JP2005244005A - Method for manufacturing circuit board and circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit board having a through hole/via hole capable of surely connecting wiring films to each other in a less state of defects and to provide a method for simply forming the circuit board. <P>SOLUTION: In the circuit board having a through hole penetrated into a substrate or a bottomed via hole and allowed to be used for an electronic component, the through hole or the via hole is filled with a metal conductive material by an aerosol deposition method. In the method for manufacturing the circuit board for the electronic component which is provided with the through hole penetrated into the substrate or the bottomed via hole and a connection film passed through the through hole or the via hole: the connection film is formed by filling the through hole or the via hole with the metal conductive material by the aerosol deposition method and a wiring film is formed by forming a conductive metal film by the aerosol deposition method, so that the connection film and the wiring film connected to the connection film are continuously formed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a circuit board for various devices such as a magnetic device, an electronic device, and an optical device having a through hole and a via hole, and a manufacturing method thereof, and particularly relates to a method of forming a conductor film on a through hole. .

  2. Description of the Related Art Conventionally, for example, a circuit board for an electronic device comprises a circuit network formed by baking an Ag-based conductive material or an electrode pad on which an electronic component element is mounted on the surface of a single plate-like substrate such as ceramics. A surface wiring is arranged, and a back surface wiring made of a circuit network or a terminal electrode formed by baking an Ag-based conductive material or the like is arranged on the back surface, and both wirings are connected in the thickness direction of the substrate through a through hole. Configure the network. Also in the case of a multilayer substrate, a through hole or the like is provided in a ceramic substrate, a conductor film is formed on the inner wall thereof to form a through hole / via hole conductor, and a circuit network arranged in each layer is connected by the through hole or the like.

  The through-hole / via-hole conductor part includes a substantially circular through-hole formed in the substrate, an Ag system (Ag alone or Ag alloy such as Ag-Pd) formed on the inner wall of the through-hole, Cu, and the like. It is composed of an inner wall conductor film such as a system (single Cu or Cu alloy) and a land electrode deposited around a through hole or the like.

  The through-hole / via-hole conductor having such a configuration has been formed at the same time when a surface wiring having a predetermined shape is formed on the surface of the substrate, for example. That is, a predetermined circuit pattern including an opening is formed on the surface of the substrate by screen printing using an Ag-based conductive paste. As a result, a conductor film to be a surface wiring is printed on the surface of the substrate, and at the same time, a conductor film to be a land electrode around an opening such as a through hole and a conductor film to be an inner wall conductor film on an inner wall surface of the through hole or the like. Will be applied. Then, after firing and baking the inner wall conductor film and land electrode in the through-hole, etc., fill the opening in the through-hole etc. with the conductive paste for filling, and further bake to connect the front and back wiring ing.

  As another method, Patent Document 1 discloses a method of forming an ultrafine particle film pattern by a so-called gas deposition method. According to this, a mask made of a metal oxide is formed on the circuit board, and ultrafine particles are sprayed into the openings to form an ultrafine particle film pattern, and then the upper surface of the ultrafine particle film pattern is covered, or For example, an Al wiring pattern is formed so as to intersect. And it is disclosed that according to such a structure, a multilayer wiring board can be formed with a conductive ultrafine particle film, and a heat dissipation via hole can be formed with an ultrafine particle film of a good thermal conductor.

JP-A-6-93418

  However, since the opening diameter of a through hole or the like is generally about several tens μm to several hundreds μm μm, and the depth reaches several tens μm to several hundreds μm, when a printing method is employed, a wiring film of several μm is printed. Therefore, it has been difficult to reliably fill such large-diameter through-holes under the conductive paste and printing conditions. Therefore, when trying to fill such a large-diameter through hole, etc., in order to reliably fill the through hole and ensure conduction, this through hole is separated from the conductive paste forming the wiring pattern. A conductive paste for filling such as was required. In addition, since these conductive pastes must be printed separately, the process of forming the wiring film and the process of forming the connection film made of through-holes are separate processes, resulting in complicated manufacturing processes and increased costs. It was. Also, in order to cover the land electrode baked earlier, the through hole or the like is filled with a conductive paste and baked, so that the boundary portion between the land electrode of the baked filled conductor and the inner wall conductor film baked first (through hole) There was also a problem that cracks occurred at the edge portion of holes.

