JP2006272040A - Method of forming functional film pattern and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of forming a functional film pattern permitting formation of a good functional film pattern by utilizing input electromagnetic energy efficiently and intended to allow miniaturization of the installation of a needed light source and electronic equipment having a functional film pattern formed by the method. <P>SOLUTION: The method repeats, respectively three times, a process of adhering liquid droplets 30 containing a functional material as a functional liquid material onto a substrate 21 and forming film patterns 40 and 41 and a process of irradiating the film patterns with a laser beam 50 as an electromagnetic wave to bake the film patterns with the heat generated through light-heat conversion so as to form one circuit pattern in the form of three divided layers 19a to 19c. The method enables utilization of the light-heat conversion phenomenon occurred on the front surface every time one of the layers 19a to 19c is formed, ensuring formation of each layer with consistently high absorption efficiency. The method provides a structure in each layer of which conductivity is presented uniformly at a practically equal level, and the inside of the circuit pattern 19 composed of the laminated layers constitutes a consistent structure in which conductivity is presented uniformly at a practically equal level. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a functional film pattern forming method and an electronic apparatus for forming a functional film pattern of various devices.

  Conventionally, a photolithography method is generally known as a method for forming functional film patterns of various devices. It can be said that this method is wasteful, such as throwing away most of the material. As a method for forming a functional film pattern in place of the photolithography method, direct drawing by a screen printing method, a micro-dispensing method, a droplet discharge method (ink jet method) or the like is known (for example, see Patent Document 1).

  In order to perform such direct drawing, unlike the sputtering method, it is necessary to use a functional material that has been converted into fine particles and dispersed in a solution, or in an ink or paste by dissolving in a suitable solvent. . For this reason, since the performance as a functional film pattern cannot be exhibited simply by patterning the wiring by direct drawing, a baking process including drying and sintering using an oven or the like as a post-process to obtain the desired performance Is required.

Since the current firing process requires a time of about 30 minutes to 1 hour or more, this firing process is a factor of reducing the throughput. In order to avoid this, as a baking process with a fast processing time instead of an oven or the like, an electromagnetic wave irradiation method in which the film pattern patterned by direct drawing is irradiated with electromagnetic waves and the above baking process is performed by the action of heat generated by photothermal conversion. Can be considered.
Japanese Patent Application Laid-Open No. 2002-261048

By the way, when the functional material is baked (including drying and sintering) by irradiating electromagnetic waves onto the film pattern patterned by direct drawing as described above, it is necessary to form a functional film pattern per unit area. The amount of irradiation energy is about 0.1 to 100 J / mm ² , although it varies depending on the substrate used, ink type, ink amount, electromagnetic spectrum, and the like. The following formula,
(Amount of electromagnetic wave irradiation energy per unit area) = (electromagnetic wave output x irradiation time / electromagnetic wave spot area)
In the range where the above relationship holds, the electromagnetic wave output, the irradiation time, and the spot area are adjusted so as to ensure the irradiation energy amount necessary for firing, and the film pattern is irradiated with the electromagnetic wave.

  In this case, the irradiation time can be shortened by increasing the irradiation intensity (= electromagnetic wave output / spot area), increasing the electromagnetic wave output and / or reducing the spot area under a constant amount of irradiation energy.

  However, when the above baking process is performed by irradiating the film pattern with electromagnetic waves, very high density energy must be input in order to sufficiently advance drying and sintering. This is because, as the firing process proceeds, the absorption spectrum of the film pattern changes and the absorption efficiency decreases, so that the photothermal conversion efficiency at the laser irradiation wavelength is extremely reduced.

In addition, since it is necessary to input energy of light density, for example, when the present technology is applied to a large area, there is a problem that a necessary light source facility becomes large.
The present invention has been made paying attention to such conventional problems, and the object thereof is to efficiently use the input energy of electromagnetic waves, and to form a good-quality functional film pattern. To provide a functional film pattern forming method and an electronic device in which a light source facility is miniaturized.

