorption heat conversion layer 104 generates heat, and the patterning material 101 chemically reacts using the heat, whereby a narrow pattern can be formed. However, since only the patterning material 101 to which the heat generated in the light absorption heat conversion layer 104 is sufficiently transmitted undergoes a chemical reaction, the reaction region 103 is formed only around the patterning material 101 in contact with the light absorption heat conversion layer 104. Therefore, there is a problem that the reaction region 103 is not formed in the deep part of the patterning material 101 and a pattern with a high aspect ratio cannot be formed.

  FIG. 7C is a schematic diagram showing a mechanism for forming a pattern using the method described in Patent Document 3. As shown in FIG. As shown in FIG. 7C, in order to solve the problem that a pattern with a high aspect ratio cannot be formed, two light absorption heat conversion layers 104 are laminated so as to sandwich the patterning material 101. Then, the long wavelength light 105 is irradiated. Since the light absorption heat conversion layer 104 is in contact with both surfaces of the patterning material 101, the reaction region 103 can be formed deeper in the patterning material 101. However, since the reaction region 103 is formed only around the patterning material 101 in contact with the light absorption heat conversion layer 104, a pattern having a sufficiently high aspect ratio cannot be formed.

  Accordingly, an object of the present invention is to form a fine pattern with a narrow width and a high aspect ratio by using long-wavelength light that can be generated without using an expensive and large apparatus. Another object is to provide a pattern forming method and a pattern forming apparatus.

The present invention is a pattern forming method for forming a pattern on a substrate,
Irradiating a substrate coated with a mixture containing a light-absorbing heat-converting material that absorbs light having a specific wavelength to generate heat and a heat-sensitive material that chemically reacts with the heat with a laser beam having the specific wavelength Then, the pattern forming method is characterized by exposing the mixture.

  In the invention, it is preferable that the specific wavelength is longer than a wavelength of light that causes the heat-sensitive substance to chemically react by irradiating the heat-sensitive substance.

In the invention, it is preferable that the specific wavelength is an infrared wavelength.
Further, the present invention is characterized in that the specific wavelength is not less than 750 nm and not more than 950 nm.

  Further, the invention is characterized in that the light absorption heat conversion substance and the heat sensitive substance are organic compounds.

Further, the present invention is a pattern forming apparatus for forming a pattern on a substrate coated with a mixture containing a light-absorbing heat-converting substance that generates heat by absorbing infrared rays and a heat-sensitive substance that absorbs and reacts with heat,
A laser light source that emits laser light of an infrared wavelength;
The pattern forming apparatus includes a converging means for converging the laser beam.

  In addition, the present invention is characterized by including deflection control means for dividing and modulating the laser beam.

  In the invention, it is preferable that the deflection control means is a digital micromirror device.

  According to the present invention, the digital micromirror device is configured such that the laser beam is reflected and divided by a plurality of micromirrors, and the arrangement direction of the micromirror is inclined with respect to the traveling direction of the divided laser beam. It is characterized by.

Further, the invention is characterized in that the deflection control means is a liquid crystal element.
Further, the invention is characterized in that the laser light source can irradiate a plurality of laser beams simultaneously.

  According to the present invention, the laser light source is configured by arranging a plurality of light sources on the same plane.

  In the invention, it is preferable that the laser light source is a vertical cavity surface emitting laser element.

  According to the present invention, a specific wavelength is applied to a substrate coated with a mixture including a light-absorbing heat-converting material that absorbs light having a specific wavelength and generates heat, and a heat-sensitive material that chemically reacts with the heat. The mixture is exposed by irradiating the laser beam. By doing so, the mixture containing the light-absorbing heat converting substance generates heat, and the heat-sensitive substance causes a chemical reaction by the heat. Therefore, a pattern can be formed as long as the light-absorbing heat converting substance generates heat when irradiated with light.

  Further, the light intensity at the center of the region irradiated with light is the strongest, and the light intensity decreases as the distance from the center increases. That is, the intensity distribution of the irradiated light is a Gaussian distribution. If such a property that the intensity distribution of light has a Gaussian distribution is used, the region where the heat-sensitive substance chemically reacts can be made much smaller than the region irradiated with light. Therefore, the width of the formed pattern can be made very small.