  Further, the film formed using the conductive paste has many defects such as voids, and there is a problem that chipping is likely to occur when post-processing such as polishing is performed for device formation. In addition, the presence of defects such as vacancies has led to a problem that when a plating film is further formed as necessary, the plating solution enters the vacancies and the strength of the plating film is reduced.

  In addition, film deposition by the so-called gas deposition method uses fine particles generated by heating and evaporating metal, which requires a metal heating evaporation device to prepare the raw material fine particles, which complicates the apparatus and manufactures it. It was disadvantageous in cost. In addition, due to the limitation of the ability to supply fine particles due to evaporation, it cannot be said that the film formation speed is particularly high enough to fill large-diameter / deep through-holes. There has been a demand for a film forming method that can be filled.

  The present invention has been devised in view of the above-mentioned problems of the prior art, and its purpose is to reliably fill large-diameter through holes / via holes, and to easily and efficiently provide a circuit board. It is an object to provide a method for forming a high-quality circuit board with few defects.

  In order to solve the above problems, a first invention of the present invention is a method of manufacturing a circuit board for an electronic component having a through hole or a bottomed via hole penetrating a substrate, wherein the through hole or via hole is made of metal. A method of manufacturing a circuit board characterized in that a conductive material is filled by an aerosol deposition method. According to the invention, a large-diameter or deep through-hole can be filled.

  Further, the second invention is a method of manufacturing a circuit board for an electronic component comprising a through hole or a bottomed via hole penetrating a substrate and a connection film passing through the through hole or the via hole. The conductive film is filled with a metal conductive material to form a connection film, and the conductive film is formed by the aerosol deposition method to form a wiring film, whereby the connection film and the connection film are electrically connected. A circuit board manufacturing method is characterized in that a wiring film to be formed is continuously formed. According to this invention, filling of large-diameter or deep through-holes, formation of a wiring film, and reliable connection thereof can be easily realized.

  Furthermore, a third invention is for an electronic component comprising a through hole or a bottomed via hole penetrating a substrate, a connection film passing through the through hole or the via hole, and a wiring film disposed along the surface of the substrate. The circuit board is characterized in that the number of pores having a maximum diameter of more than 2 μm in the cross section of the connection film is 0.1 or less per area of 10 μm in length × 10 μm in width. A highly reliable circuit board with few defects in the connection film or the like can be realized.

  Further, a fourth invention is for an electronic component comprising a through hole or a bottomed via hole penetrating a substrate, a connection film passing through the through hole or the via hole, and a wiring film disposed along the surface of the substrate. The circuit board is characterized in that, in the cross section of the connection film, the maximum diameter of the pores is 2 μm or less, and according to the invention, the connection film or the like has few defects and is highly reliable. A circuit board can be realized.

  Furthermore, a fifth invention is a circuit board according to the third or fourth invention, wherein the connection film and the wiring film are different in composition as a conductive material. A highly reliable circuit board can be realized.

  Further, a sixth invention is characterized in that, in the second invention, the connection film passing through the through hole or via hole and the wiring film arranged along the layer and electrically connected to the connection film have different compositions. According to this invention, a connection film and a wiring film having different functions can be easily and reliably connected.

  Furthermore, a seventh invention is the method of manufacturing a circuit board according to any one of the first, second and sixth inventions, wherein the diameter of the through hole or via hole is in the range of 0.05 mm to 5 mm. With this invention, it is possible to provide a highly reliable circuit board with few connection film defects.

  Further, an eighth invention is the above seventh invention, wherein the diameter of the through hole or via hole is 0.05 mm or more and less than 1 mm, and the average particle size of the metal conductive material raw material powder used for film formation is less than 1 μm. According to another aspect of the present invention, there is provided a method for manufacturing a circuit board. According to the invention, a circuit board with few defects in a connection film and high reliability can be provided.

  Furthermore, a ninth invention is the above seventh invention, wherein the diameter of the through hole or via hole is 1 mm or more and 5 mm or less, and the average particle diameter of the metal conductive material raw material powder used for film formation is 1 μm or more and less than 5 μm. According to another aspect of the present invention, there is provided a method for manufacturing a circuit board, and according to the invention, a circuit board with few connection film defects can be efficiently manufactured.

  Furthermore, in a tenth aspect of the present invention based on any one of the first, second, or sixth to ninth aspects, the metal conductive material is mainly one or more of gold, silver, copper, and aluminum. The circuit board manufacturing method is characterized in that it is a component, and according to this invention, a circuit board having a connection film or the like having further excellent conductivity can be provided.

