JP4362742B2 - Method for solidifying paste-like metal particle composition, method for joining metal members, and method for producing printed wiring board - Google Patents

Description

The present invention, by applying a pressurized while ultrasonic vibration to Lupe paste-like metal particle composition such from metal particles and volatile dispersion medium, in particular by applying pressure, while heating ultrasonic vibration A method of sintering and solidifying metal particles by means of: interposing a paste-like metal particle composition between a plurality of metal members, and applying ultrasonic vibration while applying pressure; A method of joining metal members by sintering and solidifying metal particles by applying sonic vibration; and applying ultrasonic vibration while pressing a paste-like metal particle composition applied on a substrate In particular, the present invention relates to a method of manufacturing a printed wiring board in which metal wiring is formed by sintering and solidifying metal particles by applying ultrasonic vibration while applying pressure and heating.

The conductive paste is a paste mainly containing fine metal powder as a solid content, and is used as a conductive path, for example, when forming a conductive wiring of a printed wiring board. Further, in a double-sided printed wiring board and a build-up multilayer printed wiring board, a method of filling through holes with conductive silver paste and connecting the wiring patterns of each layer is adopted. A conductive paste for forming thick film conductor wiring on a ceramic substrate is also known.

In general, fine metal powders such as gold, platinum, silver, and palladium that are not oxidized in air are used as fine metal powders, but recently, by adopting a method of firing in a non-oxidizing atmosphere. Base metals such as nickel and copper are also used. The conductive paste is applied onto a substrate (substrate) by screen printing, gravure printing, coating, or the like. The coating film is heat-treated after drying to become a conductive film. Conventional conductive pastes are roughly classified into a high temperature sintering type, a thermosetting type, and a low temperature sintering type from the viewpoint of a solidification method.

For example, in Patent Document 1 relating to a high-temperature sintered conductive paste, a paste-like conductive resin composition containing a conductive metal powder (for example, copper powder) is applied to a substrate and cured, and 350 ° C. over 20 minutes. The temperature is raised to 90 ° C. and held for 20 minutes to thermally decompose the resin, and then the temperature is raised to 900 ° C. and held for 30 minutes to sinter the copper powder.

High-temperature sintering type conductive paste requires extremely high temperature and long time to thermally decompose resin and sinter metal powder, low production efficiency for mass production and high energy cost. There is a problem that there is.

In Patent Document 2 relating to a thermosetting conductive paste, a conductive paste made of a polyimide varnish containing scaly silver powder is applied to a polyimide film, held at 120 ° C. for 30 minutes and dried, and a dry film is 170 ° C. For 30 minutes and then at 230 ° C. for 10 minutes to obtain a conductive film.

The thermosetting conductive paste has a lower curing temperature than the high-temperature sintered conductive paste, but it takes a long time to cure, so there is a problem that the production efficiency is low for mass production and the energy cost is great. is there. In addition, since the resin that is inherently electrically insulating remains as a binder, there is a problem that the electrical conductivity cannot be increased too much.

In Patent Document 3, in a flip-chip mounting method in which an electrode of a wiring element and an electrode of a substrate are opposed to each other and the electrodes are electrically and mechanically connected, at least one of the wiring element electrode or the substrate electrode is Supplying a metal paste in which metal fine particles having an average particle diameter of 1 to 100 nm are dispersed in a solvent, aligning the wiring element electrode and the substrate electrode with the metal paste in between, and The step of activating the electrode surface at the interface with the metal paste by applying ultrasonic vibration to at least one of the wiring element side and the substrate side, and the melting point of the metal fine particles above the boiling point of the solvent constituting the metal paste By heating at the following temperature (100 ° C. to 300 ° C.) for 5 to 60 minutes, the solvent is evaporated to electrically connect the wiring element electrode and the substrate electrode. Characterized by a step of connecting micro-mechanically. Since this mounting method is sintered at 100 ° C. to 300 ° C., it can be said to be a low temperature sintering type. The ultrasonic vibration in the flip-chip mounting method is performed to remove oxides and contaminants on the electrode surface and to activate the electrode surface, and joins metal particles in the metal paste and metal on the electrode surface. In addition, the sintering of the metal particles is performed by a heating process.

Although this mounting method has a heating temperature lower than that of the high-temperature sintered conductive paste, it takes a long time, so that there is a problem in that the production efficiency is low and the energy cost is high for mass production.

In addition, there is a problem in that ultrasonic vibration needs to be applied as a pretreatment for removing oxide on the electrode or the like, which is an adherend, and a plurality of processes are required.

Further, in order to improve the sinterability, nano-level metal particles having an average particle diameter of 1 to 100 nm with high surface activity are required. However, metal fine particles having an average particle diameter of 1 to 100 nm have a problem that they are easily aggregated at room temperature in a fine powder form or in a solvent and storage stability is poor. Furthermore, the metal fine particles having an average particle diameter of 1 to 100 nm have a problem that the average particle diameter is extremely expensive as compared with metal particles having an average particle diameter of 100 nm, that is, larger than 0.1 μm.

JP 2002-97215 A JP 2004-39379 A JP 2004-116612 A

As a result of diligent research to develop a solidification method for a paste-like metal particle composition that does not have the above-mentioned problems, the inventors of the present invention have achieved a short by applying ultrasonic vibration while applying pressure to a specific paste-like metal particle composition. The metal particles were sintered with time, and the paste-like metal particle composition was found to solidify, and the present invention was completed. How to use the pasty metal particle composition, joining efficiently metallic member in a short time; object of the present invention, a method of efficiently solidify in a short time pasty metal particle composition and, using the pasty metal particle composition in a short time efficiently is to provide a method for manufacturing a printed wiring board forming a metal wiring.

