JP2014207322A - Manufacturing method of component built-in printed wiring board, and component built-in printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve yield of a component built-in printed wiring board by improving connection reliability of a via electrically connecting a built-in electronic component and an outside wiring layer.SOLUTION: A manufacturing method of a component built-in printed wiring board 1 includes the steps of: forming, on a principal surface 4a of an insulation substrate 4, an adhesive layer 6 which does not contain a filler and of which the plane size is equal to or smaller than that of an electronic component 2; packaging the electronic component 2 on the adhesive layer 6; hardening the adhesive layer 6; preparing a component filling material 7 which contains a filler 8 but does not contain any material of which the particle size is equal to or smaller than a gap between the electronic component 2 and the insulation substrate 4, as the filler 8; heating and pressurizing a laminate formed by holding the component filling material 7 between a metal-clad laminate plate 3 and a cover material 9 and integrating the laminate; forming a via hole 11 in which a terminal part 2a of the electronic component 2 on a bottom face, by irradiation with laser light; and forming a via 14 electrically connecting a metal foil 5 and the terminal part 2a.

Description

  The present invention relates to a printed wiring board with a built-in component, and more specifically, a printed wiring board with a built-in component in which a surface-mount type electronic component is built and a via is provided to electrically connect the built-in electronic component and an outer wiring layer. The present invention relates to a board manufacturing method and a component built-in printed wiring board.

  Along with the recent downsizing, thinning, and high functionality of electronic devices, there has been an increasing trend to increase the functionality of printed wiring boards by mounting electronic components on printed wiring boards at high density. Under such circumstances, a component built-in printed wiring board in which electronic components are embedded is known.

  In the component built-in printed wiring board, since electronic components such as a semiconductor chip and a capacitor are embedded inside, the area of the printed wiring board can be reduced. In addition, since the degree of freedom for arranging electronic components is increased as compared with the case of a normal printed wiring board, a plurality of electronic components can be connected at the shortest distance. As a result, parasitic inductance and the like are reduced, and high-frequency characteristics can be improved.

  In the component built-in printed wiring board, securing the connection reliability of vias that electrically connect the built-in electronic component and the outer wiring layer is important in improving the yield.

  In Patent Document 1, in a component built-in printed wiring board in which a plurality of electronic components having different thicknesses are embedded, the heights of the electronic components are made uniform by using concave portions and spacer members provided in the substrate, and the via depth is made uniform. A method for improving the yield is described.

JP 2004-128002 A

  However, when the method of Patent Document 1 is adopted, it is necessary to provide a recess in the substrate or fix a spacer, so that the manufacturing process becomes complicated and the manufacturing cost may increase.

  Even if the depth of the via is made constant, unless the mounting position accuracy of the electronic component is ensured, the via connection reliability cannot be ensured and the yield cannot be improved. This will be described in detail with reference to FIG. FIG. 4 is a process cross-sectional view for explaining a conventional method of manufacturing a component built-in printed wiring board.

  First, a single-sided copper clad laminate 103 having an insulating base 104 made of polyimide, glass epoxy, or the like and a copper foil 105 provided on one side of the insulating base 104 is prepared. Then, a predetermined portion of the copper foil 105 is removed by etching, thereby forming a via-forming conformal mask 105a as shown in FIG. At this time, an alignment target mark is formed.

  Next, using an alignment target mark formed simultaneously with the conformal mask 105a, as shown in FIG. 4A, an adhesive is printed at a predetermined position of the insulating base 104, and the adhesive layer 106 is formed. Form. The adhesive layer 106 has a larger planar size than the electronic component 102 mounted on the adhesive layer 106.

  Next, as shown in FIG. 4A, the surface-mount type electronic component 102 is mounted on the adhesive layer 106 with a mounter, and the adhesive layer 106 is thermally cured until the electronic component 102 is fixed. The planar size of the electronic component 102 is, for example, 0.6 mm × 0.3 mm, and the planar size of the terminal portion (electrode) 102a of the electronic component 102 is approximately 0.2 mm × 0.3 mm.

