JP4875871B2 - Method for attaching solder powder to electronic circuit board and electronic wiring board with solder - Google Patents

Description

  The present invention provides a method for finely attaching a solder powder only to an exposed fine metal surface of an electronic circuit board (including a printed wiring board), and melting the solder powder in order to attach an electronic component to the electronic circuit board. The present invention relates to a method for forming a thin solder layer on an exposed metal surface and an electronic circuit board on which this solder precoat is formed.

  In recent years, an electronic circuit board having an electronic circuit pattern formed on an insulating substrate such as an electronic circuit board, for example, a plastic substrate (also with a film), a ceramic substrate, or a metal substrate coated with plastic has been developed. On top of this, means for forming an electronic circuit by soldering electronic components such as an IC element, a semiconductor chip, a resistor, and a capacitor are widely adopted.

  In this case, in order to join the lead terminal of the electronic component to a predetermined portion of the circuit pattern, a solder precoat is previously formed on the surface of the conductive circuit electrode (metal) exposed on the electronic circuit board, In general, after solder paste or flux is printed and a predetermined electronic component is positioned and mounted, solder precoat or solder precoat and solder paste are reflowed and soldered.

  Recently, in order to reduce the size of electronic products, electronic circuits are required to have fine pitches. Fine pitch components within a small area, for example, 0.3 mm pitch QFP (Quad Flat Package) type LSI, CSP (Chip Size). Package), 0.15 mm pitch FC (Flip Chip) and the like are often mounted. For this reason, a fine solder circuit pattern corresponding to the fine pitch is required for the electronic circuit board.

  In order to form a solder precoat on an electronic circuit board, a plating method, a HAL (hot air leveler) method, a method of printing a solder powder paste, and reflowing is performed. However, it is difficult for the solder circuit manufacturing method by the plating method to make the solder layer to a required thickness, and the HAL method and the solder paste printing method are difficult to cope with the fine pitch pattern.

  Therefore, as a method for forming a solder precoat on an electronic circuit board without the need for troublesome operations such as alignment of circuit patterns, it is possible to react with a tackifier compound on the surface of a conductive circuit electrode of an electronic circuit board. A method is disclosed in which solder powder is applied to the adhesive portion, and then the electronic circuit board is heated to melt the solder to form a solder precoat (see, for example, Patent Document 1).

  According to the method disclosed in Patent Document 1, it is possible to form a solder precoat on a fine electronic circuit pattern with a simple operation and provide a highly reliable circuit electronic circuit board. Since the solder powder is attached to the circuit electronic circuit board, it is inevitable that the powder adheres to an extra part other than the part where the powder is necessary due to static electricity or the like, and it also attaches to the exposed metal surface of the electronic circuit board. In some cases, antistatic measures are necessary. Solder adhesion by the dry method causes powder scattering, etc., which hinders finer circuit electronic circuit boards, and the excessively adhered solder powder is difficult to recover during dry processing and is an efficient solder powder. It was an obstacle to use. Such a problem becomes remarkable particularly when a fine solder powder is used.

Japanese Patent Laid-Open No. 7-7244

  In the present invention, the exposed metal surface (conductive circuit electrode surface) on the electronic circuit board is subjected to a tackifying compound treatment to impart adhesiveness to the metal surface, and solder powder is attached to the adhesive part. Next, in the method of manufacturing an electronic circuit board in which the electronic circuit board is heated and the solder is dissolved to form a solder precoat, a method of strongly adhering the solder powder to the adhesive part after taking an electrostatic measure, and adhesion of the solder powder A method for increasing the amount of solder, a method for adhering solder powder capable of realizing a finer circuit pattern, a method for reusing solder powder with little deterioration in the adhesion of solder powder, and a method for correcting the adhesion of solder powder to electronic circuit boards with insufficient solder adhesion The purpose is to provide.