  Further, since the light absorption heat conversion substance is dispersed in the heat sensitive substance, the light absorption heat conversion substance in the region irradiated with light can generate heat. Therefore, a heat sensitive substance deep in the thickness direction can also be chemically reacted, so that a pattern with a high aspect ratio can be formed.

  From the above, it is possible to form a fine pattern with a narrow width and a high aspect ratio by using long-wavelength light that can be generated without using an expensive and large apparatus.

  Further, according to the present invention, the specific wavelength is longer than the wavelength of light that causes the heat-sensitive material to chemically react by irradiating the heat-sensitive material. Therefore, when light is irradiated, the heat-sensitive substance does not chemically react, but when light is irradiated, the light-absorbing heat-converting substance generates heat, and the heat-sensitive substance chemically reacts only by the heat. Since it reacts, the influence of the diffraction limit of light is small, and a pattern with a smaller width can be formed.

  Further, according to the present invention, since the specific wavelength is an infrared wavelength, for example, 750 nm or more and 950 nm or less, a pattern can be formed without using an expensive and large apparatus.

  According to the present invention, since the light absorption heat conversion substance and the heat sensitive substance are organic compounds, the light absorption heat conversion substance and the heat sensitive substance are easily dispersed uniformly.

  Further, according to the present invention, the infrared wavelength laser light emitted from the laser light source is converged by the converging means, and the converged laser light is used. When a converged laser beam is applied to a substrate coated with a mixture of a light-absorbing heat-converting material that absorbs infrared rays and generates heat and a heat-sensitive material that absorbs heat and reacts, the light-absorbing heat-converting material generates heat. However, the heat sensitive substance chemically reacts with the heat. Therefore, a pattern can be formed even using light having a long wavelength such as an infrared wavelength.

  Further, the light intensity at the center of the region irradiated with light is the strongest, and the light intensity decreases as the distance from the center increases. That is, the intensity distribution of the irradiated light is a Gaussian distribution. If such a property that the intensity distribution of light has a Gaussian distribution is used, the region where the heat-sensitive substance chemically reacts can be made much smaller than the region irradiated with light. Therefore, the width of the formed pattern can be made very small.

  Further, since the light absorption heat conversion substance is dispersed in the heat sensitive substance, the light absorption heat conversion substance in the region irradiated with light can generate heat. Therefore, a heat sensitive substance deep in the thickness direction can also be chemically reacted, so that a pattern with a high aspect ratio can be formed.

  From the above, it is possible to form a fine pattern with a narrow width and a high aspect ratio by using long-wavelength light that can be generated without using an expensive and large apparatus.

  In addition, according to the present invention, the deflection control means for dividing and modulating the laser beam is included. By doing so, the laser beam is divided and modulated, so that a plurality of laser beams can be irradiated simultaneously. Therefore, the time for irradiating the laser beam can be shortened.

  According to the present invention, since the deflection control means is a digital micromirror device, the laser light is reflected and divided by the micromirror, so that a plurality of laser lights can be irradiated simultaneously. Therefore, the time for irradiating the laser beam can be shortened.

  According to the invention, the digital micromirror device reflects and divides the laser beam by the plurality of micromirrors, and the arrangement direction of the micromirror is inclined with respect to the traveling direction of the divided laser beam. Accordingly, since the divided laser beams do not overlap with each other, the laser beams can be efficiently irradiated, and the time for laser beam irradiation can be shortened.

  Further, according to the present invention, since the deflection control means is a liquid crystal element, the laser beam can be divided and a plurality of laser beams can be irradiated simultaneously. Therefore, the time for irradiating the laser beam can be shortened.

  According to the present invention, since the laser light source can irradiate a plurality of laser beams at the same time, it can irradiate a plurality of laser beams at the same time. Therefore, the time for irradiating the laser beam can be shortened.

