TW202239282A - Manufacturing method of conductive portion, manufacturing method of electronic component including conductive portion, manufacturing method of product assembled with electronic component including conductive portion, conductive portion, electronic component having conductive portion, and product incorporating electronic component including conductive portion - Google Patents

Abstract

To provide a manufacturing method for simply forming a conductive portion between a conductor having an insulating layer on the surface and another conductor. A manufacturing method of a conductive portion according to the present invention includes a first step of laminating a second conductor on a first conductor having an insulating layer on the surface, and a second step of melting the first conductor and the second conductor including the insulating layer to form a molten region and forming a hole surrounded by the molten region in the center of the molten region.

Description

Method of manufacturing conductive part, method of manufacturing electronic part including conductive part, method of manufacturing product assembled with electronic part including conductive part, conductive part, electronic part having conductive part, product assembling electronic part including conductive part

The present invention relates to a method of manufacturing a conductive structure using fired metal ink using metal ink and a conductive structure.

There is an electronic component that uses conductors as wires on a substrate. The material of the conductor is various, and sometimes titanium or aluminum and their alloys are used as the material of the conductor that forms a nano-scale natural oxide layer on the surface of the conductor. These metals are extremely easy to oxidize in the atmosphere to form a natural oxide layer. The native oxide layer is an insulator, which causes the part in contact with the atmosphere to be completely covered by the native oxide layer. Also, as in Patent Document 2, insulating layers such as SiO, SiN, and SiON may be formed by plasma CVD on wiring layers such as aluminum instead of natural oxide layers. Even if you want to overlap other wiring on the wiring or electrode with a natural oxide layer or insulating layer on the surface to make the two conductive, the simple overlapping will be hindered by the natural oxide layer or insulating layer and cannot be conducted (cannot become a conductive part). Therefore, as in Patent Document 1, the natural oxide layer is physically destroyed by scratching with a grinding needle, and other conducting wires are overlapped to form a conductive portion.

[Patent Document 1] Japanese Patent Laid-Open No. 2000-22306 [Patent Document 2] Japanese Patent No. 6711614

[Problem to be solved by the invention]

However, physical operations such as scratching using a grinding needle become difficult as the wire becomes thinner, and thus workability deteriorates. Moreover, even if the natural oxide layer is damaged to expose the metal, titanium or aluminum is easily oxidized in the atmosphere, resulting in the formation of the natural oxide layer again in a very short time. Therefore, it is difficult to reliably form a conductive portion having conductivity. The same applies to the insulating layer covering the surface of the metal wiring. When overlapping other wiring, the insulating layer needs to be removed in advance.

The object (problem) of the present invention is to provide a method for easily forming a conductive portion between a conductor having an insulating layer on its surface and another conductor, and to provide a new conductive portion. [Technical means to solve the problem]

The present invention solves the problem by setting the manufacturing method of the conductive part as follows, which includes: a first step of laminating a second conductive body on a first conductive body with an insulating layer on the surface; and a second step of including In the insulating layer, the first conductor and the second conductor are melted to form a fusion region, and a hole surrounded by the fusion region is formed in the center of the fusion region.

Also, another aspect of the present invention solves the problem by providing a conductive portion as follows: the conductive portion is characterized by having a first conductive body, a second conductive body, and a fusion region, the first conductive body has an insulating layer on the surface, and the aforementioned conductive portion has an insulating layer. 2 Conductive bulk layer on the first conductor, the melting region is a region obtained by melting the first conductor and the second conductor including the insulating layer, and the center of the melting region is surrounded by the melting region Surrounding hole. [Invention effect]

A conductive portion having conductivity can be easily formed between a conductor having an insulating layer on its surface and another conductor superimposed thereon.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same symbols in different drawings denote parts with the same functions, and overlapping descriptions in the respective drawings are appropriately omitted. In addition, some drawings are intentionally modified for the convenience of explanation, and are not drawn on an accurate scale.

[division before and after firing of metallic ink] Hereinafter, the metallic ink before firing is simply referred to as "metallic ink" and the metallic ink after firing is referred to as "fired metallic ink" for distinction.

[conductor] The term "conductor" includes wiring and electrodes.

[Meaning of parentheses attached to technical terms] Also, sometimes it is marked as "fired metal ink wire (second conductor)", etc., but (second conductor) in parentheses indicates a technical term used in the corresponding technical solution.