  Furthermore, in an eleventh aspect of the present invention, in any one of the first, second, or sixth to tenth aspects, the conductor film is heat-treated at a temperature range of a melting point of the metal conductive material from -400 ° C to a melting point of -100 ° C. According to this invention, a higher adhesion strength can be imparted to the connection film while forming the connection film or the like by a simple method.

  As described above, according to the method for manufacturing a circuit board of the present invention using the aerosol deposition method as a conductor film forming method, filling a metal conductive material into a through hole or the like without passing through complicated steps, Formation of a wiring film and continuous formation thereof are possible, contributing to simplification of the manufacturing process and improvement of mass productivity. In particular, it is possible to reliably fill even large-diameter or deep through-holes that have been difficult to fill with conventional methods. Further, since the connection film of the present invention has very few defects, it is possible to provide a highly reliable and high-quality circuit board.

  In the method for manufacturing a circuit board according to the present invention, a conductive film is filled in a through hole / via hole formed in the circuit board by an aerosol deposition method to form a connection film. Furthermore, the through hole / via hole connection film and the conductor film on the substrate surface are continuously formed. That is, a conductive material made of fine metal particles is formed and filled in through holes / via holes of a circuit board by an aerosol deposition method, and a conductor film used as a land electrode or wiring is continuously formed on the substrate surface. Is. In addition to the ceramic substrate, a resin substrate or the like can be used as the circuit substrate. Needless to say, the substrate itself may exhibit physical functions such as a magnetic function and an optical function.

  The aerosol deposition method is a technique in which a fine particle raw material is mixed with a gas to form an aerosol, and this is sprayed onto a substrate at high speed through a thin nozzle. In the present invention, fine particles prepared in advance by mechanical pulverization, chemical synthesis, or the like are used as raw materials, and a so-called narrowly-defined gas device is used in which fine particles generated by heating a metal and evaporating in a gas are directly used for film formation. A distinction is made from the position method.

  Conventionally, for example, the gas deposition method is applied to the formation of a conductive pattern, and the aerosol deposition method is applied to the formation of a functional ceramic film such as PZT (lead zirconate titanate). However, since the aerosol deposition method has a very high film forming speed, it is particularly effective for filling a conductive material into a through hole or a bottomed via hole provided in a circuit board. In addition, in the gas deposition method, since submicron or less ultrafine particles generated by heating and evaporating metal are generally used for film formation, the concentration of gas such as oxygen in the formed film structure tends to be high, The aerosol deposition method, which is prone to thermal stress and tends to cause local cracks and defects, but with different particle supply forms, can suppress these effects and form a conductive film with excellent adhesion and flatness. It is.

The conductor film forming method by the aerosol deposition method will be exemplified with reference to the schematic configuration diagram of the film forming apparatus in FIG. The film forming apparatus includes an aerosol forming chamber 1 for aerosolizing the raw material powder 2, a film forming chamber 4, a transfer pipe 3 connecting between them, and a vacuum exhaust pump 5. In the aerosol generation chamber 1, the raw material powder 2 of metal material fine particles is lifted by the introduced carrier gas 9 and becomes an aerosol. Air, N ₂ , He, Ar, or the like is used as the carrier gas. When metal material fine particles are used as a raw material, it is preferable to use an inert gas to prevent oxidation. The raw material powder 2 is transferred to the film forming chamber 4 through the transfer pipe 3 due to a pressure difference between the aerosol forming chamber 1 and the evacuated film forming chamber 4 and blown out from the nozzle 6 at the tip of the transfer pipe to the substrate 8. Collide and form a coating. Although the carrier gas diffuses immediately, the raw material powder 2 of fine particles is deposited only in the colliding part because of its large mass. In the case of filling a through hole or the like, for example, the nozzle position is aligned with the opening of the through hole, and the aerosolized raw material powder is sprayed for a predetermined time to fill the through hole or the like. Usually, the raw material powder is ejected perpendicularly to the substrate, but it may be ejected at a predetermined angle with respect to the substrate according to the shape of the film-formed portion. It is desirable to use a nozzle that is approximately the same as or larger than the diameter of the through hole. Further, although the wiring pattern can be formed by moving the substrate, the pattern may be formed by lithography using a resist. A substrate having a through hole is reversed and formed on the opposite surface as necessary.