This object is achieved,
[1 ] A paste-like metal particle composition comprising (A) metal particles having an average particle size of greater than 0.1 μm and 30 μm or less and a carbon content of 2.0% by weight or less and (B) a volatile dispersion medium. A method for solidifying a paste-like metal particle composition, wherein the metal particles are sintered together by applying ultrasonic vibration having a frequency of 2 kHz or higher while applying pressure.
[ 2 ] Applying ultrasonic vibration having a frequency of 2 kHz or more while applying pressure and heating at a temperature higher than normal temperature and not higher than 400 ° C. and lower than the melting point of the metal particles, [ 1 ] The solidification method of the paste-like metal particle composition of description.
[ 3 ] The method for solidifying a paste-like metal particle composition according to [ 1 ] or [ 2 ], wherein the amplitude of ultrasonic vibration is 0.1 to 40 μm.
[ 4 ] The method for solidifying a paste-like metal particle composition according to [ 1 ] or [ 2 ], wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more.
[ 5 ] The method for solidifying a paste-like metal particle composition according to [ 3 ], wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more.
[ 6 ] Between a plurality of metal members, (A) metal particles having an average particle size of more than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight, and (B) a volatile dispersion medium, A method for joining metal members, comprising interposing a paste-like metal particle composition comprising: and applying ultrasonic vibration having a frequency of 2 kHz or more while applying pressure to sinter the metal particles.
[7] while pressing, and while heating at a temperature below the melting point of at most 400 ° C. higher than the normal temperature the metal particles, and applying the ultrasonic vibration frequency is not less than 2 kHz, [6 ] The joining method of the metal members of description.
[ 8 ] The method for joining metal members according to [ 6 ], wherein the metal member is a metal member of an electronic component or an electrical component.
[ 9 ] The method for joining metal members according to [ 7 ], wherein the metal member is a metal member of an electronic component or an electrical component.
[ 10 ] The method for joining metal members according to any one of [ 6 ] to [ 9 ], wherein the amplitude of the ultrasonic vibration is 0.1 to 40 [mu] m.
[ 11 ] The method for joining metal members according to any one of [ 6 ] to [ 9 ], wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more.
[ 12 ] The method for joining metal members according to [ 10 ], wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more.
[ 13 ] A paste-like metal particle composition comprising (A) metal particles having an average particle size of more than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight, and (B) a volatile dispersion medium. Is applied onto a substrate coated with a curable adhesive, and the metal particles are sintered by applying ultrasonic vibration having a frequency of 2 kHz or higher while applying pressure to the paste-like metal particle composition, A method of manufacturing a printed wiring board, wherein the metal wiring is formed by curing the adhesive.
[14] while pressing, and while heating at a temperature below the melting point of at most 400 ° C. higher than the normal temperature the metal particles, and applying the ultrasonic vibration frequency is not less than 2 kHz, [13 ] The printed wiring board manufacturing method of description.
[ 15 ] The method for producing a printed wiring board according to [ 13 ] or [ 14 ], wherein the amplitude of the ultrasonic vibration is 0.1 to 40 μm.
[ 16 ] The method for producing a printed wiring board according to [ 13 ] or [ 14 ], wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more.
[ 17 ] The method for producing a printed wiring board according to [ 15 ], wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more. Achieved by;

In the method for solidifying a paste-like metal particle composition of the present invention, ultrasonic vibration having a frequency of 2 kHz or higher is applied while applying pressure, in particular, applying pressure and heating, so that the metal in the composition can be obtained in a very short time. The particles are sintered to obtain a solid metal having excellent strength, conductivity, and thermal conductivity. In particular, while applying pressure and applying ultrasonic vibration having a frequency of 2 kHz or higher while heating at a temperature higher than normal temperature and not higher than 400 ° C. and lower than the melting point of the metal particles, the volatile dispersion medium can be efficiently produced. It volatilizes and the metal particles in the composition sinter in a very short time, and a solid metal having excellent strength, conductivity and thermal conductivity is obtained.

In the metal member joining method of the present invention, the paste-like metal particle composition is interposed between a plurality of metal members, and ultrasonic vibration having a frequency of 2 kHz or more is applied while applying pressure. The metal particles in the composition are sintered, and a plurality of metal members are firmly bonded with high durability. In particular, while applying pressure and applying ultrasonic vibration having a frequency of 2 kHz or higher while heating at a temperature higher than room temperature and not higher than 400 ° C. and lower than the melting point of the metal particles, the volatile dispersion medium is efficiently volatilized. The metal particles in the composition are sintered in an extremely short time, and a plurality of metal members are firmly bonded with high durability.

In the method for producing a printed wiring board of the present invention, a paste-like metal particle composition is applied onto a substrate coated with a curable adhesive, and the frequency is 2 kHz or more while applying pressure to the paste-like metal particle composition. Since ultrasonic vibration is applied, the metal particles are sintered in an extremely short time, and a metal wiring having excellent wear resistance, adhesion, conductivity, and thermal conductivity is formed. In particular, while applying pressure and applying ultrasonic vibration having a frequency of 2 kHz or higher while heating at a temperature higher than normal temperature and not higher than 400 ° C. and lower than the melting point of the metal particles, the volatile dispersion medium can be efficiently produced. It is possible to produce a printed wiring board having a metal wiring which is volatilized and the metal particles are sintered in an extremely short time and has excellent wear resistance, adhesion, conductivity, and thermal conductivity. Moreover, a circuit board can be manufactured by mounting a chip or the like on the printed wiring board by the bonding method.

The solidification method of the paste-like metal particle composition of the present invention, the method of joining metal members, and the method of manufacturing a printed wiring board all can shorten the required time, so that the production efficiency is high and the energy cost is high. Can also save a lot compared to the past.

In order to fabricate the test body A for fixing strength measurement in the examples, the ultrasonic vibration is applied to the paste-like metal particle composition 4 between the chip capacitor terminal electrode 3 and the substrate land (pad) portion 5. FIG.

Explanation of symbols

A Bonding strength test specimen B Ultrasonic thermocompression bonding equipment (probe)
1 Glass fiber reinforced epoxy resin substrate 2 2012 chip capacitor 3 2012 chip capacitor terminal electrode 4 Paste-like metal particle composition 5 Substrate land (pad) part

The paste-like metal particle composition of the present invention comprises (A) metal particles having an average particle size of greater than 0.1 μm and 30 μm or less and (B) a volatile dispersion medium. When ultrasonic vibration having a frequency of 2 kHz or higher is applied while heating, the metal particles are sintered and solidified in an extremely short time.
The average particle diameter of the metal particles (A) is an average particle diameter of primary particles obtained by laser diffraction or image analysis of an electron micrograph. When the average particle size exceeds 30 μm, the sinterability between the metal particles decreases, and it is difficult to obtain excellent strength, conductivity, thermal conductivity, and adhesion. Therefore, the average particle diameter is 30 μm or less, preferably 10 μm or less, more preferably 6 μm or less. However, when the so-called nano-size is 0.1 μm or less, the surface activity is too strong and the storage stability of the paste-like metal particle composition may be lowered, so that it is larger than 0.1 μm, preferably 0.8. 2 μm or more.