[Meaning of insulating layer] The insulating layer includes a natural oxide layer (insulating layer) formed by natural oxidation on the surface of a metal wire (first conductor) made of aluminum or the like as a main raw material. The insulating layer includes not only natural oxidizers, but also those produced by artificial processing. For example, a metal wire (first conductor) coated with an insulating layer made of other materials is also included in the present invention. In addition, in the present invention, the insulating layer also includes a layer having a higher resistance than the metal wire (first conductor) such as dirt adhering to the surface of the metal wire (first conductor).

[electronic parts] In the present invention, any element is included in the "electronic component" of the present invention as long as it is connected to another element by a wire. For example, circuit boards such as printed boards are also included in the "electronic component" of the present invention.

(example) Embodiment 1 shown in Figures 1 to 5 is when the first conductor A with a natural oxide layer (insulation layer B) 721 on the surface is used as the metal wire 72, and the second conductor C is used as the fired metal ink wire 27. , an example of forming a conductive portion 9 between two conductors. The materials of the first conductor A and the second conductor C are not limited, and an example in which the metallic ink 2 is used as the second conductor C is referred to as Example 1. It is used to explain how to use metallic ink 2 when repairing broken wires, etc. For example, wiring on a circuit board of a flat-panel display may be disconnected due to dust or dust adhering to the board during the manufacturing process. In this case, it can be repaired by making a detour circuit of metallic ink 2 as the second conductor C between the first conductors A before and after the disconnection. Embodiment 1 is an example, and the present invention does not exclude the use of the second conductor C made of a material different from the metal ink.

[Insulation] The main component of the metal wire (first conductor A) 72 is a metal that is naturally oxidized in the atmosphere to form a natural oxide layer (insulation layer B) 721 on the surface, such as aluminum or titanium.

[Metallic ink coating procedure] FIG. 1 is an explanatory diagram of the firing steps of the metallic ink 2 . FIG. 1(A) is a conceptual diagram of the firing steps of the firing metal ink conductive wire (second conductor C) 27 based on the scanning of the firing laser 3 . The substrate 7 has a metal wire (first conductor A) 72 disposed thereon. The metal wire (first conductor A) 72 is a wire mainly composed of aluminum, and a natural oxide layer (insulation layer B) 721 of several nanometers is formed on its surface. Next, the metal ink 2 is applied on the natural oxide layer (insulation layer B) 721 of the metal wire (first conductor A).

[Metallic Ink Firing Procedure] FIG. 1(B) is an enlarged view of metallic ink 2 . The metal ink 2 is made of highly conductive metal nanoparticles such as gold, silver, and copper, and dispersed in an organic solvent 26 . When metals are made into nanoparticles, their melting points drop sharply. The organic matter 25 is adsorbed on the surface of the metal nanoparticles 24 . With the organic matter 25 , the metal nanoparticles 24 are dispersed in the organic solvent 26 without agglomerating each other.

When the metal ink 2 is heated by irradiating the firing laser 3 or infrared rays, the organic solvent 26 evaporates, and the organic matter 25 on the surface of the metal nanoparticles 24 is detached, and the metal nanoparticles 24 are aggregated and melted to form a metal block. And has conductivity. The heating mechanism for firing is adequate. In Example 1, the firing laser 3 was used for firing. The absorption wavelength of the metallic ink 2 varies depending on the type and particle size of the metal, and in the metallic ink 2 including the metal nanoparticles 24 mainly composed of silver with a particle diameter of 20 nm used in Example 1, it is close to 400 nm. The firing laser 3 used in Example 1 is a continuous oscillation semiconductor laser having a wavelength close to the absorption wavelength.

FIG. 1(C) is an enlarged view of the sintered metal ink conductive wire (second conductor C) 27, and it can be seen that the metal nanoparticles 24 are fused together to form a metal block. Only the portion irradiated with the laser 3 for firing is fired to become a fired metal ink conductive line (second conductor C) 27, and becomes a fired metallic ink conductive line (second conductive body C) 27 having conductivity. As shown in Figure 1(A), the laser 3 for firing scans left and right along the metal ink 2 to fire the metal ink 2 as shown by the arrow, and burns the metal ink 2 in layers on the metal wire (first conductor A) 72 in the lower layer. Metallic ink wire (second conductor C) 27 .

[Metal ink coating step] and [Metal ink firing step] together become (the first step) layering and firing on the metal wire (first conductor A) 721 with a natural oxide layer (insulating layer B) 721 on the surface The step of metal ink wire (second conductor C) 27 .