  The functional film pattern deposition method in the present invention includes a first step of forming a film pattern by attaching a functional liquid material on a substrate, and heat generated by photothermal conversion by irradiating the film pattern with electromagnetic waves. The gist is to form a single functional film pattern in a plurality of layers by repeating the second step of causing the film pattern to exhibit functionality and a plurality of times.

  When a film pattern containing functional materials is irradiated with electromagnetic waves and the heat generated by photothermal conversion causes the film pattern to exhibit functionality, photothermal conversion occurs mainly on the surface side of the film pattern, and the surface side functions first. It becomes a structure that expresses sex. Therefore, in the case of forming a thick film pattern at once and irradiating it with an electromagnetic wave to form a thick functional film pattern, it is difficult to make the entire structure to have the same level of functionality. .

  According to the present invention, the first step of forming a film pattern by depositing a functional liquid material on a substrate and the second step of irradiating the film pattern with electromagnetic waves to develop functionality are repeated a plurality of times. Since one functional film pattern is divided into a plurality of layers, a phenomenon in which photothermal conversion occurs mainly on the surface side can be used each time each layer of one functional film pattern is formed. That is, when the functional liquid material is adhered to the substrate and a process for expressing the functionality (for example, a baking process including drying and sintering) is performed at a time, the phenomenon can be used only once. On the other hand, according to the present invention, the phenomenon can be used a plurality of times, and each layer of one functional film pattern can always be formed with high absorption efficiency. As a result, a functional film pattern is divided into a plurality of layers, and the inside of each layer has a structure in which the functionality is expressed uniformly and at the same level, and the entire inside of one functional film pattern formed by stacking these layers. However, compared to the case where the functional liquid material is adhered to the substrate and the process for expressing the functionality is performed at once, the structure is such that the functionality is expressed uniformly and to the same extent. Here, “absorption efficiency” refers to photothermal conversion efficiency when heat is generated by photothermal conversion by electromagnetic wave absorption.

Moreover, since the heat generated in each layer after the second layer is also transmitted to the lower layer, it is possible to further promote the functional expression in the lower layer.
Therefore, it is possible to form a high-quality functional film pattern by efficiently using the input energy. In particular, it is effective for forming a thick functional film pattern. In addition, since it is not necessary to input very high density energy, it is possible to reduce the size of the light source equipment.

  In this functional film pattern forming method, the functional liquid material is a finely divided functional material coated with a dispersant, dissolved in a solvent, or dispersed in a dispersant to make an ink or paste. In the second step performed a plurality of times, the functional film is formed in order from the first layer by sequentially firing the film pattern with the heat generated by the photothermal conversion to form each layer of the functional film pattern. The gist is that the first layer of the pattern is fired to the extent that the fine particles melt and grow as a result of the firing and the surface becomes a reflective surface.

  When a film pattern containing fine particles is irradiated with electromagnetic waves and baked with heat generated by photothermal conversion, fine particles on the surface side of the film pattern are first sintered. Therefore, when a thick film pattern is formed at a time and an electromagnetic wave is irradiated to form a functional film pattern, the inner fine particles are not baked as much as the surface side. For this reason, it is difficult to form a high-quality functional film pattern in which fine particles are enlarged throughout. This becomes remarkable when a thick functional film pattern is formed.

  According to this, the first layer of the functional film pattern is baked to the extent that the fine particles melt and grow to form a reflective surface by firing, so when forming the second and subsequent layers of the functional film pattern In addition, the energy of the electromagnetic wave reflected by the surface of the first layer serving as the reflection surface can be used. For example, when forming the second layer of the functional film pattern, the electromagnetic wave that has not been absorbed by the second layer film pattern is reflected by the surface of the first layer and again applied to the second layer film pattern. It is absorbed and generates heat by photothermal conversion. The heat can promote firing of the second layer. When forming the third and subsequent layers of the functional film pattern, as in the case of the second layer, it is reflected by the surface of the first layer and again applied to the film pattern of the third and subsequent layers and absorbed by photothermal conversion. Heat is generated. The heat can promote firing in the third and subsequent layers.