The inventor of the present invention has reached the present invention as a result of diligent efforts to solve the above problems. That is, the present invention
[1] The exposed metal surface of the electronic circuit board is selected from naphthotriazole derivatives, benzotriazole derivatives, imidazole derivatives, benzoimidazole derivatives, mercaptobenzothioazole derivatives and benzothiazole thio fatty acids. the tackiness imparted by treatment with tackifying compound, a solder powder slurry suspension in liquid viscosity attaching portion supplies perpendicularly to the electronic circuit board from the supply container of the solder powder slurry to vibrate, A method for adhering solder powder comprising adhering solder powder.
[2] The solder powder adhering method according to the above [1], wherein the solder powder slurry supply container has a dropper shape.

[3] The solder powder adhering method according to the above [1] or [2], wherein the liquid used for the solder powder slurry is deoxygenated water or water to which a rust inhibitor is added.
[4] [1] After attaching the solder powder by deposition method of the solder powder according to any one of to [3], the electronic circuit board is immersed in a liquid, removing the solder powder excessively adheres A method for adhering solder powder, characterized in that:
[5] The solder powder adhering method according to the above [4], wherein the liquid used for removing the solder powder is deoxygenated water or water to which a rust inhibitor is added.
[6] The solder powder according to [4] or [5] described above, wherein, when removing the excessively adhered solder powder, vibration is applied to the electronic circuit board or the immersion liquid to remove the excessively adhered solder powder. Adhesion method.

[7] The solder powder adhering method according to [6], wherein the vibration in removing the excessively adhered solder powder is a liquid that imparts ultrasonic vibration to the electronic circuit board or is subjected to ultrasonic vibration.

[8] Collect the solder powder removed by the solder powder adhering method according to any one of [4] to [7] in a slurry state and supply the solder powder to the adhesive portion of the electronic circuit board in a slurry state again. A method for adhering solder powder comprising:
[9] The method of attaching the solder powder according to either Re not have the above-mentioned [1] to [8], the exposed metal surface of the electronic circuit board, after attaching the solder powder, a circuit by heating and melting A method of manufacturing a soldered electronic circuit board comprising forming.

[10] The deposition method of the solder powder according to either Re not have the above-mentioned [1] to [8], the exposed metal surface of the electronic circuit board, the solder non-electronic circuit substrate formed by adhering the solder powder When there is an adhering part, supplying a solder powder slurry to the part and adhering the solder powder, a solder powder adhering method,
By solving this problem, the above problems were solved.

  Forming and collecting a fine solder circuit pattern with high solder powder adhesion strength and no trouble caused by static electricity with a simple operation by the solder powder adhesion method and the electronic circuit board manufacturing method using the same according to the present invention Solder powder can be reused. In particular, even in a fine circuit pattern, an effect of reducing a short circuit due to solder metal between adjacent circuit patterns is obtained, and the reliability of the electronic circuit board is remarkably improved. In addition, the electronic circuit board manufacturing method of the present invention can realize miniaturization and high reliability of a circuit board on which electronic components are mounted, and can provide an electronic device having excellent characteristics.

  Electronic circuit boards subject to the present invention include plastic substrates, plastic film substrates, glass cloth substrates, paper substrates, epoxy resin substrates, wafers, substrates in which metal plates are laminated on ceramic substrates, or plastics or ceramics on metal substrates. A single-sided electronic circuit board, a double-sided electronic circuit board, a multilayer electronic circuit board, a flexible electronic circuit board, or the like in which a circuit pattern is formed using a conductive material such as metal on an insulating substrate coated with metal.

  The present invention, for example, treats the surface of the conductive circuit electrode on the electronic circuit board with a tackifier compound to impart tackiness to the electrode surface, and adheres solder powder to the tacky portion, thereby causing troubles such as static electricity. Can be avoided completely, the solder powder can be adhered to the adhesive part with high adhesion strength, and can be adhered faithfully to a fine pattern. This is a method for manufacturing a soldered electronic circuit board in which the solder powder adhering to the substrate is removed, and then the electronic circuit board is heated to melt the adhering solder to form a solder circuit.