From a structural point of view, the laminated structure has the following structure: it has a metal wire (first conductor A) 72 and a fired metal ink wire (second conductor C) 27, and the metal wire (first conductor A) 72 is on the surface. It has a natural oxide layer (insulation layer B) 721 , and the fired metal ink wire (second conductor C) 27 is laminated on the natural oxide layer (insulation layer B) 721 of the metal wire (first conductor A) 72 .

[Melting step] Fig. 2 is an explanatory diagram of a melting step. FIG. 2(A) is a cross-sectional view of the fired metallic ink conductor 27 of the fired metallic ink 2. FIG. Fig. 2(A) shows the state of finishing the firing in the above-mentioned [metal ink firing step]. At this point, the natural oxide layer (insulating layer B) 721 is sandwiched between the metal wire (first conductor A) 72 and the fired metal ink wire (second conductor C) 27, so there is no It has sufficient conductivity to function as the conductive portion 9 .

FIG. 2(B) is a cross-sectional view of a state in which a melting region 8 is produced by the melting laser 4 . The output of the melting laser 4 can be changed depending on the thickness of the metal wire (first conductor A) 72 and the fired metal ink wire (second conductor C) 27 , the type of metal, or the like. It is not recommended that the influence of the melting laser 4 affect the substrate 7 , and it is better to make the influence affect at least the output of the natural oxide layer (insulating layer B) 721 . More preferably, it is more preferable to affect the output extending beyond the natural oxide layer (insulating layer B) 721 to the metal wire (first conductor A) 72 .

Fusion destroys the natural oxide layer (insulation layer B) 721 with laser 4, except for the silver derived from the fired metal ink conductor (second conductor C) 27 and the aluminum derived from the metal conductor (first conductor A) 72 In addition, a fused region 8 mixed with alumina derived from the native oxide layer (insulation layer B) 721 is produced.

In the central portion irradiated with the laser beam 4 for melting, a hole 74 which is a trace of metal vaporization is opened as shown in the figure. The melted region 8 indicated by hatching is formed on the inner wall portion of the hole 74 . The molten region 8 contains a large amount of highly conductive aluminum and silver, and is mixed with a natural oxide layer (insulating layer B) 721 of at most several nanometers, so it is a region with remarkably high conductivity. As a result, by irradiating the laser 4 for fusion, the following steps are performed: (second step) the metal wire (first conductor A) 72 and the fired metal ink wire including the natural oxide layer (insulation layer B) 721 The (second conductor C) 27 is melted to form a molten region, and a hole 74 surrounded by the molten region 8 is formed in the center of the molten region 8 .

As explained above, the fusion region 8 where the natural oxide layer (insulation layer B) 721, the fired metal ink conductor (second conductor C) 27 and the metal conductor (first conductor A) 72 are melted is formed, and in the fusion region The center of 8 has a hole 74 surrounded by the molten region 8 .

[Other states of the melting step] FIG. 2(C) is a cross-sectional view of the case where the pulse energy of the melting laser 4 is changed to irradiate three locations, and the depth affected by the melting laser 4 is changed. (In addition, Figure 2 is a conceptual diagram, and low output, middle output, and high output are comparisons of pulse energy in the figure.)

In FIG. 2(C)(a), the melting laser 4 with low output pulse energy is irradiated. The molten region 8 is limited to the range of the fired metal ink lead (second conductor C) 27, and the conduction between the metal lead (first conductor A) 72 and the fired metal ink lead (second conductor C) 27 cannot be expected. sexual enhancement.

Also, in FIG. 2(C)(b), the laser 4 for melting is output with pulse energy during irradiation. The influence of the laser 4 for melting spreads to the vicinity of the natural oxide layer (insulation layer B) 721, and the conduction between the metal wire (first conductor A) 72 and the fired metal ink wire (second conductor C) 27 can be expected However, the thickness of the fired metal ink conductive wire (second conductor C) 27 is not uniform, so the conductivity may not be improved to the expected level.

In FIG. 2(C)(c), the melting laser 4 with high output pulse energy is irradiated. The molten area 8 is formed beyond the natural oxide layer (insulation layer B) 721 of the metal wire (the first conductor A) 72, and the metal wire (the first conductor A) 72 and the fired metal ink wire (the second conductor C) 27 The conductivity between them is definitely improved.