  When the adhesive layer 106 is thermally cured, as shown in FIGS. 4A and 4B, the mounting position of the electronic component 102 may be shifted. This misalignment is considered to occur when the adhesive layer 106 is once reduced in viscosity before the start of curing and then cured unevenly. When the adhesive layer 106 is lowered in viscosity, the electronic component 102 having a smaller planar size than the adhesive layer 106 is in a state of swimming in the adhesive layer 106. It is considered that the position will be displaced.

  Next, a component filler 109 and a single-sided copper clad laminate 110 are prepared. The single-sided copper-clad laminate 110 has an insulating base 110a and a copper foil 110b provided on one side of the insulating base 110a. Then, as shown in FIG. 4 (2), a single-sided copper-clad laminate 103 on which electronic components 102 are mounted, a component filler 109, and a single-sided copper-clad laminate 110 are laminated in this order to form a laminate. Then, the laminated body is integrated by heating and pressurizing the laminated body.

Next, as shown in FIG. 4C, via holes 107 for forming vias are formed by laser processing using the conformal mask 105a. A CO ₂ laser or the like is used for this laser processing. Further, a through hole 112 for forming a plated through hole is formed by a drill.

  As described above, the mounting position of the electronic component 102 is shifted from the initial position in the process of curing the adhesive layer 106. For this reason, as shown in FIG. 4 (3), parts other than the terminal portion 102a of the electronic component 102 (component filler 109, main body portion of the electronic component 102, etc.) are exposed at the bottom of the via hole 107. The shape of the via hole 107 is not stable.

  Next, as shown in FIG. 4 (4), after the desmear process using permanganic acid or the like is performed on the via hole 107 and the through hole 112, the conductive process and the subsequent electrolytic copper plating process are performed. A plating film 113 is formed. The plating film 113 formed on the inner wall of the via hole 107 constitutes a via 108 that electrically connects the electronic component 102 and the copper foil 105. Further, the plating film 113 formed on the inner wall of the through hole 112 constitutes a plated through hole 114 that electrically connects the copper foil 105 and the copper foil 110b.

  Thereafter, by using a known photofabrication technique, the conductive film made of the copper foil 105 and the copper plating film 113 is patterned to form an outer wiring layer (not shown). As a result, a component built-in printed wiring board in which the electronic component 102 and the outer wiring layer are electrically connected by the via 108 is obtained.

  When the component built-in printed wiring board is manufactured by the above manufacturing method, the mounting position of the electronic component 102 may deviate from the initial position when the adhesive layer 106 is cured as described above. In such a case, the shape of the via hole 107 is not stable, and the material to be removed by laser processing is not stable, so that the laser processability is deteriorated. Therefore, the connection reliability of the via 108 formed in the via hole 107 is lowered, leading to a decrease in the yield of the component built-in printed wiring board.

  In order to increase the mounting position accuracy of the electronic component 102, it is conceivable to make the planar size of the adhesive layer 106 smaller than the planar size of the electronic component 102. However, in practice, the component filler 109 generally contains a filler 109a in order to ensure the flatness of the component built-in printed wiring board. As shown in FIG. 5A, the filler 109 a having a small particle size may enter between the electronic component 102 and the insulating base material 104. In this case, the filler is included in the region to be removed by the laser when forming the via hole 107, and the laser workability of the via hole 107 is lowered. As a result, the connection reliability of the via 108 is lowered.

  Further, as shown in FIG. 5B, also when the adhesive layer 106 contains the filler 106a, the laser workability of the via hole 107 is deteriorated. Further, the electronic component 102 may be mounted with an inclination with respect to the insulating substrate 104 due to variations in the particle size and density of the filler. Also in this case, the shape of the via hole 107 becomes unstable, and the connection reliability of the via 108 is lowered.

  The present invention has been made based on the above technical recognition, and in the printed wiring board with built-in components, improves the connection reliability of vias that electrically connect the built-in electronic components and the outer wiring layer. An object is to improve the yield of printed wiring boards with built-in components.