The metal particles (A) are required to be solid at room temperature, and are preferably selected from gold, silver, copper, aluminum, nickel, and tin, which have particularly high conductivity and thermal conductivity. Moreover, the alloy which consists of those metals, or the metal by which the surface was coated with those metals may be sufficient. In the case of an alloy, the content of gold, silver, copper, aluminum, nickel, or tin is preferably 50% or more. The shape of the metal particles is spherical, flake shaped, needle shaped, square shaped, dendritic shaped, granular, irregular shaped, teardrop shaped plate shaped, plate shaped, ultrathin plate shaped, hexagonal plate shaped, columnar, rod shaped, porous, Examples include fiber, lump, sea surface, corner and round. Preferred are flakes, needles, horns, dendrites, granules, irregular shapes, tear drops, plates, ultrathin plates, hexagons, more preferably spheres, flakes or granules. .

The metal particles (A) may adhere to organic compounds during the production process. If the adhesion amount is too large, the sinterability may be adversely affected, so the carbon content is 2.0% by weight or less, preferably 1.0% by weight or less. Here, the amount of carbon is converted by converting the carbon in the organic compound adhering to the metal particles to carbon dioxide by heating the metal particles in an oxygen stream and measuring the amount of carbon dioxide by the infrared absorption spectrum method. The amount of carbon was calculated. The surface of the metal particles (A) may be slightly oxidized. However, when the surface is covered with an oxide film other than silver oxide (for example, copper oxide, aluminum oxide, nickel oxide, tin oxide, etc.), this oxidation It is preferable to use after removing the film. This is because these oxide films are chemically stable and the sinterability between metal particles is low. The method for removing these oxide films is not limited. For example, a reduction treatment in a hydrogen atmosphere, a reduction treatment by adding a hydrogen generating material, a reduction treatment by a known reducing agent, a reduction treatment by adding a known reducing agent, etc. Illustrated. Since silver oxide is easily reduced by heating, the presence of silver oxide on the silver particle surface is optional.

The paste-like metal particle composition of the present invention is a mixture of metal particles (A) and a volatile dispersion medium (B), and the powder-like metal particles (A) are pasted by the action of the volatile dispersion medium (B). It has become. By making it into a paste, it can be discharged in a thin line from a cylinder or nozzle, and it can be easily applied by printing with a metal mask, and can be easily applied to the shape of an electrode. The reason for using a volatile dispersion medium instead of a non-volatile dispersion medium is that when the metal particles (A) are sintered by ultrasonic vibration, if the dispersion medium is volatilized in advance, the metal particles (A) are sintered. This is because the strength, conductivity, and thermal conductivity of the solid metal are likely to increase. The volatile dispersion medium (B) does not alter the surface of the metal particles and has a boiling point of 60 ° C. or higher and preferably 300 ° C. or lower. When the boiling point is less than 60 ° C., the solvent easily evaporates during the operation of preparing the paste-like metal particle composition, and when the boiling point is higher than 300 ° C., the volatile dispersion is performed even after the metal particles (A) are sintered. This is because the medium may remain. As such a volatile dispersion medium (B), water; volatile monohydric alcohols such as ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, and benzyl alcohol Other volatile alcohols; volatile aliphatic hydrocarbons such as lower n-paraffins and lower isoparaffins; volatile aromatic hydrocarbons such as toluene and xylene; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diacetone alcohol ( 4-hydroxy-4-methyl-2-pentanone), 2-octanone, isophorone (3,5,5-trimethyl-2-cyclohexen-1-one), dibutyl ketone (2,6-dimethyl-4-heptanone) Etc. Volatile ketones; Volatile acetates such as ethyl acetate and butyl acetate; Volatile aliphatic carboxylic esters such as methyl butyrate, methyl hexanoate, methyl octoate and methyl decanoate; Tetrahydrofuran and methyl cellosolve Volatile ethers such as propylene bricol monomethyl ether, methylmethoxybutanol and butyl carbitol; low molecular weight volatile silicone oils and volatile organic modified silicone oils; and the like, in particular butyl alcohol, pentyl alcohol, hexyl alcohol A volatile monohydric alcohol such as heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol or benzyl alcohol is preferred. These volatile monohydric alcohols having 4 to 10 carbon atoms are excellent in printability with a metal mask, extrudability from a syringe, and dischargeability when made into a paste-like metal particle composition, and have appropriate volatilization. It is because it has sex. Then volatile aliphatic hydrocarbons such as lower n-paraffins and lower isoparaffins are preferred. The water is preferably pure water, and its electric conductivity is preferably 100 μS / cm or less, more preferably 10 μS / cm or less. The method for producing pure water may be a normal method, and examples include an ion exchange method, a reverse osmosis method, and a distillation method.

The blending amount of the volatile dispersion medium (B) may be an amount sufficient to make the metal particles (A) into a paste, and as a guide, the volume ratio with the metal particles (A) is the amount of the metal particles (A). The volume of the volatile dispersant (B) is from 50 to 200, preferably from 70 to 160 per 100 volumes. In addition, the paste form in this invention contains a cream form. Addition of other metal-based or non-metallic powder, metal compound or metal complex, thixotropic agent, stabilizer, colorant, etc. to the paste-like metal particle composition of the present invention, unless it is contrary to the object of the present invention A small amount or a small amount of the product may be added.

The solidification method of the paste-like metal particle composition of the present invention comprises (A) metal particles having an average particle diameter of greater than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight, and (B) volatility. Metal particles are sintered together by applying ultrasonic vibration having a frequency of 2 kHz or more to a paste-like metal particle composition comprising a dispersion medium while applying pressure. In particular, the solidifying method of the paste-like metal particle composition of the present invention comprises (A) metal particles having an average particle size of more than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight (B ) While applying pressure to a paste-like metal particle composition comprising a volatile dispersion medium and heating at a temperature higher than room temperature and not higher than 400 ° C. and lower than the melting point of the metal particles (A), the frequency is 2 kHz or higher. The volatile dispersion medium (B) is volatilized by applying ultrasonic vibration as described above, and the metal particles (A) are sintered together. As the metal particles (A) for this purpose, metal particles such as gold, silver, copper, aluminum, nickel and tin are suitable. Among these metal particles, aluminum particles have an advantage that they are easily sintered when an ultrasonic vibration having a frequency of 2 kHz or higher is applied while being pressurized even at room temperature.