The metal ink 2 is applied to each place where the conductive part 9 is formed, and the application conditions of each part are not completely the same, so the conditions (thickness, etc.) for firing the metal ink wire (second conductor C) 27 are not uniform. Therefore, by changing the pulse energy to 2 or more places, preferably 3 places, the melting laser 4 is irradiated, so that the conductivity can be reliably ensured without performing experiments to determine the output that meets the conditions for each conductive part formation site. . In addition, the pulse width and the number of irradiations can also be changed.

In summary, in FIG. 2( c ), three locations were irradiated by changing the pulse energy of the laser 4 for melting, but it is only necessary to irradiate two or more locations. When making two or more molten regions 8 with different depths, only a third step for making other molten regions with different depths at different positions from the molten regions formed in the second step is added after the second step. Steps will do.

In addition, two or more melting regions are provided, and the depths of the melting regions are different, whereby conductivity can be ensured reliably.

In the embodiment, the melting laser 4 set to form the hole 74 by pulse energy is used. By forming the hole 74 surrounded by the molten region 8 at the center of the molten region 8, the depth at which the molten region 8 is formed can be known. Also, by forming the hole 74, heat is released through the hole 74, and the melting region 8 can be cooled rapidly. Usually, thermal energy affects components near the melting region 8 , especially when laser irradiation is performed on the substrate 7 near the melting region 8 such as an organic layer, the organic layer may be deteriorated. Furthermore, like the present invention, the melting laser 4 configured to irradiate a nanosecond pulse laser with high output to form the hole 74 forms the minute hole 74 penetrating the natural oxide layer (insulating layer B) 721 . The heat of the melting region 8 is also dissipated from the holes 74 to accelerate the cooling rate, and the influence of the heat can be suppressed only in an extremely small area around the melting region 8 .

On the other hand, when using the welding laser 41 in which the hole 74 is not formed, as the fusion region 8 expands, the range affected by the heat also expands.

FIG. 3 corresponding to the comparative experiment is an explanatory diagram of the range affected by the development of the irradiation process and the influence of heat in the case of laser irradiation with the welding laser 41 not forming the hole 74 . Fig. 3(A) is the state diagram immediately after irradiation, Fig. 3(B) is the state diagram where the melting region 8 does not reach the natural oxide layer (insulation layer B) 721, and Fig. 3(C) is the melting region 8 beyond the natural oxide layer (Insulation layer B) State diagram of 721.

As in FIG. 3(A) , the molten region 8 immediately after irradiation is small, but heat diffuses by heat conduction from the region irradiated with the welding laser 41 where the holes 74 are not formed. If the irradiation is continued, the molten region 8 gradually expands as shown in FIG. 3(B). If the irradiation is continued further, the heat conduction will continue, and then the molten region 8 will expand, and as shown in FIG. The insulating layer B) 721 melts away. The temperature of the melting region 8 reaches the melting point of the metal and is extremely high, and the surroundings of the melting region 8 become a region 412 affected by heat through heat conduction. At this time, the heat dissipation is only carried out from the surface of the fired metal ink lead (second conductor C) 27, and the larger the volume of the melting region 8, the more unable to catch up with the heat dissipation proportional to the surface area. The area 412 affected by the thermal influence is more extended than the high temperature metal that resides in the molten area 8 of increased volume.

In Embodiment 1, the hole 74 is opened in the center of the melting region 8 as in FIG. 2, so the metal of the melting region 8 is rapidly cooled. Using the melting laser 4 with the hole 74 in this way can significantly reduce the area 412 affected by the heat influence compared to using the welding laser 41 without the hole 74 .

Hereinafter, experimental examples of the present invention will be described. (Experiment 1: An experiment showing the relationship between resistance and pulse energy) Experiment 1 is an experiment to study how the resistance changes before and after the destruction of the natural oxide layer (insulation layer B) 721 by changing the depth of the melting region 8 . In Experiment 1, as a sample for irradiation with the soldering laser 4 , a metal ink 2 was coated and fired on a metal wire 72 on a substrate 7 to form a fired metal ink wire 27 . Thereafter, the conditions were changed, and the sample was irradiated with the laser 4 for melting. In order to change the depth of the melting region 8 formed by the melting laser 4 , the pulse energy of the melting laser 4 was changed to four conditions of 100, 200, 250, and 300 μJ. In addition, the conditions other than the pulse energy were set to the same conditions.