  In this way, the energy of the electromagnetic wave reflected on the surface of the first layer (irregular reflection on the surface of the grown fine particles) can be utilized by repeating the adhesion of the functional liquid material onto the substrate and the irradiation of the electromagnetic wave a plurality of times. , Photothermal conversion efficiency is improved. Therefore, the photothermal conversion efficiency can be greatly improved compared to the case where the functional liquid material is adhered and fired on the substrate at one time, and the total input necessary for firing one functional film pattern. The amount of energy can be reduced.

  Moreover, since the heat generated in each layer after the second layer is also transmitted to the lower layer that has already been fired, the lower layer can be further fired. For this reason, metal fine particles become large even in the inner part of the film pattern (the part far from the surface side), and a high-quality functional film pattern in which the metal fine particles become larger in the entire interior can be made. Moreover, even a thick functional film pattern can be produced efficiently.

  In this functional film pattern deposition method, the first layer of the functional film pattern is baked by increasing the input energy amount of the electromagnetic wave as compared with the second and subsequent layers of the functional film pattern.

  According to this, after the second layer, the firing may be performed with a small amount of input energy so that the reflection on the surface of the first layer can be used. As a result, the amount of input energy in the second and subsequent layers can be reduced, so that a functional film pattern having the same thickness can be formed compared to the case where the functional liquid material is deposited on the substrate and fired at once. Further, the total input energy amount can be further reduced.

The gist of the functional film pattern forming method is that the functional material is finely divided into metal fine particles.
According to this, a high-quality wiring pattern can be formed as the functional film pattern by efficiently using the input energy. In particular, this is effective for forming a thick wiring pattern.

The gist of the electronic device according to the present invention is that it includes the functional film pattern formed by the functional film pattern forming method.
According to this, a high-performance functional film pattern can be formed by efficiently using the input energy by the functional film pattern forming method, so that a high-performance electronic device can be realized at low cost. it can.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. In the following embodiments, as an example of the functional film pattern, a wiring pattern (metal wiring pattern) such as a scanning line or a data line formed on an element substrate of a display device such as a plasma display or a metal wiring of a circuit board A case where a pattern is formed will be described.

  Before describing a functional film pattern film forming method according to an embodiment, a functional film pattern film forming apparatus 20 used for carrying out this functional film pattern film forming method will be briefly described with reference to FIG.

  As shown in FIG. 1A, this functional film pattern film forming apparatus 20 has a carriage on which a substrate 21 on which a wiring pattern 19 (see FIG. 1C) as a functional film pattern is formed is placed. 22, a droplet discharge head 23 as an apparatus for attaching a functional liquid material onto a substrate, a laser light irradiation head 24 as an electromagnetic wave light source, and a control unit 25.

  The carriage 22 is driven by an X-direction drive motor and a Y-direction drive motor (not shown) and can move in the XY directions with respect to the droplet discharge head 23. In FIG. 1A, the substrate 21 is transported in the substrate traveling direction indicated by an arrow.

  The droplet discharge head 23 discharges a droplet 30 containing a functional material as a functional liquid material onto the substrate 21. As shown by the enlarged portions 60 and 61 in FIG. 1A, the droplet 30 is an ink formed by dispersing fine particles of metal as a functional material (metal fine particles 31) in a solvent 32. is there. Further, since the metal fine particles 31 adhere to the droplet 30 as they are and melt, the metal fine particles 31 are coated with a protective film made of a dispersant 33 and dispersed. In this example, silver fine particles are used as the metal fine particles 31. Further, the droplet discharge head 23 discharges the droplet 30 so that the droplets 30 that have landed on the substrate 21 aggregate and a predetermined film pattern 40 is formed on the substrate 21. Liquid repellent treatment is applied to necessary portions on the substrate 21 so that the film pattern 40 is formed on the substrate 21.

  The control unit 25 outputs control signals to each of the droplet discharge head 23, the carriage 22, and the laser beam irradiation head 24, and performs overall control of the entire system including them. The controller 25 includes a CPU (not shown), a timer clock, a memory storing the shape and position of the film pattern, and the like.

  Here, the firing process in which the firing of the film pattern 40 proceeds by the heat generated by the photothermal conversion by the absorption of the laser light and the wiring pattern 19 is formed will be described. This firing process can be divided into the following three steps (stages).