  The through holes and bottomed via holes provided on the circuit board are generally several tens to several hundreds of μm. However, the above-described aerosol deposition method forms a film of 10 μm or more, and further 50 μm or more / minute. Since the speed is possible, it is possible to form a film in a shorter time than film formation by sputtering, CVD, or gas deposition. Further, unlike the gas deposition method using metal fine particles generated by heating and evaporation, the film forming speed is not affected by the fine particle supply ability. Therefore, the aerosol deposition method is particularly effective as a method of filling through holes with a conductive material.

  In addition, in the aerosol deposition method, after filling the through hole, etc., the wiring film including the land electrode can be continuously formed, so the discontinuity between the connection film formed in the through hole and the wiring film Generation of defects and defects can be avoided, and a highly reliable circuit board can be provided. In addition, since the filling of the through holes and the formation of the wiring film can be continuously performed without taking out the substrate from the film formation chamber, the process can be simplified.

  Furthermore, even if the composition of the conductive material used for the connection film and the wiring film formed in the through hole or the like is different, these can be formed continuously as in the case where the compositions are the same. That is, conductive materials having different compositions are continuously formed by changing the type of conductive material put into the aerosolization chamber. Therefore, even when conductive materials having different compositions are formed, it is possible to avoid complication of the process. Therefore, if it is easy to design a film configuration in consideration of physical properties such as electrical resistivity, cost, etc. Close.

  In addition, since the conductor film can be formed at room temperature in the aerosol deposition method, the baking process step required in the printing method using the conductive paste is not required, the cost can be reduced, and the through-hole edge portion can be reduced. Crack generation can be reduced. If necessary, the substrate can be heated to form a film.

  The size of the circuit board's through-holes is also constrained by the design of the circuit board, wiring, etc., but with the aerosol deposition method, the deposition speed is high and the deposition position can be scanned, so a wide aperture It is possible to respond to filling of through holes in the range and depth range. In particular, it is suitable for filling large-diameter or deep through holes that are difficult to fill by a printing method using a conductive paste. In the present invention, the diameter of the through hole or the like is preferably in the range of 0.05 to 5 mm. If the diameter of the through hole or the like is less than 0.05 mm, the through hole or the like is not sufficiently filled with the conductive material, and defects such as nests are likely to occur. On the other hand, when the thickness exceeds 5 mm, for example, when a portion of the conductor film that has run over the substrate surface is polished and removed, chipping or cracking is likely to occur when stress is applied to the connection film formed by filling the through holes. More preferably, by setting the thickness to 0.5 to 3.0 mm, a connection film with fewer defects can be formed. The depth of the through hole or the like is appropriately determined in the substrate design, but is preferably 0.1 to 3.0 mm, more preferably 0.2 to 1.5 mm from the viewpoint of ensuring reliability such as defect reduction. . The opening shape such as a through hole is not particularly limited, and may be an ellipse, a square or the like in addition to a circle. In this case, the shortest opening width such as the minor axis diameter is the diameter of the through hole or the like in the present invention. In addition, the inner wall surface of the through hole or the like is substantially perpendicular to the substrate surface, but in order to improve the adhesion to the substrate, a taper is provided and the diameter of the through hole or the like is increased with respect to the injection direction of the raw material powder. It is also effective to make it smaller. The taper angle θ, that is, the angle formed between the direction perpendicular to the substrate and the inner wall surface of the through hole or the like is preferably 0 <θ ≦ 30 °.

  Moreover, in this invention, the particle size of the raw material powder used for conductor film formation is selected according to the diameter of the said through hole. When the diameter of the through hole or the like is 0.05 mm or more and less than 1 mm, the average particle diameter of the raw material powder used for forming the conductor film is preferably less than 1.0 μm. When the diameter of the through hole is relatively small as 0.05 mm or more and less than 1 mm, if the particle size exceeds the range, it becomes difficult to fill the through hole and the like, and a connection film having sufficient adhesion strength is obtained. I can't. On the other hand, when the diameter of the through hole or the like is 1 mm or more and 5 mm or less, the average particle diameter is preferably 1 μm or more and less than 5 μm. If the average particle size is less than 1 μm, the film formation efficiency is lowered, and therefore it is not preferable for filling through holes with a large diameter. In general, since the raw material powder becomes more expensive as it becomes finer, it is preferable to use an inexpensive raw material powder of 1 μm or more from the viewpoint of cost. On the other hand, when the particle size is 5 μm or more, it becomes difficult to form an aerosol and it is difficult to obtain a dense film. In particular, defects are increased when a wiring film having a thickness smaller than that of the connection film is continuously formed.