The conditions of Experiment 1 will be described in advance. (1) Laser for melting 4 Wavelength 532nm Pulse width 10ns Pulse times 1 time Melt processing set size 1μｍ×1μｍ Pulse energy Experiments were performed at 100, 200, 250, 300 μJ (see Figure 4) (2) Metal wire (first conductor A) 72 Type of metal Aluminum Wiring Width ･5μ㎜ (3) Firing metal ink wire (second conductor C) 27 Type of metal Silver (nanoparticles) Wiring thickness 0.4μｍ Based on the above experimental conditions, samples were produced with varying pulse energy of the melting laser 4, and the resistance between the metal wire (first conductor A) 72 and the fired metal ink wire (second conductor C) 27 was measured. The result is shown in Figure 4.

When the pulse energy was 100 μJ, the resistance was 340Ω on average, and the conductivity was not improved compared to before irradiation with the melting laser 4 . It is presumed that the influence of the melting laser 4 is limited to the firing range of the metallic ink lead wire (second conductor C) 27 as shown in FIG. 2(C)(a).

At a pulse energy of 200 μJ, the resistance averaged 50 Ω, and a significant increase in conductivity was observed. It is estimated that the influence of the melting laser 4 is limited to the vicinity of the natural oxide layer (insulating layer B) 721 as in FIG. 2(C)(b).

When the pulse energy is 250μJ and 300μJ, the average resistance decreases sharply close to 0Ω. It is estimated that the natural oxide layer (insulation layer B) 721 is melted, and the influence of the laser 4 for melting is estimated to affect the metal wire (first conductor A) 72 as shown in FIG. 2(C)(c). Moreover, when the pulse energy is 200μJ, 30Ω remains on one side of the error bar (3σ), and about 60Ω remains on both sides. There is a large deviation in the observed resistance, but when the pulse energy is 250μJ and 300μJ, the error bar (3σ) is 2 ~3Ω.

This shows that the influence of the laser beam 4 for fusing spreads to a portion where conductivity can be reliably ensured. Furthermore, it shows that the electrical resistance is sufficiently small, and the conductive portion 9 is stably formed with little variation.

(Experiment 2: Confirmation of the melting region) In order to confirm the existence of the molten region 8 , Experiment 2 of scanning electron microscope photography of the conductive portion 9 was carried out. 5 is a scanning electron micrograph of the conductive portion 9 , FIG. 5(A) is a scanning electron micrograph of the conductive portion 9 , and FIG. 5(B) is an explanatory view of the scanning electron micrograph of FIG. 5(A).

Photographic samples were prepared and photographed as follows. (1) The substrate 7 having the conductive portion 9 produced as above was used as a sample, and it was covered with the protective film 73 for pre-processing for subsequent electron beam cutting. (2) Using an electron beam, each substrate 7 is cut and a section is cut. (3) The above-prepared samples were photographed with a scanning electron microscope from the angle of knowing the cross-section.

The protective film 73 shaded in FIG. 5(B) is covered when preparing the sample, and does not exist on the original conductive portion 9 . There is a natural oxide layer (insulating layer B) 721 on the surface of the metal wire (first conductor A) 72, but it is several nanometers thick, and was not photographed at this magnification.

A hole 74 is formed in the region irradiated with the laser 4 for melting. On the side of the hole 74, the boundary between the fired metal ink lead (second conductor C) 27 and the metal lead (first conductor A) 72 that should exist is blurred or completely disappeared. It can be seen that the metal wire (first conductor A) 72 including the natural oxide layer (insulation layer B) 721 and the fired metal ink wire (second conductor C) 27 are melted to form the molten region 8 .

(Summary of Experiment 1 and Experiment 2) From the above experiments, it has been confirmed that the metal wire (first conductor A) 72 including the natural oxide layer (insulation layer B) 721 and the fired metal ink wire (second conductor C) are ) 27 is melted to form a molten region 8 . Furthermore, it was confirmed that the resistance between the metal lead wire (first conductor A) 72 and the fired metal ink lead wire (second conductor C) 27 was significantly lowered by irradiation of the melting laser 4, and the resistance value was obtained. results with less deviation. The present invention can be practically used because there is little variation in resistance value.

(Example 2) Embodiment 2 is an application example of the present invention. 6 is an explanatory diagram of Embodiment 2, FIG. 6(A) is a plan view of the substrate 7 of the TFT liquid crystal panel, and FIG. 6(B) is an enlarged view of the detour circuit provided in FIG. 6(A).