  According to the present invention, since the laser light source is configured by arranging a plurality of light sources on the same plane, a plurality of laser beams can be irradiated simultaneously. Therefore, the time for irradiating the laser beam can be shortened.

  According to the present invention, since the laser light source is a vertical cavity surface emitting laser element, a plurality of light sources can be easily arranged on the same plane. Therefore, a plurality of laser beams can be irradiated at the same time, and the time for laser beam irradiation can be shortened.

  Hereinafter, the present invention will be described in detail by embodiments. The present invention is not limited to the present embodiment unless the gist thereof is changed.

  FIG. 1 is a schematic view for explaining the mechanism of the pattern forming method according to the present invention. In the pattern forming method according to the present invention, a mixture 3 including a light-absorbing heat-converting substance 1 that absorbs light having a specific wavelength to generate heat and a heat-sensitive substance 2 that chemically reacts with the heat is applied. A substrate 4 is used. Then, the laser light 6 emitted from the laser light source 5 is converged by the converging means 7 and then the substrate 4 is irradiated with the laser light 6.

  By doing so, the light absorption heat conversion substance 1 in the exposure part 8 exposed by the laser beam 6 generates heat, and the heat sensitive substance 2 is chemically reacted by the heat, and the exposure part 8 has physical properties such as solubility. It is different from the heat sensitive substance 2. A pattern on the substrate can be formed by dissolving and removing only the mixture 3 or dissolving and removing only the exposed portion 8 using a developer such as an alkaline solution.

  Further, the light intensity at the center of the region where the mixture 3 is irradiated with the laser light 6 is the strongest, and the light intensity decreases as the distance from the center increases. That is, the intensity distribution of the irradiated light is a Gaussian distribution. If such a property that the intensity distribution of light has a Gaussian distribution is used, the region where the heat-sensitive substance chemically reacts can be made much smaller than the region irradiated with light. Therefore, the width of the formed pattern can be made very small.

The light-absorbing heat converting material 1 can be any material that absorbs light and generates heat. For example, Ge—Sb—Te alloys such as Ge ₂ Sb ₂ Te ₅ , Sb metals, alloys such as Ag—In—Sb—Te alloys, Ag—In—Sb—Te—V alloys, lithium niobate and methyl Examples include nitroaniline.

  The light-absorbing heat conversion substance 1 is preferably a substance that generates heat by absorbing light having a wavelength longer than the wavelength of light that causes the heat-sensitive substance 2 to chemically react by irradiating the heat-sensitive substance 2. . If the light-absorbing heat converting substance 1 is such a substance, the light-sensitive heat-converting substance 1 is not irradiated with light, but the light-sensitive heat-converting substance 1 is irradiated with light. The heat sensitive material 2 chemically reacts only by the heat generated. Therefore, the influence of the diffraction limit of light is small, and a pattern with a smaller width can be formed.

Further, the light-absorbing heat converting substance 1 absorbs light having an infrared wavelength of 750 nm or more and 950 nm or less and generates heat, such as CD-R (Compact Disk Recordable) and DVD.
Organic pigment powder used in (Digital Versatile Disk) and the like is preferable. By doing so, the light-absorbing heat converting substance 1 can generate heat by the laser light emitted from the light source for pick-up, so that a pattern can be formed without using an expensive and large-sized device.

  Any material can be used as the heat-sensitive material 2 as long as the properties of the material are changed by heating and a pattern is formed by development processing. For example, a positive type photoresist, a negative type photoresist, and the like conventionally used in the lithography method can be mentioned.

  Moreover, it is preferable that the light absorption heat conversion substance 1 and the heat sensitive substance 2 are disperse | distributed uniformly. For example, both the light absorption heat conversion substance 1 and the heat sensitive substance 2 are made into organic compounds, or the light absorption heat conversion substance 1 and the heat sensitive substance 2 are applied to the substrate 4 immediately after stirring. By doing so, the light-absorbing heat converting substance 1 in the region irradiated with light can generate heat, and the heat-sensitive substance 2 located deep in the thickness direction can also be chemically reacted, so a high aspect ratio The pattern can be formed.