The method of manufacturing a component built-in printed wiring board according to the present invention includes:
A method for manufacturing a component-embedded printed wiring board in which surface-mount type electronic components are incorporated,
A metal-clad having an insulating base material having a first main surface and a second main surface opposite to the first main surface, and a metal foil provided on the second main surface of the insulating base material Preparing a laminate, and
An adhesive layer forming step of forming an adhesive layer containing no filler and having a planar size equal to or smaller than the planar size of the electronic component on the first main surface of the insulating substrate;
An electronic component mounting step of mounting the electronic component on the adhesive layer;
Curing the adhesive layer such that the electronic component is secured to the insulating substrate by the adhesive layer;
Containing a filler, and preparing a filler as a filler that does not contain a particle size equal to or less than the gap between the electronic component and the insulating base;
The electronic component is embedded in the component filler by heating and pressurizing the laminate with the component filler sandwiched between the metal-clad laminate and the cover material to integrate the laminate. Producing a component-embedded substrate,
A laser processing step of forming a via hole that penetrates the insulating base material in the thickness direction and exposes the terminal portion of the electronic component on the bottom surface by irradiating the component built-in base material with laser light;
Forming a via for electrically connecting the metal foil and the terminal portion of the electronic component;
It is characterized by providing.

The printed wiring board with built-in components according to the present invention is
An insulating substrate having a first main surface and a second main surface opposite to the first main surface;
An adhesive layer formed on the first main surface of the insulating substrate;
A surface-mounted electronic component fixed to the insulating base material by the adhesive layer;
A component filler that is provided on the first main surface of the insulating substrate and embeds the electronic component;
A cover material for sandwiching the component filler together with the insulating substrate;
A wiring layer provided on the second main surface of the insulating base;
A via that penetrates the insulating base material in the thickness direction and exposes a terminal portion of the electronic component on the bottom surface, and a via that electrically connects the terminal portion and the wiring layer;
With
The adhesive layer does not contain a filler, the plane size is equal to or less than the plane size of the electronic component,
The component filler contains a filler, and as the filler, the particle size does not contain the gap between the electronic component and the insulating base material,
It is characterized by that.

  In the present invention, the adhesive layer has a planar size equal to or smaller than the planar size of the electronic component. Thereby, it is possible to prevent the electronic component from being displaced when the adhesive layer is cured, and to realize high mounting position accuracy. As a result, the shape of the via hole can be stabilized and the laser workability of the via hole can be improved.

  Moreover, in this invention, a component filler contains a filler and does not contain a thing with a particle size below the clearance gap between an electronic component and an insulation base material as this filler. This prevents the filler of the component filler from entering the gap between the electronic component and the insulating substrate in the process of producing the component-embedded substrate. Therefore, even when the planar size of the adhesive layer is smaller than the planar size of the electronic component, the filler is not included in the region to be removed by laser processing when forming the via hole. That is, even when the planar size of the adhesive layer is smaller than the planar size of the electronic component, it is possible to prevent the laser hole processability of the via hole from being lowered.

  Furthermore, in this invention, the adhesive bond layer which fixes an electronic component to an insulating base material does not contain a filler. Thereby, the film thickness of the adhesive layer is made uniform, and the electronic component is prevented from being tilted and fixed with respect to the insulating base material due to variations in the particle size and density of the filler. Therefore, the shape of the via hole can be stabilized and the laser workability of the via hole can be improved.

  As described above, since the shape of the via hole can be stabilized and the laser workability of the via hole can be improved, according to the present invention, the connection of the via that is formed in the via hole and electrically connects the electronic component and the wiring layer. Reliability can be improved. As a result, the yield of the component built-in printed wiring board can be improved.

It is process sectional drawing for demonstrating the manufacturing method of the component built-in printed wiring board which concerns on one Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the component built-in printed wiring board which concerns on one Embodiment of this invention following FIG. (A) is sectional drawing of the component built-in printed wiring board which concerns on one Embodiment of this invention, (b) is a top view of the metal-clad laminated board in the electronic component mounting state of FIG. 1 (2). It is process sectional drawing for demonstrating the manufacturing method of the conventional component built-in printed wiring board. (A) is sectional drawing of the conventional component built-in printed wiring board in case a filler is contained in a component filler, (b) is the conventional electronic component mounting state in case a filler is contained in an adhesive bond layer. It is sectional drawing of a single-sided copper clad laminated board.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the component which has an equivalent function is attached | subjected the same code | symbol, and detailed description of the component of the same code | symbol is not repeated. Further, the drawings are schematic and show mainly the characteristic portions according to the embodiment, and the relationship between the thickness and the planar dimension, the ratio of the thickness of each layer, and the like are different from the actual ones.