Early firing: In this early firing, the solvent 32 and the dispersant 33 are decomposed, evaporated and scattered.
Curves 42 and 43 in FIG. 2 indicate the absorption spectrum of the functional material at the initial stage of firing, that is, the absorption spectrum of the film pattern 40 including the metal fine particles 31, the solvent 32, and the dispersant 33. This absorption spectrum is simply represented by the absorption spectrum caused by the solvent shown by the curves 44 and 45 in FIG. 3A, the absorption spectrum caused by the dispersant shown by the curves 46 and 47 in FIG. The absorption spectrum due to the fine particles (solute) indicated by the curve 48 in (C) is superimposed. Curves 80 and 81 in FIG. 4A show the absorption spectrum at the initial stage of firing.

  In this way, in the initial stage of sintering, absorption caused by the metal fine particles 31, the solvent 32, and the dispersing agent 33 has occurred, so that it is the easiest region to proceed with the sintering. In addition, when the metal is made into fine particles, a characteristic of plasmon absorption that has not been seen in the bulk appears, and it resonates with light of a certain wavelength and exhibits very large absorption. This is effective when the fine particles (metal fine particles 31) are of a certain size, and plasmon absorption decreases as sintering proceeds and the fine particles become larger.

Middle firing stage: In the middle firing stage, the residual amount of the solvent 32 and the dispersant 33 decreases, and the metal fine particles 31 melt (solute precipitates) to start grain growth. The absorption spectrum caused by the solvent disappears, and the intensity of the absorption spectrum caused by the dispersant decreases. The absorption spectrum due to the fine particles (solute) becomes broad as the particle diameter grows. In this process, the solvent evaporates and the dispersant is decomposed and removed, so that absorption due to the solvent and the dispersant is steadily reduced. Moreover, since the diameter of the metal fine particles 31 becomes larger and larger, plasmon absorption also decreases. Curves 82 and 83 in FIG. 4B show the absorption spectrum in the middle of firing.

  Late firing stage: In this late firing stage, as shown schematically by the enlarged portion 60 in FIG. 1A and the enlarged portion 62 in FIG. 1B, the grain growth of the metal fine particles 31 proceeds and functions as the wiring pattern 19. Sex is expressed. The absorption spectrum due to the fine particles also begins to disappear, and the original absorption spectrum of the film becomes dominant. A curve 84 in FIG. 4C shows an absorption spectrum in the later stage of firing.

  The functional film pattern deposition apparatus 20 emits laser light having an optimum wavelength with good absorption efficiency according to the absorption spectrum of the film pattern 40 that changes in each process from the initial stage of baking to the final stage of baking when the wiring pattern 19 is formed. A laser beam irradiation head 24 for irradiation is provided.

  The laser beam irradiation head 24 irradiates the film pattern 40 with a laser beam 50 having an optimum wavelength with good absorption efficiency. The laser light irradiation head 24 includes a laser main body 51 that emits laser light 50 and a lens 52 that condenses the laser light 50 emitted from the laser main body 51 on the film pattern 40 in a desired spot shape.

  The laser beam 50 is green light. The laser body 51 uses, for example, an Nd: YAG laser (wavelength λ1 = 532 nm). The laser main body 51 is driven and controlled by the control unit 25 so as to emit the laser light 50 continuously. The laser beam irradiation head 24 having such a configuration is disposed in the vicinity of the droplet discharge head 23.

Next, a functional film pattern film forming method according to the embodiment performed using the functional film pattern film forming apparatus 20 having the above configuration will be described.
This functional film pattern forming method is characterized in that the following first step and second step are repeated a plurality of times to form one wiring pattern (functional film pattern) 19 in a plurality of layers. In the point. In this example, as an example, the first step and the second step are repeated three times to form the wiring pattern 19 in three layers 19a to 19c as shown in FIG.

(First step)
A droplet 30 containing a functional material as a functional liquid material is deposited on the substrate 21 to form a film pattern 40. That is, in this process, the functional liquid material is adhered on the substrate 21 to form the film pattern 40. A film pattern 40 shown in FIG. 1A is a film pattern for forming the first layer 19a of the wiring pattern 19 divided into three layers 19a to 19c. A film pattern 41 shown in FIG. 1B is a film pattern for forming the second layer 19b.