  Any substrate can be used as long as it is normally used as a substrate in a conventional lithography method. For example, inorganic substrates such as silicon, silicon oxide, tantalum, aluminum, gallium-arsenic, glass plate, plastic substrates such as polypropylene, acrylic resin, polycarbonate, styrene resin, vinyl chloride resin, glass on which aluminum and tantalum are deposited Examples thereof include a plate and a glass plate coated with a photocurable resin layer.

Moreover, you may apply | coat the mixture 3 containing the light absorption heat conversion substance 1 and the heat sensitive substance 2 to the board | substrate 4 with which the board | substrate protective layer is formed. By doing so, the substrate 4 can be protected even when the substrate 4 is damaged by the heat generated from the light-absorbing heat converting substance 1. As a material for the substrate protective layer, for example, an inorganic compound such as ZnS.SiO ₂ and an organic compound such as polyimide can be used.

  From the above, the pattern forming method of the present invention is a fine pattern with a narrow width and a high aspect ratio using long-wavelength light that can be generated without using an expensive and large-sized apparatus. Can be formed.

A pattern forming apparatus according to the present invention is an apparatus using the pattern forming method described above. The pattern forming apparatus according to the present invention may be an apparatus using a pattern forming method for irradiating one place of the substrate 4 shown in FIG. 1 with a laser beam, or simultaneously irradiating a plurality of places on the substrate 4 with a laser beam. It may be a pattern forming apparatus. Examples of the pattern forming apparatus that simultaneously irradiates a plurality of locations on the substrate 4 with laser light include a pattern forming apparatus that divides the laser light by a deflection control unit and a pattern forming apparatus that uses a light source that can generate a plurality of laser lights. It is done.
First, a pattern forming apparatus that divides laser light by deflection control means will be described.

  FIG. 2 is a schematic diagram showing the configuration of the pattern forming apparatus 11 according to the present invention. The pattern forming apparatus 11 is a pattern forming apparatus including a laser light source 21, a digital micromirror device 22, and a converging unit 23.

  When the laser light source 21 irradiates the light absorption heat conversion material applied on the substrate 24, the laser light source 21 emits laser light having a specific wavelength that generates heat from the light absorption heat conversion material. The digital micromirror device 22 is configured by arranging a plurality of micromirrors 25 in an array on the surface thereof. The digital micromirror device 22 reflects the irradiated laser light by each micromirror 25 and divides the laser light. Furthermore, the digital micromirror device 22 can control the traveling direction of the divided laser light by changing the angle at which the micromirror 25 is installed. The digital micromirror device 22 is a deflection control means. The converging means 23 is realized by a lens or the like, and converges the laser light applied to the substrate.

  The pattern forming apparatus 11 moves the stage 26 on which the substrate 24 is placed in a certain direction and turns on / off the irradiation of the laser beam, thereby irradiating the substrate 24 with the laser beam when it is necessary to irradiate the pattern. A pattern is formed by a raster scanning method for forming the pattern. The laser light irradiation is turned on / off by changing the angle of the micromirror 25 that reflects the laser light irradiated to the digital micromirror device 22.

  From the above, when a pattern is formed using the pattern forming apparatus 11, a plurality of locations on the substrate can be irradiated simultaneously with a plurality of laser beams, so that the irradiation time of the laser beams can be shortened. Furthermore, since the laser light emitted from the laser light source 21 is reflected by the digital micromirror device 22, it is not necessary for the laser light emitted from the laser light source 21 to be directed toward the substrate. it can.

  FIG. 3 is a schematic diagram for explaining the relationship between the traveling direction 31 of the laser light divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25. FIG. 3A is a schematic view when the traveling direction 31 of the laser beam divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25 are not inclined. FIG. 3B is a schematic diagram when the traveling direction 31 of the laser light divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25 are inclined.