  As the exposed conductive material forming the circuit, copper is used in most cases, but the present invention is not limited to this, and a conductive metal whose surface can be obtained with a tackifier that will be described later. If it is. Examples of these substances include metals including Ni, Sn, Ni—Au, solder alloys, and the like.

  The tackifier compound preferably used in the present invention includes naphthotriazole derivatives, benzotriazole derivatives, imidazole derivatives, benzoimidazole derivatives, mercaptobenzozothiazole derivatives described in Patent Document 1. And benzothiazole thio fatty acid. These tackifying compounds have a particularly strong effect on copper, but can also provide tackiness to other conductive substances.

  In the present invention, when tackiness is imparted to the surface of the conductive circuit electrode on the electronic circuit board, at least one of the above tackifying compounds is dissolved in water or acidic water, and preferably has a pH of about 3 to 4. Adjust to acidity and use. Examples of the substance used for adjusting the pH include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid because the conductive circuit electrode is a metal. As the organic acid, formic acid, acetic acid, propionic acid, malic acid, oxalic acid, malonic acid, succinic acid, tartaric acid and the like can be used. The concentration of the tackifier compound is not strictly limited, but is appropriately adjusted according to solubility and use conditions, but preferably a concentration in the range of 0.05% by mass to 20% by mass is easy to use as a whole. . If the concentration is lower than this, the formation of an adhesive film becomes insufficient, which is not preferable in terms of performance.

  The treatment temperature and the production amount of the adhesive film are better when the treatment temperature is slightly warmer than room temperature. Although it varies depending on the tackifying compound concentration, the type of metal, and the like, it is generally in the range of about 30 ° C to 60 ° C. The treatment time is not limited, but it is preferable to adjust other conditions such as pH, tackifying compound concentration, treatment temperature and the like so as to be in the range of about 5 seconds to 5 minutes from the work efficiency.

  In this case, it is preferable to coexist 100 to 1000 ppm with copper (monovalent or divalent) as ions in the solution because the production efficiency such as the production rate and production amount of the adhesive film is increased.

The electronic circuit board to be processed covers the conductive circuit electrode part other than the surface part of the conductive circuit electrode to be soldered on the electronic circuit board with a resist or the like, and the conductive circuit electrode part of the circuit pattern (on the substrate, It is preferable that only the exposed metal surface) be exposed and treated with a tackifying compound solution.
Here, if an electronic circuit board coated with a resist or the like is immersed in the above-mentioned tackifier compound solution, or the solution is applied to or sprayed on the electronic circuit board, the surface of the conductive circuit electrode is given tackiness. Is done.

Examples of the metal composition of the solder powder used in the method for producing an electronic circuit board of the present invention include Sn—Pb, Sn—Pb—Ag, Sn—Pb—Bi, Sn—Pb—Bi—Ag, and Sn. -Pb-Cd system is mentioned. Further, from the viewpoint of eliminating Pb in recent industrial waste, Sn-In, Sn-Bi, In-Ag, In-Bi, Sn-Zn, Sn-Ag, Sn-Cu, which does not contain Pb. -Based, Sn-Sb-based, Sn-Au-based, Sn-Bi-Ag-Cu-based, Sn-Ge-based, Sn-Bi-Cu-based, Sn-Cu-Sb-Ag-based, Sn-Ag-Zn-based, Sn -Cu-Ag system, Sn-Bi-Sb system, Sn-Bi-Sb-Zn system, Sn-Bi-Cu-Zn system,
Sn-Ag-Sb, Sn-Ag-Sb-Zn, Sn-Ag-Cu-Zn, and Sn-Zn-Bi are particularly preferable.