By applying ultrasonic vibration while applying pressure, particularly by applying ultrasonic vibration while applying pressure and heating, the volatile dispersion medium (B) is volatilized and the metal particles (A) are sintered together. It becomes a solid metal having excellent strength, conductivity and thermal conductivity. At this time, the volatile dispersion medium (B) is volatilized, and then the metal particles (A) may be sintered together, and the metal particles (A) are sintered together with the volatilization of the volatile dispersion medium (B). Alternatively, the metal particles (A) may be sintered together, and then the volatile dispersion medium (B) may be volatilized. Metals such as gold, silver, copper, aluminum, nickel and tin have inherently high strength and extremely high conductivity and thermal conductivity, so the sintered product of the metal particles (A) also has high strength and extremely high conductivity. And has thermal conductivity.

The frequency of the ultrasonic vibration is 2 kHz or more, and preferably 10 kHz or more. The upper limit is not particularly limited, but is about 500 kHz due to the capability of the apparatus. Moreover, since the amplitude of ultrasonic vibration affects sinterability, it is preferably 0.1 to 40 μm, more preferably 0.3 to 20 μm, and still more preferably 0.5 to 12 μm. In addition, it is preferable to directly press the transmitting portion of the ultrasonic vibration to the paste-like metal particle composition so that the ultrasonic vibration is reliably transmitted to the paste-like metal particle composition. Moreover, it is preferable to press the transmitting portion of the ultrasonic vibration through a cover material made of a material that hardly absorbs the ultrasonic vibration. The pressing pressure to the paste-like metal particle composition is preferably 0.9 kPa (0.09 gf / mm ² ) or more, more preferably 9 kPa (0.92 gf / mm ² ) or more, and even more preferably 39 kPa (3.98 gf). / Mm ² ) or more. The upper limit of the pressing pressure is the maximum pressure at which the members to be joined are not destroyed.

The heating temperature may be any temperature that is higher than normal temperature and at which the volatile dispersion medium (B) can be volatilized and the metal particles (A) can be sintered. However, if it exceeds 400 ° C, the volatile dispersion medium (B) may suddenly evaporate and adversely affect the shape of the solid metal. Therefore, it is 400 ° C or less and below the melting point of the metal particles (A). It is necessary that the temperature is 300 ° C. or less. The conductivity of the solid metal formed by sintering the metal particles (A) is preferably 1 × 10 ⁻⁴ Ω · cm or less in terms of volume resistivity, and is 1 × 10 ⁻⁵ Ω · cm or less. More preferably. The thermal conductivity is preferably 5 W / m · K or more, and more preferably 10 W / m · K or more. The shape of the solid metal formed by sintering the metal particles (A) is not particularly limited, and examples thereof include a sheet shape, a film shape, a tape shape, a linear shape, a disk shape, a block shape, a spot shape, and an indefinite shape. The

The metal member joining method of the present invention includes: (A) metal particles having an average particle size of greater than 0.1 μm and not greater than 30 μm and a carbon content of not greater than 2.0% by weight between a plurality of metal members; (B) A paste-like metal particle composition comprising a volatile dispersion medium is interposed, and ultrasonic vibration having a frequency of 2 kHz or more is applied while being pressed to sinter the metal particles (A). To do. In particular, between a plurality of metal members, (A) metal particles having an average particle size of greater than 0.1 μm and 30 μm or less and a carbon content of 2.0% by weight or less, and (B) a volatile dispersion medium, An ultrasonic wave having a frequency of 2 kHz or more while being heated at a temperature higher than normal temperature and not higher than 400 ° C. and lower than the melting point of the metal particles (A) while interposing a paste-like metal particle composition comprising By applying vibration, the volatile dispersion medium (B) is volatilized and the metal particles (A) are sintered together. As the metal particles (A) for this purpose, metal particles such as gold, silver, copper, aluminum, nickel and tin are suitable. Among these metal particles, aluminum particles have an advantage that they are easily sintered by applying ultrasonic vibration having a frequency of 2 kHz or more while being pressurized even at room temperature.

In the method for joining metal members of the present invention, the frequency, amplitude, pressing pressure and heating temperature of ultrasonic vibration are the frequency, amplitude, pressing pressure and ultrasonic vibration frequency in the solidifying method of the paste-like metal particle composition. It is the same as the heating temperature.

When ultrasonic vibration is applied to the paste-like metal particle composition between metal members while applying pressure, in particular, pressurization and heating, the volatile dispersion medium is volatilized and the metal particles are sintered and contacted. Metal plate (for example, gold-plated plate, silver plate, silver-plated plate, copper plate, aluminum plate, nickel-plated metal plate, tin-plated metal plate, etc.); gold-plated substrate, silver substrate, silver-plated substrate, copper substrate, aluminum Metal substrates such as substrates, nickel-plated metal substrates, tin-plated metal substrates; metal parts such as electrodes on electrically insulating substrates; electronic components, electronic devices, electrical components, adhesion strength to metal parts (eg terminals) of electrical devices) It becomes a solid metal having excellent conductivity and thermal conductivity. Therefore, the metal member joining method of the present invention is useful for joining a plurality of metal members, and in particular, an electrode on a metal-based substrate or an electrically insulating substrate, an electronic component, an electronic device, an electrical component, Useful for joining metal parts (eg, terminals) of devices. As such bonding, bonding between metal plates; bonding between a metal plate and a metal part on an electrically insulating substrate; bonding between a chip component such as a capacitor and a resistor and a wiring substrate; semiconductor chip such as a diode, memory, and CPU And bonding between the lead frame or the wiring board; and bonding between the CPU chip having a high heat generation and the cooling plate.