  With reference to FIGS. 1-3, the manufacturing method of the component built-in printed wiring board 1 which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a process cross-sectional view for explaining a method of manufacturing the component built-in printed wiring board 1. FIG. 2 is a process cross-sectional view for explaining the manufacturing method of the component built-in printed wiring board 1 following FIG. FIG. 3A is a cross-sectional view of the component built-in printed wiring board 1. FIG.3 (b) has shown the top view of the metal-clad laminated board in the electronic component mounting state of FIG.1 (2).

  First, as shown in FIG. 1 (1), an insulating base 4 having a main surface 4a and a main surface 4b opposite to the main surface 4a, and a metal foil 5 provided on the main surface 4b of the insulating base 4, A metal-clad laminate 3 having is prepared. The metal-clad laminate 3 is, for example, a single-sided copper-clad laminate having a 25 μm-thick polyimide film as the insulating substrate 4 and a 12 μm-thick electrolytic copper foil as the metal foil 5.

  The insulating base 4 may be made of a flexible substrate material such as polyimide, or a hard substrate material such as glass epoxy or aramid material. Further, the metal foil 5 is not limited to the copper foil but may be made of other metals (silver, aluminum, etc.).

  Next, as shown in FIG. 1A, a conformal mask 5 a (for example, φ70 μm) for forming vias is formed on the metal foil 5 of the metal-clad laminate 3. At this time, it is preferable to form target marks (component mounting targets and the like) for various alignments. The patterning of the metal foil 5 in this step is performed by, for example, a known photofabrication technique.

  Next, as shown in FIG. 1 (1), an adhesive layer 6 containing no filler is formed on the main surface 4a of the insulating base 4 (adhesive layer forming step).

  The planar size of the adhesive layer 6 is equal to or smaller than the planar size of the electronic component 2. For example, the planar size of the adhesive layer 6 is 0.4 mm × 0.1 mm.

  The adhesive layer 6 is formed by printing an adhesive containing no filler on a predetermined portion of the insulating substrate 4 using a printing method such as screen printing. The adhesive may be thermosetting or UV curable. The thickness of the adhesive layer 6 is, for example, 30 μm.

  In addition, you may form the adhesive bond layer 6 using printing methods other than screen printing, for example, inkjet printing, a dispensing method, a transfer method etc.

  The adhesive layer 6 is not limited to being formed by a printing method. For example, the adhesive layer 6 may be formed by patterning the adhesive sheet after bonding the adhesive sheet to the insulating substrate 4 so as to cover the main surface 4a.

  Next, as shown in FIGS. 1B and 3B, the surface mount type electronic component 2 is mounted on the adhesive layer 6 using a mounter or the like (electronic component mounting step). The electronic component 2 is mounted based on, for example, the position of the component mounting target described above.

  As shown in FIG. 3B, the electronic component 2 is mounted so that the conformal mask 5 a is included in the terminal portion (electrode) 2 a of the electronic component 2 when viewed in the thickness direction of the metal-clad laminate 3. Preferably, the electronic component 2 is mounted so that the conformal mask 5a overlaps the central portion of the terminal portion 2a when viewed in the thickness direction of the metal-clad laminate 3.

  The planar size of the electronic component 2 is, for example, 0.6 mm × 0.3 mm, and the thickness is, for example, 330 μm. The planar size of the terminal part (electrode) 2a is, for example, 0.2 mm × 0.3 mm.

  Next, the adhesive layer 6 is cured so that the electronic component 2 is fixed to the insulating substrate 4 by the adhesive layer 6. When the adhesive layer 6 is made of a thermosetting adhesive, the adhesive layer 6 is cured by heating under a predetermined condition (for example, 175 ° C./60 minutes).

  Next, the component filler 7 and the cover material 9 are prepared. The cover material 9 is, for example, the same metal-clad laminate as the metal-clad laminate 3. That is, the cover material 9 includes an insulating base material 9a and a metal foil 9b provided on the insulating base material 9a. In addition, as the cover material 9, you may use the insulation base material (resin sheet etc.) which does not have metal foil.