On the substrate 7 of the TFT liquid crystal panel of LCD (Liquid Crystal Display), an electric field effect transistor 12 is installed, and a metal wire (first conductor A) 72 mainly composed of aluminum is arranged. If there is a defect (disconnection) 722 in one of the wirings, it usually leads to discarding it as a defective product.

The substrate 7 with a defect (disconnection) 722 is repaired by the detour circuit 76 fabricated using the fired metal ink conductive wire (second conductor C) 27, and the product yield is improved.

There are many possibilities for the cause of the defect (disconnection) 722, and the main reason is the adhesion of garbage. It is also possible to connect the defect (broken line) 722 directly and in a straight line at the shortest distance, but since there is a possibility that garbage or the like remains, the detour circuit 76 is reluctantly provided. Of course, the defects (broken lines) 722 can also be repaired by directly and straightly connecting them with the shortest distance.

The detour circuit 76 using the metallic ink 2 of silver is fired with the laser 3 for firing (not shown), and becomes the fired metallic ink lead (second conductor C) 27 . In this way, the part of the conductive part 9 becomes the laminated substrate 7, metal wire (first conductor A) 72, natural oxide layer (insulation layer B) 721, fired metal ink wire (second conductor C) in order from below. ) The structure of 27.

The laser 4 for melting is irradiated to three places of each conductive part 9 while changing the intensity of the pulse energy. (See Figure 2(C))

The conductive portion 9 is formed in the molten region 8 formed around the three holes 74 . As long as any one of the 3 melting regions 8 that change the intensity of the pulse energy reaches the natural oxide layer (insulation layer B) 721, the metal wire (the first conductor A) 72 and the fired metal ink wire (the second conductor C) ) The resistance between 27 is reduced to a level that does not affect the operation of the TFT liquid crystal panel. In addition, a hole 74 surrounded by the molten region 8 is formed in the center of the molten region 8, so that the molten metal in the molten region 8 dissipates heat from the hole 74 and cools rapidly, thereby reducing the influence of heat around the molten region 8.

This invention can use the board|substrate (electronic component) of a TFT liquid crystal panel as a manufacturing method like Example 2. Furthermore, the present invention can provide a substrate (electronic component) of a TFT liquid crystal panel having a conductive portion 9 provided with a metal wire (first conductor A) 72 including a natural oxide layer (insulating layer B) 721 and Burn the molten area 8 where the metal ink lead wire (second conductor C) 27 is melted.

Furthermore, it can also be used as the manufacturing method of the product called a TFT liquid crystal panel which assembles the board|substrate (electronic part) of the TFT liquid crystal panel provided above, and other components. Furthermore, it is also possible to provide a product called a liquid crystal display by assembling the TFT liquid crystal panel (electronic component) provided above and other components. In addition, the specific content and manufacturing methods of the TFT liquid crystal panel and liquid crystal display technology are widely known, so details will not be repeated here.

(Example 3) FIG. 7 is a cross-sectional view of the conductive portion 9 of the third embodiment. Embodiment 1 and Embodiment 2 are examples in which the natural oxide layer 721 is used as the insulating layer B. Example 3 is a state in which an insulating layer B is artificially formed on the surface of the metal wire (the first conductor A). Also, the second conductor C may not be a fired metal ink lead. Furthermore, the same metal material may be used for the first conductor A and the second conductor C.

As an example, the example of the laminated circuit board 5 is shown. There are many layers on the laminated circuit board 5 such as the first conductor A, the insulating layer B, the second conductor C, the insulating layer B, the first conductor A, the insulating layer B, and the second conductor C sandwiching the insulating layer B. Conductor.

By irradiating the laminated conductor with laser 4 for melting, conductive portion 9 is formed in fusion region 8 where first conductor A, second conductor C and insulating layer B are melted. The melting region 8 becomes a conductive part 9, which can conduct all the laminated conductors.

Above, the embodiments 1 to 3 of the present invention have been described in detail with reference to the drawings, but the specific configuration is not limited to these embodiments, and even if there are design changes within the scope of the scope of the present invention, they are also included in this document. inventing. In addition, as long as there is no particular conflict or problem in the above-mentioned respective embodiments in terms of their purpose, configuration, etc., each other's technology can be used and combined.