  As shown in FIG. 3A, when the traveling direction 31 of the laser beam divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25 are not inclined, the digital micromirror device 22 is irradiated. When the laser light is reflected in a certain direction of the substrate by the micromirror 25, the traveling direction 31 of the laser light divided by the digital micromirror device 22 coincides with the arrangement direction 32 of the micromirror 25, and at the same time on the substrate. Not much laser light can be irradiated. For example, when the digital micromirror device 22 arranged in a three-by-three lattice pattern is used, even if nine micromirrors 25 are arranged, only three portions of the substrate can be irradiated simultaneously with laser light. Can not. On the other hand, as shown in FIG. 3B, when the traveling direction 31 of the laser beam divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25 are inclined, the digital micromirror device When the laser light applied to 22 is reflected by the micromirror 25 in a certain direction of the substrate, the traveling direction 31 of the laser light divided by the digital micromirror device 22 does not coincide with the arrangement direction 32 of the micromirror 25. At the same time, the amount of laser light that can be irradiated onto the substrate can be increased. For example, in the case of using the digital micromirror device 22 arranged in the form of a lattice of 3 by 3 vertically, 9 micromirrors 25 are arranged in the digital micromirror device 22, and the 9 micromirrors 25 Since the reflected laser beams can be irradiated to different portions of the substrate, nine portions of the substrate can be irradiated simultaneously. Therefore, by installing the digital micromirror device 22 so that the traveling direction 31 of the laser beam divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25 are inclined, more portions of the substrate 24 are arranged. Since the laser beam can be irradiated simultaneously, the irradiation time of the laser beam can be further shortened.

  FIG. 4 is a schematic view showing the configuration of the pattern forming apparatus 12 according to the present invention. The pattern forming apparatus 12 is the same as the pattern forming apparatus 11 except that the deflection control means is a liquid crystal element 27 instead of the digital micromirror device 22. The liquid crystal element 27 is configured by arranging a plurality of liquid crystal shutters 28 that transmit and block light by changing light transmittance in an array. The liquid crystal element 27 transmits the irradiated laser light to the respective liquid crystal shutters 28 and divides the laser light.

  The pattern forming device 12 changes the light transmittance of the liquid crystal shutter 28 to transmit and block the laser light applied to the liquid crystal element 27, thereby turning on and off the laser light irradiation.

  From the above, when a pattern is formed using the pattern forming apparatus 12, a plurality of locations on the substrate can be irradiated simultaneously with a plurality of laser beams, so that the irradiation time of the laser beams can be shortened.

  Next, a pattern forming apparatus using a light source capable of generating a plurality of laser beams will be described.

  FIG. 5 is a schematic diagram showing the configuration of the pattern forming apparatus 13 according to the present invention. The pattern forming apparatus 13 is a pattern forming apparatus including a laser light source 29 and a converging unit 23.

  The laser light source 29 is configured by arranging a plurality of light sources 30 on the same plane. Therefore, a plurality of laser beams can be irradiated simultaneously. For example, a vertical cavity surface emitting laser element (VCSEL) is preferable because a plurality of light sources 30 can be easily arranged on the same plane.

  The pattern forming apparatus 13 turns on / off the laser light by turning on / off the plurality of light sources 30 respectively.

  Therefore, when a pattern is formed using the pattern forming apparatus 13, a plurality of locations on the substrate can be irradiated simultaneously with a plurality of laser beams, so that the irradiation time of the laser beams can be shortened.

Examples using the pattern forming method according to the present invention will be described below.
In Examples, an organic dye powder used in CD-R was used as the light-absorbing heat conversion substance 1, and a photoresist (AZ5214E manufactured by Clariant Japan Co., Ltd.) was used as the heat-sensitive substance 2. This photoresist has only about 4% of reactivity when irradiated with light having a wavelength of 450 nm or longer, and when irradiated with light having a maximum reactivity of 380 nm. It also has the characteristic of change in dissolution rate due to.

  The organic dye powder and the photoresist were stirred, and the stirred mixture was applied to the optical disk substrate so as to have a film thickness of 0.8 μm or more and 1.0 μm or less. Using a CD optical disk drive, the substrate on which the mixture was applied was irradiated with laser light so that the linear velocity, which is the velocity at which the light source traces the substrate, was 3 m / sec. The laser light has an output of about 15 mW on the substrate with a wavelength of 850 μm.