  When the electronic circuit board of the present invention is produced using an alloy composition selected from Pb-free solder, particularly preferably Sn and Zn, or solder containing Sn and Zn and Bi among the above solder powders, Sn-Pb Since the reflow temperature is lowered to the same level as the solder of the system, the life of the mounted parts can be extended, and it is possible to cope with the diversification of parts.

  As the particle size of the solder powder, standards such as 53 to 22 μm, 45 to 22 μm, and 38 to 22 μm are defined in the Japanese Industrial Standard (JIS) by sieving. In order to measure the average particle size of the solder powder of the present invention, a method using a standard sieve and a balance defined by JIS can be usually used. In addition, image analysis using a microscope or Coulter counter using an electrozone method can also be performed. The principle of the Coulter Counter is shown in the “Powder Engineering Handbook” (Edition of Powder Engineering, 2nd edition, p19-p20), but the solution in which the powder is dispersed is passed through the pores in the partition walls. The particle size distribution of the powder is measured by measuring the change in electrical resistance on both sides of the pore, and the number ratio of the powder diameter can be measured with good reproducibility. The average particle size of the solder powder of the present invention can be determined using the method described above.

In the present invention, the adhesion of the solder powder to the electronic circuit board to which the tackiness has been imparted is avoided by supplying the solder powder slurry suspended in the liquid to the tackiness imparting surface of the electronic circuit board in order to avoid troubles due to static electricity. Solder powder is adhered. In this case, the supply direction of the solder powder slurry to the tackiness imparting surface of the electronic circuit board is not limited.
However, in order to increase the adhesion thickness of the solder powder and to increase the adhesion strength, it is preferable to supply the solder powder approximately perpendicularly to the tackiness imparting surface of the electronic circuit board. For example, FIG. 1 schematically shows the method of attaching solder powder of the present invention. That is, this can be achieved by making the tackiness imparting surface 4 of the electronic circuit board 3 face upward and supplying the solder powder slurry 2 from above. This is presumed to be because the solder powder is supplied vertically to the adhesive part and strongly contacts the adhesive part. Of course, even if a slurry of solder powder is supplied in parallel to the tackiness imparting surface of the electronic circuit board, the necessary amount of solder powder can adhere to the adhesive portion.

  The concentration of the slurry of the solder powder is preferably as high as possible within the range in which the solder powder can flow, but the solder powder is liable to settle, and in order to avoid clogging, the limit concentration (critical concentration) at which the solder powder can flow is set. 80% or less, preferably about 30-50% is used. The critical concentration varies greatly depending on the shape and size of the solder particles, the flow rate of the slurry, the viscosity of the liquid, the application of vibrations, etc., so it can be easily tested, so check the critical concentration in the operating conditions in advance or check the clogging conditions It is necessary to keep it.

The electronic circuit board to which the solder powder is adhered is then removed in the liquid to remove the excess solder powder, so that the solder powder adheres to the non-adhesive part due to static electricity during the removal operation, or the solder powder becomes static due to static electricity. Aggregation is prevented, and a fine-pitch circuit board or fine solder powder can be used.
When the solder powder adhesion process is performed in a dry process, an electronic circuit board, such as a plastic substrate, that is easily charged with static electricity can be electrostatically removed by brushing the surface of the plastic with a brush to remove excess solder powder after the solder powder adheres. If the solder powder is fine, it easily adheres to a portion that does not impart tackiness, and the solder powder adheres to a portion that is not necessary, and a short circuit is likely to occur between circuit patterns. In the present invention, this problem is solved by removing the excess solder powder in the liquid, thereby causing troubles due to static electricity.