(Second step)
The film pattern 40 or 41 is irradiated with a laser beam 50 as an electromagnetic wave, and the film pattern 40 or 41 is caused to exhibit functionality by heat generated by photothermal conversion.

  The droplets 30 used in this functional film pattern forming method are coated with a dispersing agent 33 on metal fine particles 31 obtained by atomizing a metal as a functional material, as shown by enlarged portions 60 and 61 in FIG. Then, the ink is dissolved in the solvent 32 to form an ink.

In this functional film pattern forming method, in the second step performed three times, the first layer film pattern 40, the second layer film pattern 41, and the third layer are generated by heat generated by photothermal conversion. The film pattern (not shown) is fired to form the layers 19a to 19c of the wiring pattern 19 in order from the first layer 19a to the third layer 19c. At this time, as shown in the enlarged portion 60 of FIG. 1A and the enlarged portion 62 of FIG. 1B, the first layer 19a is melted and grown by the above baking process, and the surface ( Baking is performed to the extent that the uneven surface becomes the reflecting surface 55.

  Specifically, in this functional film pattern film forming method, the first step and the second step are repeated three times in the following procedures (1) to (6) to obtain one wiring pattern 19. Are divided into three layers 19a to 19c.

(1) First, as shown in FIG. 1A, a droplet (functional liquid material) 30 is attached on a substrate 21 to form a film pattern 40.
(2) Next, the film pattern 40 is fired (including drying and sintering) by heat generated by photothermal conversion by irradiating the film pattern 40 with the laser beam 50, and the functionality (conductivity) as a wiring pattern is obtained. The expressed first layer 19a is formed.

(3) Next, as shown in FIG. 1 (B), the droplet 30 is deposited on the first layer 19a to form a film pattern 41.
(4) Next, the film pattern 41 is baked by heat generated by photothermal conversion by irradiating the film pattern 41 with the laser beam 50 to form the second layer 19b exhibiting the functionality as a wiring pattern (FIG. 1 (B) and (C)).

(5) Next, the droplet 30 is attached on the second layer 19b to form a film pattern (not shown) for the third layer.
(6) Next, a laser beam 50 is irradiated onto the film pattern for the third layer, the film pattern is baked by heat generated by photothermal conversion, and the third layer 19c that exhibits the functionality as the wiring pattern is obtained. It is formed (see FIG. 1C).

By such a procedure, one wiring pattern 19 is completed from the three layers 19a to 19c as shown in FIG.
Further, in the functional film pattern forming method according to the present embodiment, the first layer 19a of the wiring pattern 19 has an input energy amount of the laser light 50 higher than that of the second and subsequent layers (second layer 19b and third layer 19c). Increase the amount and bake.

According to the embodiment configured as described above, the following operational effects can be obtained.
○ The first step and the second step are repeated three times to form one wiring pattern 19 in three layers 19a to 19c, so that each layer 19a to 19c of one wiring pattern 19 is formed. Each time, the phenomenon that photothermal conversion occurs mainly on the surface side can be used. That is, when the functional liquid material is adhered to the substrate and the process for expressing the functionality (for example, a baking process including drying and sintering) is performed at a time, the phenomenon can be used only once. On the other hand, according to the present embodiment, the phenomenon can be used three times, and the layers 19a to 19c can be always formed with high absorption efficiency. As a result, a structure in which the conductivity (functionality) is expressed uniformly and at the same level inside each layer obtained by dividing one wiring pattern 19 into three layers 19a to 19c. For this reason, the entire inside of one wiring pattern 19 formed by stacking these layers is more uniform in conductivity than the case where the process of causing the functional liquid material to adhere to the substrate and exhibit the functionality is performed at once. The structure is expressed to the same extent.

In addition, since heat generated in each of the second and subsequent layers (second layer 19b and third layer 19c) is transmitted to the lower layer, it is possible to further develop the conductivity in the lower layer.
Therefore, a high-quality wiring pattern can be formed by efficiently using the input energy. In particular, this is effective for forming a thick wiring pattern.