  Then, the mixture which has not been irradiated with the laser beam was removed using a resist stripping solution (manufactured by Rasa Industrial Co., Ltd., RS-30PE).

  The SEM (scanning electron microscope) photograph of the substrate was observed, and the result is shown in FIG. FIG. 6 is a SEM (scanning electron microscope) photograph of the resist pattern formed on the substrate in the example. As shown in the SEM photograph of FIG. 6, a pattern having a height in the depth direction of 1.0 μm and a width of 0.552 μm was formed on the substrate.

It is the schematic explaining the mechanism of the pattern formation method which is this invention. It is the schematic which shows the structure of the pattern formation apparatus 11 which is this invention. FIG. 6 is a schematic diagram for explaining the relationship between the traveling direction 31 of the laser light divided by the digital micromirror device 22 and the arrangement direction 32 of the micromirror 25. It is the schematic which shows the structure of the pattern formation apparatus 12 which is this invention. It is the schematic which shows the structure of the pattern formation apparatus 13 which is this invention. It is a SEM (scanning electron microscope) photograph of the resist pattern formed on the board | substrate in an Example. It is a schematic diagram which shows the mechanism which forms a pattern with the conventional pattern formation method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light absorption heat conversion substance 2 Heat sensitive substance 3 Mixture 4 Substrate 5 Laser light source 6 Laser light 7 Converging means 8 Exposure part 11, 12, 13 Pattern formation apparatus 21, 29 Laser light source 22 Digital micromirror device 23 Converging means 24 Substrate 25 Micro mirror 26 Stage 27 Liquid crystal element 28 Liquid crystal shutter 30 Light source 31 Traveling direction 32 Arrangement direction 101 Patterning material 102 Short wavelength light 103 Reaction region 104 Light absorption heat conversion layer 105 Long wavelength light

Claims (13)

A pattern forming method for forming a pattern on a substrate,
Irradiating a substrate coated with a mixture containing a light-absorbing heat-converting material that absorbs light having a specific wavelength to generate heat and a heat-sensitive material that chemically reacts with the heat with a laser beam having the specific wavelength And exposing the mixture to a pattern.   2. The pattern forming method according to claim 1, wherein the specific wavelength is longer than a wavelength of light that causes the heat-sensitive substance to chemically react by irradiating the heat-sensitive substance.   The pattern forming method according to claim 1, wherein the specific wavelength is an infrared wavelength.   The pattern formation method according to claim 1, wherein the specific wavelength is not less than 750 nm and not more than 950 nm.   The pattern forming method according to claim 1, wherein the light absorption heat conversion substance and the heat sensitive substance are organic compounds. A pattern forming apparatus for forming a pattern on a substrate coated with a mixture comprising a light-absorbing heat converting material that absorbs infrared rays and generates heat and a heat-sensitive material that absorbs and reacts with heat,
A laser light source that emits laser light of an infrared wavelength;
A pattern forming apparatus comprising: a converging unit for converging the laser beam.   7. The pattern forming apparatus according to claim 6, further comprising a deflection control unit that divides and modulates the laser beam.   8. The pattern forming apparatus according to claim 7, wherein the deflection control means is a digital micromirror device.   The digital micromirror device is characterized in that the laser beam is reflected and divided by a plurality of micromirrors, and the arrangement direction of the micromirror is inclined with respect to the traveling direction of the divided laser beam. Item 9. The pattern forming apparatus according to Item 8.   8. The pattern forming apparatus according to claim 7, wherein the deflection control means is a liquid crystal element.   The pattern forming apparatus according to claim 6, wherein the laser light source is capable of simultaneously irradiating a plurality of laser beams.   12. The pattern forming apparatus according to claim 6, wherein the laser light source is configured by arranging a plurality of light sources on the same plane.   The pattern forming apparatus according to claim 6, wherein the laser light source is a vertical cavity surface emitting laser element.