A: The first conductor B: insulating layer C: Second conductor 2: Metal ink 24: Metal nanoparticles 25: Organic matter 26: Organic solvent 27:Fired metal ink wire (second conductor) 27(C): Firing metal ink wires 3:Laser for firing 4: Laser for melting 41:Laser for welding 412:The area affected by the influence of heat 5: Laminated circuit substrate 7: Substrate 72: Metal wire (the first conductor) 72 (A): metal wire (first conductor A) 721: natural oxide layer (insulation layer) 721 (B): natural oxide layer (insulation layer B) 722: defect (disconnection) 73: Protective film 74: hole 75: Electric field effect transistor 76: Detour circuit 8: Molten area 9: Conductive part

Fig. 1 is an explanatory diagram of the firing steps of metallic ink. FIG. 1(A) is a conceptual diagram of firing steps of firing metal ink wires based on scanning of firing lasers. Figure 1(B) is an enlarged view of metallic ink. Figure 1(C) is an enlarged view of fired metallic ink. Fig. 2 is an explanatory diagram of a melting step. Fig. 2(A) is a cross-sectional view of a fired metal ink lead obtained by firing the metal ink. Fig. 2(B) is a cross-sectional view of a state in which a fusion region is produced by a fusion laser. Fig. 2(C) is a cross-sectional view of the case where the pulse energy of the melting laser is changed to irradiate three places, and the depth of influence of the melting laser is changed. FIG. 3 is an explanatory diagram of the range affected by the progress of the irradiation process and the influence of heat in the case of laser irradiation with a welding laser that does not form holes. Fig. 3(A) is a state diagram immediately after irradiation. Figure 3(B) is a state diagram of the molten region not reaching the natural oxide layer. Figure 3(C) is a state diagram of the molten region beyond the natural oxide layer. Figure 4 is the result of the conductivity test. Fig. 5 is a photo of the conductive part. FIG. 5(A) is a scanning electron micrograph of a cross section of an electroconductive portion. FIG. 5(B) is an explanatory view of the scanning electron micrograph of FIG. 5(A). FIG. 6 is an explanatory diagram of Embodiment 2. FIG. FIG. 6(A) is a plan view of a TFT liquid crystal panel. FIG. 6(B) is an enlarged view of the detour circuit in FIG. 6(A). FIG. 7 is a cross-sectional view of the conductive part of the third embodiment.

4: Laser for melting

7: Substrate

8: Molten area

9: Conductive part

27(C): Firing metal ink wire

72(A): Metal wire (first conductor A)

74: hole

721(B): Natural oxide layer (insulating layer B)

Claims (10)

A method of manufacturing a conductive part, comprising: Step 1, which is to build up a second conductor on the first conductor with an insulating layer on the surface; and In the second step, the first conductor and the second conductor including the insulating layer are melted to form a fusion region, and a hole surrounded by the fusion region is formed in the center of the fusion region. The manufacturing method of the conductive part as claimed in item 1, after the aforementioned second step, comprising: In the third step, another molten region having a different depth from the molten region formed in the second step is formed at a position different from that of the molten region formed in the second step. The manufacturing method of the conductive part according to claim 1 or 2, wherein The aforementioned insulating layer is a natural oxide layer of the oxidized metal of the aforementioned first electrical conductor, The aforementioned second conductor is a fired metal ink conductor obtained by firing the metal ink. A method of manufacturing an electronic component, characterized in that, The aforementioned first electrical conductor is arranged on the substrate, and the conductive part according to any one of claims 1 to 3 is fabricated on the aforementioned substrate. A method for manufacturing a product, comprising assembling the electronic component of claim 4 with other electronic components to produce the product. A conductive part, characterized in that, Equipped with a first conductor, a second conductor and a fusion zone, The first conductor has an insulating layer on the surface, The aforementioned second conductive volume layer is on the aforementioned first electrical conductor, The molten region is a region obtained by melting the first conductor and the second conductor including the insulating layer, and has a hole surrounded by the molten region at the center of the molten region. Such as the conductive part of claim 6, wherein There are two or more melting regions, and the melting regions have different depths. Such as the conductive part of claim 6 or 7, wherein The aforementioned insulating layer is derived from the natural oxide layer of the metal of the aforementioned first electrical conductor, The fired metal ink lead obtained by firing the metal ink of the aforementioned second conductive system. An electronic component, wherein the aforementioned first conductor is arranged on a substrate, and has a conductive portion according to claim 6 or 7. A kind of product, it is assembled with the electronic part as claim item 9.

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