  In the present invention, a metal material is used as the conductive material. By using such a metal material, the resistance component can be suppressed and the function as a wiring / conduction line can be sufficiently exhibited. The metal conductive material can be selected according to the substrate material type or application. Here, in order to further suppress the resistance component, it is preferable to use a metal conductive material whose main component is one or more of gold, silver, copper, and aluminum. In addition to conductivity, platinum, palladium, or an alloy containing these can be used to add other functions such as corrosion resistance and solder erosion resistance.

  The conductor film according to the present invention has a sufficient adhesion strength immediately after film formation, but the adhesion strength of the conductive film can be further increased by performing a heat treatment after the film formation. Such heat treatment is performed in a temperature range from the melting point of −400 ° C. to the melting point of −100 ° C. of the deposited metal conductive material. The reason for limiting the heat treatment temperature to such a temperature is that if the heat treatment temperature is lower than the melting point of the metal conductive material −400 ° C., the effect of the heat treatment is not exhibited. This is because a reaction occurs. More preferably, it is melting | fusing point -300-melting | fusing point -200 degreeC.

  In the present invention, an aerosol deposition method is used as a film forming method. By applying the film forming method, a very dense film can be formed. In other words, by applying the aerosol deposition method, it is possible to reduce the number of pores with a maximum diameter of more than 2 μm to 0.1 or less per 10 μm × 10 μm area in the cross section of the connection film formed on the substrate. is there. The maximum width of the hole shape was defined as the maximum diameter, and the number of holes was counted for 10 square fields of 10 μm length × 10 μm width in cross section observation of 1000 times, and the average was used as the number of holes. By setting the pores in the connection film in such a range, high adhesion to the substrate can be ensured, and even when processing such as polishing is performed after film formation, the occurrence of chipping can be suppressed.

  In addition, by applying the aerosol deposition method, the maximum diameter of the pores can be 2 μm or less in the cross section of the connection film formed on the substrate. By setting the vacancies in the connection film in such a range, even when processing such as polishing is performed after film formation, generation of coarse defects such as chips can be suppressed. The maximum diameter of the holes is more preferably 1 μm or less.

  Furthermore, the aerosol deposition method allows the connection film and the wiring film to be formed continuously, so that a substrate with few defects is obtained at the joint, particularly when the composition differs between the connection film and the wiring film. be able to. The connection film and the wiring film may require different material characteristics due to the difference in function. However, for example, when the connection film and the wiring film are made of metal conductive materials having different compositions by the printing method or the printing method and the plating method, it is necessary to form each film in a separate process. Defects such as cracks are likely to occur, and it is difficult to obtain a highly reliable substrate. On the other hand, when the connection film and the wiring film are continuously formed of metal conductive materials having different compositions by the aerosol deposition method, not only each film but also its interface can have few defects. Therefore, by adopting such a configuration of the connection film and the wiring film, a circuit board having both high reliability and high function can be provided.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, referring a figure, this invention is not limited by these Examples.

  First, a through hole 101 having a diameter of 3 mm was formed in a ceramic substrate 100 having a thickness of 0.8 mm (FIG. 2A).

  Next, a dicing tape 104 was attached to the back surface of the ceramic substrate 100 in which the through hole 101 was formed (FIG. 2B).

  The ceramic substrate 100 with the dicing tape 104 attached to the back surface was fixed to the stage (substrate holder) 8 of the film deposition apparatus (FIG. 1) by the aerosol deposition method so that the surface of the ceramic substrate 100 faced downward.

Silver fine particles having an average particle diameter of 1 μm were arranged as the raw material powder 2 in the aerosol chamber 1, and N ₂ was prepared as the carrier gas 9. Further, the nozzle 6 having a width of 5.0 mm and a slot width of 0.5 mm was used.

After setting the substrate, the raw material powder, and the nozzle, the film formation chamber 4 and the aerosol generation chamber 1 were evacuated (roughened) with a rotary pump, and further evacuated with a mechanical booster pump. The degree of vacuum at this time was 1 × 10 ⁻¹ Pa. Further, the aerosolization chamber 1 was vibrated and N ₂ of the carrier gas 9 was introduced into the aerosolization chamber 1 to aerosolize silver fine particles, and then transferred to the film formation chamber 4 through the transfer tube 3. At this time, the stage (substrate holder) 8 was scanned slightly wider than the diameter of the through hole 101, and the inside of the through hole 101 was filled with silver fine particles.

  Further, the scanning width of the stage (substrate holder) 8 is widened, and a conductive film made of silver fine particles is formed on the surface of the ceramic substrate 100 (FIG. 2C). The time required for the film formation was 11 minutes.