In the present invention, water or a mixed solvent of water and a water-soluble low-boiling organic solvent can be used as the liquid used for the solder powder slurry in order to prevent troubles due to static electricity. In view of problems such as environmental pollution, water is preferred. In this case, in order to prevent the solder powder from being oxidized by dissolved oxygen in the liquid, deoxygenated water or water added with a rust inhibitor is preferable.
In particular, when considering the recycling use of solder powder, deoxidized water and / or water to which a rust inhibitor is added is preferable in order to prevent the solder powder from being oxidized by dissolved oxygen in the liquid. As deoxygenated water, water degassed by heating, or water bubbled with an inert gas such as carbon dioxide, nitrogen or argon can be used. Moreover, the water which added the rust preventive agent to the water which added the rust preventive agent, or water may be sufficient. When such deoxygenated water and / or water added with a rust inhibitor is used, oxidation of the removed solder powder surface is prevented, which is convenient for recovery and reuse. When a rust preventive agent is used, it may be necessary to wash with water later, so that the use of mere deoxygenated water is particularly preferable.

  In the present invention, excess solder powder can be removed by immersing or spraying the electronic circuit board in a liquid. The removal of excess solder powder may be performed by gently brushing the surface of the electronic circuit board with a brush or the like in the liquid. However, the electronic circuit board or the solder removal liquid is vibrated, preferably 0.1 Hz to several hundred Hz or several hundred kHz to It is preferable to carry out by applying vibration of several thousand kHz. When removing the solder powder in the liquid, the solder powder removed in the solder removal liquid easily settles and can be easily recovered without scattering.

In order to prevent oxidation of the solder powder used in the present invention, it is also preferable to coat the surface of the solder powder. Solder powder coating agents include benzothiazole derivatives, amines having 4 to 10 carbon atoms in the side chain, thiourea, silane coupling agents, lead, tin, gold, inorganic acid salts and organic acid salts. It is preferable to use at least one of them, and as the organic acid salt, it is preferable to use at least one selected from lauric acid, myristic acid, palmitic acid and stearic acid.
The processing method of the present invention can be effectively used not only for the solder precoat circuit board described above but also for bump formation for BGACSP, FC bonding, etc., and these are naturally included in the electronic circuit board of the present invention. is there.

  The electronic circuit board with the excess solder powder removed and the solder powder adhered to the adhesive portion is then dried, and then the adhered solder powder is heated and melted in a reflow process to obtain a soldered electronic circuit board. In this heating, the solder powder adhering to the adhesive portion only needs to be melted, so that the processing temperature, processing time, etc. can be easily determined in consideration of the melting point of the solder powder.

The excess solder powder removed from the electronic circuit board in the liquid can be easily separated from the solder removal liquid, so that it can be collected and recovered and used as it is as the solder powder slurry in the solder powder adhesion process without drying.
The solder powder slurry is not only used for a normal solder powder adhesion process by a supply means such as extrusion by a pump and flowing the solder powder from the bottom to overflow, but also a small dropper-like supply means as a supply means. Use is also possible.

  For example, when solder processing is performed on a normal electronic circuit board and there is a solder non-adhered part, the solder non-adhered part is treated with a tackifying compound to impart tackiness to the dropper-like supply means. Supply solder powder slurry, or treat with a tackifying compound to give tackiness, and when solder powder is attached to this, there are solder unattached parts, solder with a small dropper-like supply means It can also be used for solder circuit repair and correction methods such as supplying powder slurry.

  The soldered electronic circuit board produced by the present invention can be suitably used for a mounting method of an electronic component including a step of placing the electronic component and a step of reflowing the solder to join the electronic component. For example, after the solder precoat is formed on the electrodes of the electronic circuit board according to the present invention, the solder paste is applied by a printing method or the like, and the electronic components (chip components, CSP, etc.) are placed on the solder paste and are collectively collected by a reflow heat source. Solder together. As the reflow heat source, a hot air furnace, an infrared furnace, a vapor condensation soldering device, a light beam soldering device, or the like can be used.