○ Since it is not necessary to input very high density energy, the size of the light source equipment can be reduced.
The first layer 19a of the wiring pattern 19 is baked to the extent that the metal fine particles 31 melt and grow as a result of firing, and the surface (see FIG. 1B) becomes the reflecting surface 55. When forming the second and subsequent eyes, the energy of the laser light (see the enlarged portion 62 in the figure) reflected by the reflecting surface 55 of the first layer 19a serving as the reflecting surface can be used.

  For example, when the second layer 19b of the wiring pattern 19 is formed, the laser light that has not been absorbed by the second layer film pattern 41 is reflected by the reflecting surface 55 of the first layer 19a, and again the second layer film. It is applied to the pattern 41 and absorbed, and heat is generated by photothermal conversion. The heat of the second layer 19b can be promoted by the heat. When the third layer 19c of the wiring pattern 19 is formed, as in the case of the second layer 19b, it is reflected by the reflecting surface 55 of the first layer 19a and again applied to the film pattern of the third layer and absorbed. Heat is generated by the conversion. The heat can promote firing of the third layer.

  As described above, the laser beam reflected by the reflecting surface 55 of the first layer 19a (irregularly reflected on the surface of the grown metal fine particles) is obtained by repeating the attachment of the droplet 30 and the irradiation of the laser beam 50 a plurality of times (three times). Since 50 energy can be utilized, photothermal conversion efficiency improves. Therefore, compared with the case where the functional liquid material is adhered and fired on the substrate at once, the photothermal conversion efficiency can be greatly improved, and the total input energy required for firing one wiring pattern 19 The amount can be reduced.

  Since the heat generated in each layer after the second layer is also transferred to the lower layer that has already been fired, the lower layer can be further fired. For this reason, the metal fine particles 31 become large even in the inner part of the film patterns 40 and 41 (the part far from the surface side), and a high-quality wiring pattern 19 in which the metal fine particles 31 become large in the entire interior can be made.

O Even a thick wiring pattern 19 can be produced efficiently.
The second layer 19b and subsequent layers (the second layer 19b and the third layer 19c) may be fired with an input energy amount that is small enough to use the reflection on the reflecting surface 55 of the first layer 19a. Thereby, since the amount of input energy after the second layer can be reduced, in order to form the wiring pattern 19 of the same thickness, compared to the case where the functional liquid material is adhered to the substrate and fired at a time, The total input energy can be further reduced.

(Electronics)
Next, a mobile personal computer will be described with reference to FIG. 5 as an example of an electronic apparatus provided with the wiring pattern 19 formed by the functional film pattern forming method described in the above embodiment.

  A personal computer 70 shown in FIG. 5 includes a main body 72 having a keyboard 71 and a display unit 73 using an organic EL panel. On the element substrate (not shown) of the display unit 73, a plurality of scanning lines, a plurality of data lines, and a plurality of light-emitting elements are arranged in a matrix corresponding to the intersections of the scanning lines and the data lines. Pixels are formed. Wiring patterns such as scanning lines and data lines are formed by the functional film pattern forming method described in the above embodiment.

According to the personal computer 70, the functional film pattern forming method can efficiently use the input energy to form a high-quality wiring pattern 19 (see FIG. 1C). Thus, a high-performance personal computer 70 can be realized.

In addition, this invention can also be changed and embodied as follows.
In the above embodiment, in the first step, the film pattern 40 is formed by attaching the droplet 30 containing the functional material as the functional liquid material on the substrate 21. That is, the functional liquid material is deposited on the substrate 21 in the first step by an inkjet method using the functional film pattern film forming apparatus 20 including the droplet discharge head 23 and the laser light irradiation head 24. However, the present invention is not limited to this. The present invention can also be applied to a functional film pattern forming method in which a functional liquid material is deposited on the substrate 21 by a method other than direct drawing by a droplet discharge method in the first step. For example, the present invention is also applied to a functional film pattern forming method in which a functional liquid material is deposited on the substrate 21 by the microdispensing method or the screen printing method in the first step.