The method for producing a printed wiring board of the present invention comprises: (A) metal particles having an average particle size of greater than 0.1 μm and 30 μm or less, and a carbon content of 2.0% by weight or less; (B) a volatile dispersion medium; The paste-like metal particle composition is applied onto a substrate coated with a curable adhesive, and ultrasonic waves having a frequency of 2 kHz or more are applied to the paste-like metal particle composition while applying pressure to the paste-like metal particle composition. The metal wiring is formed by sintering the adhesive and simultaneously curing the adhesive. In particular, a paste-like metal particle composition comprising (A) metal particles having an average particle size of greater than 0.1 μm and 30 μm or less and a carbon content of 2.0% by weight or less and (B) a volatile dispersion medium. Is applied to a substrate coated with a curable adhesive, and the paste-like metal particle composition is pressurized and heated at a temperature higher than room temperature and not higher than 400 ° C. and lower than the melting point of the metal particles. Forming a metal wiring by applying ultrasonic vibration having a frequency of 2 kHz or more to volatilize the volatile dispersion medium, sinter the metal particles, and simultaneously cure the adhesive. Features. As metal particles for this purpose, metal particles such as gold, silver, copper, aluminum, nickel and tin are suitable. Among these metal particles, aluminum particles have an advantage that they are easily sintered when an ultrasonic vibration having a frequency of 2 kHz or higher is applied while being pressurized even at room temperature.

In the method for manufacturing a printed wiring board of the present invention, the frequency, amplitude, pressing pressure and heating temperature of ultrasonic vibration are the frequency, amplitude, pressing pressure and ultrasonic vibration frequency in the solidifying method of the paste-like metal particle composition. It is the same as the heating temperature.

According to the method for producing a printed wiring board of the present invention, a printed wiring in which a paste-like metal particle composition is applied with a curable adhesive (for example, an epoxy resin adhesive, a silicone resin adhesive, a polyimide resin adhesive). By applying ultrasonic vibration having a frequency of 2 kHz or higher while applying pressure to the paste-like metal particle composition, the metal particles are sintered with each other, resulting in wear resistance and adhesion to the substrate. An excellent metal printed wiring can be formed. The printed wiring board may be a board in which a primer composition is applied on the board and then a curable adhesive is applied. In particular, while applying pressure and applying ultrasonic vibration having a frequency of 2 kHz or more while heating at a temperature higher than normal temperature and not higher than 400 ° C. and lower than the melting point of the metal particles, the volatile dispersion medium can be efficiently obtained. It is possible to produce a printed wiring board having a metal wiring excellent in wear resistance, adhesion to a substrate, conductivity, and thermal conductivity in a short time by volatilization and sintering of metal particles. The method for applying the paste-like metal particle composition onto the substrate is not particularly limited, and includes dispense application, print application, spray application, brush application, injection, and the like. A circuit board can be manufactured by mounting a chip or the like on the printed wiring board by the bonding method described in Paragraph 0031.

Ultrasonic vibration sintered for pasty metal particle composition of the present invention contains a volatile dispersion medium, it is preferably stored in a closed container. When used after long-term storage, it is preferable to use the container after shaking or stirring the container. Refrigerated storage may be performed for the purpose of improving storage stability, and the storage temperature is 10 ° C. or lower. However, when storing in a sealed container, it is preferably a temperature at which the volatile dispersion medium does not solidify.

Incidentally, the ultrasonic vibration sintered for pasty metal particle composition of the present invention, by applying ultrasonic vibration while pressing the metal particles by particularly applying pressure, while heating ultrasonic vibration However, cleaning after sintering is not necessary. However, it may be washed with water or an organic solvent. When the volatile dispersion medium is water or a hydrophilic solvent, it can be washed with water, so there is no problem of VOC generation as in the case of washing with an organic solvent such as alcohol. Each component of the paste-like metal particle composition for ultrasonic vibration sintering in the present invention is easy to clean because it contains few impurities.

Examples and comparative examples of the present invention will be given. In Examples and Comparative Examples, “part” next to a number means “part by weight”. The amount of carbon in the metal particles and the adhesion strength, volume resistivity, and thermal conductivity of the solid metal produced by sintering the metal particles in the paste-like metal particle composition were determined by the following methods. Was measured at 25 ° C. for each test specimen.

[Carbon content]
By heating the metal particles with high frequency in an oxygen stream, the carbon in the organic compound adhering to the metal particles is changed to carbon dioxide, and the amount of carbon dioxide is measured by the infrared absorption spectrum method. Calculated.

[Fixing strength test]
Using a metal mask with a thickness of 150 μm on two 0.8 mm × 1.2 mm land (pad) portions (silver plating finish) provided on a 100 mm × 40 mm glass fiber reinforced epoxy resin substrate with a 1 mm interval. The paste-like metal particle composition was applied (application area: 0.6 mm × 1.0 mm). A 2012 chip capacitor (both ends are silver-plated) was mounted using a chip mounter. Using an ultrasonic thermocompression bonding apparatus, the pressure bonding portion (probe) of the ultrasonic thermocompression bonding apparatus was pressed against the chip capacitor, and was subjected to pressure bonding at a temperature of 200 ° C. for 30 seconds while applying ultrasonic vibration. As a result, the metal particles were sintered, and the land (pad) portion and the 2012 chip capacitor (both ends were silver-plated) were joined. However, when the metal particles were flaky aluminum particles, ultrasonic vibration was applied at room temperature. The side surface of the chip capacitor of the thus obtained bond strength test specimen was pressed at a thickness rate of 23 mm / min with a bond strength tester, and the load when sheared was determined as the bond strength (unit: kgf and N). In addition, the frequency | count of the adhesion strength test was 5 times, and the average value of 5 times was made into the adhesion strength.

[Volume resistivity test]
Using a metal mask having a thickness of 5 mm and an opening having a length of 20 mm and a thickness of 100 μm, the paste-like metal particle composition was printed on an electrically insulating FR-4 glass fiber reinforced epoxy resin substrate. A non-adhesive stainless steel plate having the same size as the epoxy resin substrate and a thickness of 200 μm was stuck to the application part. When pressure was applied for 30 seconds at a temperature of 200 ° C. while applying ultrasonic vibration using an ultrasonic thermocompression bonding apparatus from above the stainless steel plate, the metal particles were sintered to form a film. However, when the metal particles were flaky aluminum particles, ultrasonic vibration was applied at room temperature. With respect to the film-like metal thus obtained, a voltage of 10 volts was applied between 20 mm-long measuring ends to measure resistance, and volume resistivity (unit: Ω · cm) was calculated.