For fine-pitch electrodes where solder paste cannot be printed, adhesive flux is printed on the solder-precoated electrode and electronic components (semiconductor chips, etc.) are placed, or adhesive flux is applied to the bumps of electronic components. The electronic component can be bonded to the circuit board by reflowing after being mounted on the solder precoated electrode.
Furthermore, Au bumps (stud bumps, etc.) are formed on the electrodes of the semiconductor chip, and this is bonded to the solder precoat formed on the electrodes of the circuit board by pressure heating, or a non-conductive resin is applied to the circuit board. A semiconductor chip mounting method such as a method in which a semiconductor chip having an Au bump formed on an electrode is pressed and heated and thermocompression-bonded is supplied.

  The reflow process of the present invention differs depending on the solder alloy composition. For example, in the case of Sn—Zn systems such as 91Sn / 9Zn, 89Sn / 8Zn / 3Bi, 86Sn / 8Zn / 6Bi, etc., it is performed in two steps of preheating and reflow. Preferably, each condition is that the preheat is 130 to 180 ° C., preferably 130 to 150 ° C., the preheat time is 60 to 120 seconds, preferably 60 to 90 seconds, and the reflow is 210 to 230 ° C., preferably 210-220 degreeC and reflow time are 30-60 seconds, Preferably, it is 30-40 seconds. The reflow temperature in other alloy systems is +20 to + 50 ° C. with respect to the melting point of the alloy used, preferably +20 to + 30 ° C. with respect to the melting point of the alloy, and the other preheating temperature, preheating time and reflow time are the same as above. Any range is acceptable.

  The above reflow process can be carried out in nitrogen or air. In the case of nitrogen reflow, by setting the oxygen concentration to 5 apparent volume% or less, preferably 0.5 apparent volume% or less, the wettability of the solder to the solder circuit is improved compared to the case of atmospheric reflow, and solder balls are also generated. Less and stable processing is possible.

の２質量％水溶液を、酢酸によりｐＨを約４に調整して用いた。該水溶液を４０℃に加温し、これに塩酸水溶液により前処理した前記プリント配線板を３分間浸漬し、銅回路表面に粘着性物質を生成させた。 Example 1
A printed wiring board having a minimum electrode interval of 50 μm was produced. Copper was used for the conductive circuit.
As tackifying compound solution, an imidazole compound represented by the following general formula (1)

A 2 mass% aqueous solution of was used after adjusting the pH to about 4 with acetic acid. The aqueous solution was heated to 40 ° C., and the printed wiring board pretreated with an aqueous hydrochloric acid solution was immersed in the solution for 3 minutes to generate an adhesive substance on the surface of the copper circuit.

Next, a slurry in which 96.5Sn / 3.5Ag solder powder having an average particle diameter of about 20 μm is dispersed in deoxygenated water at a concentration of 50% by volume is supplied onto the substrate, and vibration of 50 Hz is applied to the printed wiring board. Solder powder was attached. Next, after gently rocking in deoxygenated water, the solder powder-attached printed wiring board was dried.
Flux was supplied to the printed wiring board by spraying and placed in an oven at 240 ° C. to melt the solder powder, and a 96.5 Sn / 3.5 Ag solder precoat having a thickness of about 20 μm was formed on the exposed copper circuit. The average particle size of the solder powder was measured using a microtrack. No bridge or the like occurred in the solder circuit.

(Example 2)
An area array printed wiring board having an electrode diameter of 70 μm and an interval of 60 μm was produced. Copper was used for the conductive circuit.

  As a tackifying compound solution, a 2% by mass aqueous solution of the same imidazole compound as in Example 1 was used after adjusting the pH to about 4 with acetic acid. The aqueous solution was heated to 40 ° C., and the printed wiring board pretreated with an aqueous hydrochloric acid solution was immersed in the solution for 3 minutes to generate an adhesive substance on the surface of the copper circuit.