  In the above embodiment, the first step and the second step are repeated three times, so that one wiring pattern 19 is divided into three layers 19a to 19c. It is not limited to “3”. The present invention is widely applicable to a method in which the first step and the second step are repeated a plurality of times to form one functional film pattern (for example, the wiring pattern 19) in a plurality of layers.

  In the above embodiment, silver fine particles are used as the metal fine particles 31 as the functional material. However, as the metal fine particles, fine particles of gold, copper, aluminum or the like may be used in addition to silver.

  In the above embodiment, the case where the wiring pattern 19 is formed as an example of the functional film pattern has been described. However, the present invention forms an organic EL layer of an organic EL element, a color filter, a wiring pattern of an IC tag, and the like. Applicable to

  That is, the present invention relates to a functional liquid material in which metal fine particles (functionalized fine material) coated with a dispersant are dissolved in a solvent or dispersed in a dispersant, such as a metal wiring pattern. It can be widely applied to form a wiring pattern which is a functional film pattern by firing (drying and sintering). The present invention is not limited to this, but, depending on the material, such as an organic EL layer, a droplet in which a functional material is dissolved in a solvent is dried by heat generated by photothermal conversion to evaporate the solvent ( It can also be used for products with a functional film pattern.

  As described above, the present invention can be applied to both a functional film pattern formed by drying and a functional film pattern formed by baking (drying and sintering) depending on the mechanism (structure) of the functional film pattern to be formed. Is possible.

  In each of the above embodiments, the laser light irradiation head 24 uses the lens 52 as an optical element that focuses the laser light 50 on the film pattern 40 or 41 in a desired spot shape, but the present invention is not limited to this. Not. A diffractive optical element or a cylindrical lens that can arbitrarily change the spot shape and intensity of the laser light 50 irradiated to the film pattern 40 or 41 by appropriately setting the groove cutting method (groove shape) instead of the lens 52. Other optical elements may be used.

(A)-(C) Explanatory drawing which shows the procedure of the functional film pattern film-forming method which concerns on one Embodiment. The graph which shows the absorption spectrum of a functional material. (A) The absorption spectrum resulting from a solvent, (B) The absorption spectrum resulting from a dispersing agent, (C) The graph which shows the absorption spectrum resulting from microparticles | fine-particles, respectively. (A) An absorption spectrum in the early stage of firing, (B) an absorption spectrum in the middle stage of firing, and (C) an absorption spectrum in the later stage of firing. The perspective view which shows the personal computer as an electronic device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 19 ... Wiring pattern as a functional film pattern, 19a ... 1st layer, 19a-19c ... Layer, 21 ... Substrate, 30 ... Droplet, 31 ... Metal fine particle, 32 ... Solvent, 33 ... Dispersant, 40, 41 ... Film Pattern, 50 ... laser light, 55 ... reflecting surface.

Claims (5)

A first step of depositing a functional liquid material on a substrate to form a film pattern;
A second step of illuminating the film pattern with electromagnetic waves to develop functionality in the film pattern with heat generated by photothermal conversion;
Is repeated a plurality of times to form one functional film pattern by dividing it into a plurality of layers. The method for forming a functional film pattern according to claim 1,
The functional liquid material is obtained by coating a fine particle of a functional material with a dispersant and dissolving or dissolving in a solvent to form an ink or paste. In the step, when firing the film pattern with heat generated by the photothermal conversion to form each layer of the functional film pattern in order from the first layer, the first layer of the functional film pattern is formed by the firing to form the fine particles. A method for forming a functional film pattern, wherein the layers are baked to the extent that they melt and grow to form a reflective surface. The method for forming a functional film pattern according to claim 2,
The functional film pattern forming method, wherein the first layer of the functional film pattern is baked by increasing the input energy amount of the electromagnetic wave compared to the second and subsequent layers of the functional film pattern. In the functional film pattern film-forming method according to claim 2 or 3,
A method for forming a functional film pattern, wherein the functional material is finely divided into metal fine particles. An electronic apparatus comprising the functional film pattern formed by the functional film pattern forming method according to claim 1.

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