[Thermal conductivity test]
A paste-like metal particle composition is interposed between a 10 mm × 10 mm square silicon wafer 1 and a silicon wafer 2 to a thickness of 40 μm or 80 μm, and ultrasonic vibration is applied using an ultrasonic thermocompression bonding apparatus. Heated at 200 ° C. for 30 seconds. As a result, the metal particles in the paste-like metal particle composition were sintered to form a film. However, when the metal particles were flaky aluminum particles, ultrasonic vibration was applied at room temperature. The film-like metal thus obtained was measured for thermal resistance (unit: ° C./W) at each thickness. The relationship between each thickness (unit: m) and thermal resistance was plotted on a graph, a straight line was drawn, and the slope was calculated as thermal conductivity (unit: W / mK).

[Example 1 to Example 5]
2 parts of 1-hexanol (special grade of reagent sold by Wako Pure Chemical Industries, Ltd.) is added to 20 parts of spherical silver particles (average particle size 0.3 μm, carbon content 0.2% by weight) produced by a commercially available reduction method. A paste-like silver particle composition was prepared by mixing uniformly using a spatula. This paste-like silver particle composition could be applied in a good shape without sagging or flowing during application with a metal mask. This paste-like silver particle composition could be easily discharged from an EFD syringe (manufactured by Sanei Tech Co., Ltd., the inner diameter of the needle attached to the tip is 1.55 mm and the discharge pressure is 50 kPa). In order to obtain each test body of each Example, this paste-like silver particle composition was applied by applying ultrasonic vibration of each ultrasonic vibration application condition (Table 1) for 30 seconds while heating at a temperature of 200 ° C. The silver particles inside were sintered. With respect to this pasty silver particle composition, solid silver strength as a sintered product, volume resistivity, and thermal conductivity were measured, and the measurement results are shown in Table 2. The film-like silver used for volume resistivity measurement had a strength comparable to that obtained by refining. From the above results, this paste-like silver particle composition is useful for producing solid solid silver, useful for joining metal members firmly with good electrical conductivity and thermal conductivity, It can also be seen that it is useful for forming a silver wiring having excellent wear resistance, adhesion to the substrate, electrical conductivity and thermal conductivity.

[Comparative Example 1]
Using the same paste-like silver particle composition as in Examples 1 to 5, an attempt was made to prepare a specimen for fixing strength measurement, a specimen for volume resistivity measurement, and a specimen for thermal conductivity measurement. However, in order to obtain each test body, the ultrasonic vibration of each ultrasonic vibration application condition (Table 3) was applied for 30 seconds while heating at a temperature of 200 ° C. Since the silver particles were not sintered, a specimen could not be prepared. The solid silver fixing strength, volume resistivity, and thermal conductivity could not be measured.

[Example 6]
Instead of the spherical silver particles used in Example 2, flaky silver (average particle diameter 3.0 μm, carbon content 0.7 wt%) obtained by flaking silver particles produced by a commercially available reduction method was used. Prepared a pasty silver particle composition under the same conditions as in Example 2. This paste-like silver particle composition could be applied in a good shape without sagging or flowing during application with a metal mask. This paste-like silver particle composition could be easily discharged from an EFD syringe (manufactured by Sanei Tech Co., Ltd., the inner diameter of the needle attached to the tip is 1.55 mm and the discharge pressure is 50 kPa). In order to obtain each test body of each Example, by applying ultrasonic vibration under the same ultrasonic application conditions as in Example 2 for 30 seconds while heating at a temperature of 200 ° C., in this pasty silver particle composition The silver particles were sintered. The pasty silver particle composition was measured for solid silver solid strength, volume resistivity, and thermal conductivity, and the measurement results are shown in Table 4. The film-like silver used for volume resistivity measurement had a strength comparable to that obtained by refining. From the above results, this paste-like silver particle composition is useful for producing solid solid silver, useful for joining metal members firmly with good electrical conductivity and thermal conductivity, It can also be seen that it is useful for forming a silver wiring having excellent wear resistance, adhesion to the substrate, electrical conductivity and thermal conductivity.

[Comparative Example 2]
Using the same paste-like silver particle composition as in Example 6, an attempt was made to prepare a test specimen for measuring sticking strength, a test specimen for measuring volume resistivity, and a test specimen for measuring thermal conductivity. However, in order to obtain each specimen, ultrasonic vibration under the same ultrasonic vibration application conditions (Table 3) as in Comparative Example 1 was applied for 30 seconds while heating at a temperature of 200 ° C. The silver particles did not sinter and the test specimen could not be produced. Therefore, it was impossible to measure solid silver fixing strength, volume resistivity, and thermal conductivity.

[Comparative Example 3]
Using the same paste-like silver particle composition as in Examples 1 to 5, an attempt was made to prepare a specimen for fixing strength measurement, a specimen for volume resistivity measurement, and a specimen for thermal conductivity measurement. However, in order to obtain each test body, it heated on the same conditions except not applying an ultrasonic vibration. The silver particles did not sinter enough, but were easily broken when touched with a finger, making it impossible to produce a test specimen. Therefore, it was impossible to measure solid silver fixing strength, volume resistivity, and thermal conductivity.

[Example 7]
Lower isoparaffin having a distillation range of 106 ° C to 202 ° C on 20 parts of spherical silver particles (average particle size 0.3 µm, carbon content 0.3 wt%, surface is silver oxide) produced by a commercially available reduction method A paste-like silver particle composition was prepared by adding 1.8 parts (manufactured by Shin Nippon Petrochemical Co., Ltd., trade name ISOZOL 300) and mixing uniformly using a spatula. This paste-like silver particle composition could be applied in a good shape without sagging or flowing during application with a metal mask. This paste-like silver particle composition is slightly unstable due to a change in discharge amount, but is an EFD syringe (manufactured by Sanei Tech Co., Ltd. The inner diameter of the needle attached to the tip is 1.55 mm, and the discharge pressure is 50 kPa. ) Could be discharged continuously. In order to obtain each test body, by applying ultrasonic vibration under the same ultrasonic application conditions as in Example 2 for 30 seconds while heating at a temperature of 200 ° C., the silver particles in the paste-like silver particle composition were removed. Sintered. With respect to this paste-like silver particle composition, solid silver strength as a sintered product, volume resistivity, and thermal conductivity were measured, and the measurement results are summarized in Table 5. The film-like silver used for volume resistivity measurement had a strength comparable to that obtained by refining. From the above results, this paste-like silver particle composition is useful for producing solid solid silver, useful for joining metal members firmly with good electrical conductivity and thermal conductivity, It can also be seen that it is useful for forming a silver wiring having excellent wear resistance, adhesion to the substrate, electrical conductivity and thermal conductivity.