Next, the printed wiring board was dispersed in deoxygenated water at a concentration of 50% by volume of 96.5Sn / 3.5Ag solder powder having an average particle size of about 60 μm, and the slurry was supplied onto the substrate to give a vibration of 50 Hz. After lightly rocking in deoxygenated water, the printed wiring board was dried.
This printed wiring board flux was supplied by spraying and placed in an oven at 240 ° C. to melt the solder powder.
A 96.5 Sn / 3.5 Ag solder bump having a thickness of about 40 μm was formed on the exposed portion of the copper circuit.
Good bumps were formed on the solder circuit, and no bridges or unbumped parts were generated.

Adhesiveness is imparted to the exposed metal part on the substrate, and solder powder is adhered to the adhesive part. Then, excess solder powder in the liquid is removed, the removed electronic circuit board is heated, and the solder powder is removed. The method of manufacturing a soldered electronic circuit board that has a solder precoat on the electrodes on the electronic circuit board after melting has the effect of reducing the short circuit due to the solder metal between adjacent circuit patterns even in a fine circuit pattern. A soldered electronic circuit board with significantly improved performance could be manufactured.
As a result, it is possible to reduce the size and reliability of a circuit board having a fine circuit pattern and mounted with highly reliable electronic components, and to achieve electronic circuit boards, electronic components that can achieve high reliability and high mounting density. It becomes possible to provide a mounted circuit board and an electronic device with excellent characteristics, and can be applied to electronic device manufacturing.
The removed excess solder powder can be collected and recycled for use in the solder powder adhesion process, so that the usage rate of the solder powder can be increased.

It is the figure which showed typically the adhesion method of the solder powder of this invention.

Explanation of symbols

1 Slurry supply container 2 Solder powder slurry
3 Electronic circuit board 4 Adhesive surface

Claims (10)

Adhesiveness selected from naphthotriazole derivatives, benzotriazole derivatives, imidazole derivatives, benzoimidazole derivatives, mercaptobenzobenzothiazole derivatives and benzothiazole thio fatty acids on the exposed metal surface of the electronic circuit board the tackiness was imparted by treatment with imparting compound, a solder powder slurry suspension in liquid viscosity attaching portion supplies perpendicularly to the electronic circuit board from the supply container of the solder powder slurry to vibrate, the solder powder A method for adhering solder powder comprising adhering.   The solder powder adhering method according to claim 1, wherein the solder powder slurry supply container has a dropper shape.   The method for adhering solder powder according to claim 1 or 2, wherein the liquid used in the solder powder slurry is deoxygenated water or water to which a rust inhibitor is added. After depositing the solder powder by deposition method of the solder powder according to claim 1, the electronic circuit board is immersed in the liquid, and removing the solder powder excessively adheres Solder powder adhesion method.   The method for adhering solder powder according to claim 4, wherein the liquid used for removing the solder powder is deoxygenated water or water to which a rust inhibitor is added.   6. The method for adhering solder powder according to claim 4 or 5, wherein, when the excessively adhered solder powder is removed, the excessively adhered solder powder is removed by applying vibration to the electronic circuit board or the liquid to be immersed. The solder powder adhesion method according to claim 6, wherein the vibration in removing the excessively adhered solder powder is a liquid that imparts ultrasonic vibration or ultrasonic vibration to the electronic circuit board.   The solder powder removed by collecting the solder powder removed by the solder powder adhering method according to claim 4 in a slurry state and supplying the solder powder to the adhesive portion of the electronic circuit board again in a slurry state. Method. The method of attaching the solder powder according to either Re not have the claims 1 to 8, the exposed metal surface of the electronic circuit board, after attaching the solder powder consists of heating and melting to form a circuit solder A method for manufacturing an attached electronic circuit board. The method of attaching the solder powder according to either Re not have the claims 1 to 8, the exposed metal surface of the electronic circuit board, when a solder unattached portion to an electronic circuit board which is formed by attaching the solder powder A method for attaching solder powder, comprising supplying a solder powder slurry to the portion and attaching the solder powder.

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