  The component filler 7 is, for example, an adhesive in a curing intermediate state (B stage). The component filler 7 is preferably thicker than the electronic component 2 because it is necessary to embed the electronic component 2 while ensuring the flatness of the component built-in printed wiring board 1. For example, the component filler 7 having a thickness of 350 μm is prepared for the electronic component 2 having a thickness of 330 μm.

  In order to ensure the flatness of the component built-in printed wiring board 1, the component filler 7 includes a filler 8. More specifically, the component filler 7 does not contain a filler 8 having a particle size equal to or smaller than the gap between the electronic component 2 and the insulating substrate 4. In other words, the minimum particle size of the filler 8 contained in the component filler 7 is larger than the gap between the electronic component 2 and the insulating substrate 4. The “gap” as used in the present invention is a distance between the insulating base material 4 and the electronic component fixed to the insulating base material 4 by the cured adhesive layer 6.

  For example, since the thickness of the adhesive layer 6 after curing is about 5 μm to 10 μm, the particle size of the filler 8 is preferably 15 μm or more and 50 μm or less.

  Next, as shown in FIGS. 1 (3) and 2 (4), the laminated body in which the component filler 7 is sandwiched between the metal-clad laminate 3 and the cover material 9 is heated and pressed to be laminated. Integrate the body. Thereby, as shown in FIG. 2 (4), the component-embedded base material 10 in which the electronic component 2 is embedded in the component filler 7 is produced.

  The heating / pressurizing conditions in this step are, for example, a lamination temperature (heating temperature) of 175 ° C., a lamination pressure (pressurization pressure) of 2.0 MPa, and a lamination time of 60 minutes.

  Next, as shown in FIG. 2 (5), the via hole 11 is formed by irradiating the component built-in base material 10 with laser light (laser processing step). More specifically, the via hole 11 is formed by removing the insulating base material 4 exposed to the conformal mask 5a by a so-called conformal laser processing method.

The via hole 11 is a conduction hole that penetrates the insulating base material 4 in the thickness direction, and the terminal portion 2a of the electronic component 2 is exposed on the bottom surface. In addition, as a laser to be used, a UV-YAG laser, an excimer laser, or the like can be used in addition to the CO ₂ laser.

  As shown in FIG. 2 (5), the through-hole 12 that penetrates the component-embedded substrate 10 in the thickness direction may be formed using a drill or the like.

  The material removed by laser processing when forming the via hole 11 differs depending on the size of the planar size of the adhesive layer 6. This will be described in detail.

  The first case is a case where the adhesive layer 6 is formed to have approximately the same size as the planar size of the electronic component 2. In this case, the insulating substrate 4 and the adhesive layer 6 are removed by laser processing to form the via hole 11. In the second case, as shown in FIGS. 2 (4) and 3 (b), the outer edge portion of the adhesive layer 6 is present in the conformal mask 5a when viewed in the thickness direction of the component-embedded base material 10. There is a case. In this case, the insulating base material 4, the adhesive layer 6 and the component filler 7 are removed by laser processing to form the via hole 11. The third case is a case where the adhesive layer 6 is formed as a small area that contacts only the main body between the terminal portions 2a, 2a of the electronic component 2. In this case, the insulating base material 4 and the component filler 7 are removed by laser processing to form the via hole 11.

  Next, as shown in FIG. 2 (6), a via 14 that electrically connects the metal foil 5 and the terminal portion 2 a of the electronic component 2 is formed.

  Specifically, a desmear process is performed to remove resin residues in the via hole 11 and the through hole 12, and then a conductive process and a subsequent plating process are performed. This plating process is, for example, an electrolytic copper plating process, but other plating methods may be used. Thereby, the plating film 13 is formed on the inner walls of the via holes 11 and the through holes 12 and the metal foils 5 and 9b. Here, the thickness of the plating film 13 was 20 μm.

  The plating film 13 formed on the inner wall of the via hole 11 constitutes a via 14 that electrically connects the electronic component 2 and the metal foil 5. As shown in FIG. 2 (6), the via 14 is provided immediately above the terminal portion 2 a of the electronic component 2. Further, the plating film 13 formed on the inner wall of the through hole 12 constitutes a plated through hole 15 that electrically connects the metal foil 5 and the metal foil 9b.

  Next, as shown in FIG. 3A, the wiring layer 16 is formed by patterning the conductive film made of the metal foil 5 and the plating film 13 using a known photofabrication technique. Similarly, the wiring layer 17 is formed by patterning the conductive film composed of the metal foil 9 b and the plating film 13.