  After forming the conductive film, the dicing tape 104 on the back surface of the ceramic substrate 100 on which the conductive film was formed with silver fine particles in the through hole 101 was peeled off. Next, the surface of the ceramic substrate 100 was aligned with the stage (substrate holder) 8 to fix the ceramic substrate.

  Similarly to the surface, a conductive film made of silver fine particles was formed on the surface of the ceramic substrate 100, and a circuit board was obtained in which the front surface wiring and the back surface wiring were electrically connected through the connection film formed in the through hole (FIG. 2). (d)).

  Next, polishing treatment was performed on both surfaces of the ceramic substrate (FIG. 2 (e)). FIG. 3 shows a cross-sectional polished photograph of the through-hole connection film 11 of the substrate thus obtained, and FIG. 4 shows a schematic diagram in which the main part of the photograph of FIG. 3 is copied. Further, as a comparative example, after a silver paste is screen-printed, a cross-sectional polishing photograph of a conductor film by a printing method obtained by baking at 800 ° C. is shown in FIG. 5, and a schematic diagram in which a main part of the photograph of FIG. As shown in FIG. As is apparent from FIG. 3, the conductor film obtained by the aerosol deposition method is very dense as compared with that obtained by the printing method, and the number of pores 13 is extremely small. Also, the surface 12 could be formed flat. When formed by the aerosol deposition method, the number of pores having a maximum diameter exceeding 2 μm per area of 10 μm in length × 10 μm in width was 0.1. That is, it can be seen that the number of coarse pores having a maximum diameter exceeding 2 μm can be significantly reduced by the aerosol deposition method, and the number can be reduced to 0.1 or less. On the other hand, in the conductive film 15 of the comparative example, the number of holes 18 and 19 having a maximum diameter exceeding 2 μm per area of 10 μm in length × 10 μm in width was 1.1. The conductor film 15 was formed on the substrate 16. Reference numeral 17 denotes a tissue observation resin, which is laminated on the surface of the conductor film 15 of the comparative example.

It is the schematic of the film-forming apparatus by the aerosol deposition method of this invention. (A)-(e) is a schematic sectional drawing of the board | substrate which shows the conductor film formation method to the through hole by this invention. It is the optical microscope photograph which observed the cross section of the through-hole connection film | membrane of this invention. It is the schematic diagram which copied the principal part of the photograph of FIG. It is the optical microscope photograph which observed the cross section of the through-hole connection film | membrane of a comparative example. It is the schematic diagram which copied the principal part of the photograph of FIG.

Explanation of symbols

1 aerosolization chamber 2 raw material powder 3 transfer tube 4 deposition chamber 5 vacuum pump
6 nozzles, 7 stages (substrate holder), 8 substrates, 9 carrier gas,
11 through-hole connection film, 12 film surface, 13 holes,
15 conductor film, 16 substrate, 17 structure observation resin, 18 holes, 19 holes,
100 ceramic substrate, 101 through hole, 103 filled conductor film,
104 dicing tape

Claims (5)

A method of manufacturing a circuit board for an electronic component having a through hole or a bottomed via hole penetrating a substrate, wherein the metal conductive material is filled into the through hole or the via hole by an aerosol deposition method. Circuit board manufacturing method. A method of manufacturing a circuit board for an electronic component comprising a through hole or a bottomed via hole penetrating a substrate and a connection film passing through the through hole or the via hole, wherein a metal conductive material is formed by an aerosol deposition method. Filling to form a connection film and forming a wiring film by forming a conductive metal by the aerosol deposition method, thereby continuously connecting the connection film and the wiring film electrically connected to the connection film A method for manufacturing a circuit board, comprising: A circuit board for an electronic component comprising a through hole or a bottomed via hole penetrating a substrate, a connection film passing through the through hole or the via hole, and a wiring film disposed along the surface of the substrate, A circuit board characterized in that the number of pores having a maximum diameter of more than 2 μm in the cross section of the connection film is not more than 0.1 per 10 μm × 10 μm area. A circuit board for an electronic component comprising a through hole or a bottomed via hole penetrating a substrate, a connection film passing through the through hole or the via hole, and a wiring film disposed along the surface of the substrate, A circuit board having a maximum diameter of pores of 2 μm or less in a cross section of the connection film. 5. The circuit board according to claim 3, wherein the connection film and the wiring film have different compositions as conductive materials.

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