[Comparative Example 4]
Using the same paste-like silver particle composition as in Example 7, an attempt was made to prepare a test specimen for measuring sticking strength, a test specimen for measuring volume resistivity, and a test specimen for measuring thermal conductivity. However, in order to obtain each test body, it heated on the same conditions except not applying an ultrasonic vibration. The silver particles did not sinter enough, the sintered product was brittle, and easily broken when touched with a finger, making it impossible to produce a specimen. Therefore, it was impossible to measure solid silver fixing strength, volume resistivity, and thermal conductivity.

[Example 8]
Example 7 and Example 7 were used except that instead of the spherical silver particles used in Example 7, granular silver particles (average particle size: 2.7 μm, carbon content: 0.7% by weight) produced by a commercially available reduction method were used. A pasty silver particle composition was prepared under the same conditions. This paste-like silver particle composition could be applied in a good shape without sagging or flowing during application with a metal mask. This paste-like silver particle composition is slightly unstable due to a change in discharge amount, but is an EFD syringe (manufactured by Sanei Tech Co., Ltd. The inner diameter of the needle attached to the tip is 1.55 mm, and the discharge pressure is 50 kPa. ) Could be discharged continuously. In order to obtain each test body, by applying ultrasonic vibration under the same ultrasonic application conditions as in Example 2 for 30 seconds while heating at a temperature of 200 ° C., the silver particles in the paste-like silver particle composition were removed. Sintered. With respect to this pasty silver particle composition, solid silver as a sintered product was measured for fixing strength, volume resistivity, and thermal conductivity, and the measurement results are summarized in Table 6. The film-like silver used for volume resistivity measurement had a strength comparable to that obtained by refining. From the above results, this paste-like silver particle composition is useful for producing solid solid silver, useful for joining metal members firmly with good electrical conductivity and thermal conductivity, It can also be seen that it is useful for forming a silver wiring having excellent wear resistance, adhesion to the substrate, electrical conductivity and thermal conductivity.

[Comparative Example 5]
Using the same paste-like silver particle composition as in Example 8, an attempt was made to prepare a test specimen for measuring sticking strength, a test specimen for measuring volume resistivity, and a test specimen for measuring thermal conductivity. However, in order to obtain each test body, it heated on the same conditions except not applying an ultrasonic vibration. The silver particles did not sinter enough, the sintered product was brittle, and easily broken when touched with a finger, making it impossible to produce a specimen. Therefore, it was impossible to measure solid silver fixing strength, volume resistivity, and thermal conductivity.

[Example 9]
Reduction powder of spherical copper particles produced by a commercially available atomizing method (copper particles having an average particle diameter of 4 μm and a carbon content of 0.01% by weight or less are immersed in an ascorbic acid aqueous solution having a concentration of 15% by weight. Add 1.5 parts of 1-hexanol (special grade grade of Wako Pure Chemical Industries, Ltd.) to 20 parts of copper oxide on the surface of the particles, and then mix evenly using a spatula. Thus, a paste-like copper particle composition was prepared.
This paste-like copper particle composition could be applied in a good shape without sagging or flowing during application with a metal mask. This paste-like copper particle composition could be easily discharged from an EFD syringe (manufactured by Sanei Tech Co., Ltd., the inner diameter of the needle attached to the tip is 1.55 mm and the discharge pressure is 50 kPa). In order to obtain each test body, the copper particles in this paste-like copper particle composition were applied by applying ultrasonic vibration under the same ultrasonic application conditions as in Example 2 while heating at a temperature of 200 ° C. Sintered. About this paste-form copper particle composition, the fixed strength, volume resistivity, and thermal conductivity of solid copper which is a sintered product were measured, and the measurement results are shown in Table 7. The film-like copper used for volume resistivity measurement had a strength comparable to copper obtained by a refining method. From the above results, this paste-like copper particle composition is useful for producing strong solid copper, useful for strongly joining metal members with good electrical and thermal conductivity, It can also be seen that it is useful for forming copper wiring having excellent wear resistance, adhesion to the substrate, electrical conductivity, and thermal conductivity.

[Comparative Example 6]
Using the same paste-like copper particle composition as that of Example 9, an attempt was made to prepare a test specimen for measuring sticking strength, a test specimen for measuring volume resistivity, and a test specimen for measuring thermal conductivity. However, in order to obtain each test body, it heated on the same conditions except not applying an ultrasonic vibration. The copper particles did not sinter sufficiently, the sintered product was brittle, and easily broken when touched with a finger, making it impossible to produce a test specimen. Therefore, it was impossible to measure solid copper fixation strength, volume resistivity, and thermal conductivity.

[Example 10]
To 20 parts of commercially available spherical gold particles (average particle size of 1 μm, carbon content of 0.1% by weight or less), 1.0 part of 1-hexanol (special grade of reagent sold by Wako Pure Chemical Industries, Ltd.) is added, and a spatula is used. A paste-like gold particle composition was prepared by mixing uniformly. This paste-like gold particle composition could be applied in a good shape without sagging or flowing during application with a metal mask. This paste-like gold particle composition could be easily discharged from an EFD syringe (manufactured by Sanei Tech Co., Ltd., the inner diameter of the needle attached to the tip is 1.55 mm and the discharge pressure is 50 kPa). In order to obtain each specimen, by applying ultrasonic vibration under the same ultrasonic application conditions as in Example 2 for 30 seconds while heating at a temperature of 200 ° C., the gold particles in the paste-like gold particle composition were Sintered. With respect to this paste-like gold particle composition, the fixing strength, volume resistivity, and thermal conductivity of solid gold as a sintered product were measured, and the measurement results are shown in Table 8. The film-like gold used for measuring the volume resistivity had a strength comparable to that obtained by the refining method. From the above results, this paste-like gold particle composition is useful for producing strong solid gold, useful for joining metal members firmly with good electrical conductivity and thermal conductivity, In addition, it can be seen that it is useful for forming a gold wiring having excellent wear resistance, adhesion to a substrate, electrical conductivity, and thermal conductivity.

[Comparative Example 7]
Using the same paste-like gold particle composition as in Example 10, an attempt was made to prepare a test specimen for measuring sticking strength, a test specimen for measuring volume resistivity, and a test specimen for measuring thermal conductivity. However, in order to obtain each test body, it heated on the same conditions except not applying an ultrasonic vibration. The gold particles did not sinter sufficiently, the sintered product was brittle, and easily broken when touched with a finger, making it impossible to produce a specimen. Therefore, the solid gold fixing strength, volume resistivity, and thermal conductivity were not measurable.

[Example 11]
Add 6 parts of isopropanol (special grade reagent sold by Wako Pure Chemical Industries, Ltd.) to 20 parts of commercially available flaky aluminum particles (average particle size 20 μm, carbon content 0.1 wt% or less) and mix evenly using a spatula By doing so, a paste-like aluminum particle composition was prepared. This paste-like aluminum particle composition was able to be applied in a measurable shape, although slight sagging, flow, etc. were observed in application with a metal mask. The aluminum particles in this paste-like aluminum particle composition were sintered by applying ultrasonic vibration under the ultrasonic wave application conditions shown in Table 9 for 60 seconds at room temperature using an ultrasonic thermocompression bonding apparatus. With respect to this pasty aluminum particle composition, the fixing strength, volume resistivity, and thermal conductivity of solid aluminum as a sintered product were measured, and the measurement results are shown in Table 10. The film-like aluminum used for measuring the volume resistivity had a strength comparable to that obtained by refining. From the above results, this paste-like aluminum particle composition is useful for producing strong solid aluminum, useful for joining metal members firmly with good electrical and thermal conductivity, It can also be seen that it is useful for forming an aluminum wiring having excellent wear resistance, adhesion to a substrate, electrical conductivity and thermal conductivity.

[Comparative Example 8]
Using the same paste-like aluminum particle composition as in Example 11, an attempt was made to prepare a test specimen for measuring sticking strength, a test specimen for measuring volume resistivity, and a test specimen for measuring thermal conductivity. However, in order to obtain each test body, it heated on the same conditions except not applying an ultrasonic vibration. The aluminum particles did not sinter sufficiently, the sintered product was brittle, and easily broken when touched with a finger, making it impossible to produce a test specimen. For this reason, the fixing strength, volume resistivity, and thermal conductivity of solid aluminum cannot be measured.

Ultrasonic vibration sintered for pasty metal particle composition of the present invention, a method of solidifying the pasty metal particle composition, method of joining the metal member is formed of conductive traces on the printed circuit board; resistor Ya Formation of electrodes for various electronic components such as capacitors and various display elements; formation of conductive films for electromagnetic wave shielding; bonding between metal plates; bonding between metal plates and metal parts on an electrically insulating substrate; capacitors, resistors, diodes Bonding chip components such as memory and arithmetic elements (CPU) to substrates; forming solar cell electrodes; forming external electrodes for chip-type ceramic electronic components such as multilayer ceramic capacitors, multilayer ceramic inductors and multilayer ceramic actuators Useful. The method for producing a printed wiring board of the present invention is useful for producing a printed wiring board having metal wiring.

Claims (17)

To a paste-like metal particle composition comprising (A) a metal particle having an average particle size greater than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight and (B) a volatile dispersion medium, A method for solidifying a paste-like metal particle composition, wherein the metal particles are sintered by applying ultrasonic vibration having a frequency of 2 kHz or higher while pressing. While pressing, and no more than 400 ° C. higher than the ambient temperature with heating at a temperature lower than the melting point of the metal particles, characterized in that the frequency applying ultrasonic vibration is more than 2 kHz, according to claim 1, wherein A method for solidifying a paste-like metal particle composition. Wherein the amplitude of the ultrasonic vibration is 0.1 to 40, solidification method according to claim 1 or claim 2 pasty metal particle composition. Pressurization and wherein the at 0.9kPa (0.09gf / mm ²⁾ or more, solidifying method of claim 1 or claim 2 pasty metal particle composition. The method for solidifying a paste-like metal particle composition according to claim 3 , wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more. Between a plurality of metal members, a paste comprising (A) metal particles having an average particle size greater than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight, and (B) a volatile dispersion medium. A method for joining metal members, comprising interposing a metallic metal composition and applying ultrasonic vibration having a frequency of 2 kHz or more while applying pressure to sinter the metal particles. While pressing, and no more than 400 ° C. higher than the ambient temperature with heating at a temperature lower than the melting point of the metal particles, characterized in that the frequency applying ultrasonic vibration is more than 2 kHz, according to claim 6, wherein A method for joining metal members. The metal member joining method according to claim 6 , wherein the metal member is a metal member of an electronic component or an electrical component. The metal member joining method according to claim 7 , wherein the metal member is a metal member of an electronic component or an electric component. The method for joining metal members according to any one of claims 6 to 9 , wherein the amplitude of the ultrasonic vibration is 0.1 to 40 µm. The method for joining metal members according to any one of claims 6 to 9 , wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more. The method for joining metal members according to claim 10 , wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more. A paste-like metal particle composition comprising (A) a metal particle having an average particle size greater than 0.1 μm and not more than 30 μm and a carbon content of not more than 2.0% by weight and (B) a volatile dispersion medium is curable. It is applied onto a substrate coated with an adhesive, and the metal particles are sintered by applying ultrasonic vibration having a frequency of 2 kHz or higher while applying pressure to the paste-like metal particle composition. A method for producing a printed wiring board, comprising forming a metal wiring by curing. While pressing, and while heating at a temperature below the melting point of at most 400 ° C. higher than the normal temperature the metal particles, characterized in that the frequency applying ultrasonic vibration is more than 2 kHz, according to claim 13, wherein Manufacturing method of printed wiring board. The method for producing a printed wiring board according to claim 13 or 14 , wherein the amplitude of the ultrasonic vibration is 0.1 to 40 µm. The method for producing a printed wiring board according to claim 13 or 14, wherein the pressure is 0.9 kPa (0.09 gf / mm ² ) or more. The method for producing a printed wiring board according to claim 15 , wherein the pressurization is 0.9 kPa (0.09 gf / mm ² ) or more.

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