  Through the above steps, the component built-in printed wiring board 1 shown in FIG.

  This component built-in printed wiring board 1 includes an insulating base 4, an adhesive layer 6 formed on the main surface 4 a of the insulating base 4, and a surface mount type fixed to the insulating base 4 by the adhesive layer 6. The electronic component 2, the component filler 7 provided on the main surface 4 a of the insulating substrate 4, and the electronic component 2 embedded therein, the cover material 9 sandwiching the component filler 7 together with the insulating substrate 4, and the insulating substrate 4, the wiring layer 16 provided on the main surface 4b, and the via hole 11 that penetrates the insulating base material 4 in the thickness direction and exposes the terminal portion 2a of the electronic component 2 on the bottom surface, and the terminal portion 2a and the wiring layer And vias 14 that electrically connect 16 to each other.

  In the component built-in printed wiring board 1, the adhesive layer 6 does not contain a filler, and the planar size is equal to or smaller than the planar size of the electronic component 2. Further, the component filler 7 contains a filler 8, and the filler 8 does not contain a filler having a particle size equal to or smaller than the gap between the electronic component 2 and the insulating base material 4.

  As described above, in the present embodiment, the adhesive layer 6 has a planar size equal to or smaller than the planar size of the electronic component 2. Thereby, when the adhesive bond layer 6 is hardened, it is possible to prevent the electronic component 2 from being displaced, and to improve the mounting accuracy of the electronic component 2. Therefore, for example, things other than the terminal portion 2a (such as the component filler 7 and the main body portion of the electronic component 2) are not exposed on the bottom surface of the via hole. As a result, the shape of the via hole 11 can be stabilized and the laser processability of the via hole 11 can be improved.

  Further, in the present embodiment, the component filler 7 includes a filler 8, and the filler 8 does not include a filler having a particle size equal to or smaller than the gap between the electronic component 2 and the insulating base 4. This prevents the filler 8 from entering the gap between the electronic component 2 and the insulating substrate 4 in the process of manufacturing the component-embedded substrate 10. Therefore, even when the planar size of the adhesive layer 6 is smaller than the planar size of the electronic component 2, the filler is not included in the region to be removed by laser processing when the via hole 11 is formed. That is, even when the planar size of the adhesive layer 6 is smaller than the planar size of the electronic component 2, it is possible to prevent the laser workability of the via hole 11 from being deteriorated.

  Furthermore, in this embodiment, the adhesive layer 6 that fixes the electronic component 2 to the insulating base 4 does not contain a filler. Thereby, the thickness of the adhesive bond layer 6 is made uniform. Further, the electronic component 2 is prevented from being tilted and fixed with respect to the insulating base material 4 due to variations in the particle size and density of the filler. That is, the electronic component 2 is mounted substantially parallel to the insulating base 4. Furthermore, the physical properties of the adhesive layer 6 in the portion removed by laser processing are made uniform. Therefore, the shape of the via hole 11 can be stabilized and the laser workability of the via hole 11 can be improved.

  Thus, according to the present embodiment, the shape of the via hole 11 can be stabilized and the laser workability of the via hole 11 can be improved. Therefore, the connection reliability of the via 14 formed in the via hole 11 can be improved. As a result, the yield of the component built-in printed wiring board 1 can be improved.

  The component filler 7 is preferably made of a material having the same composition as the adhesive layer 6. For example, the component filler 7 is obtained by adding a filler 8 to an adhesive for forming the adhesive layer 6. By using the same composition, the material removed by laser processing does not change according to the planar size of the adhesive layer 6. For this reason, the laser processability of the via hole 11 can be further improved, and the connection reliability of the via 14 can be further improved.

  In the description of the above embodiment, the via hole 11 is formed by a conformal processing method using the metal foil 5 as a metal mask. However, the present invention is not limited to this, and for example, the via hole 11 is formed by a direct laser processing method. May be.

  When the direct laser processing method is used, the via hole 11 is formed by directly irradiating the metal foil 5 of the metal-clad laminate 3 with laser light in the laser processing step described above. More specifically, using a target mark (laser target) formed by patterning the metal foil 5, the metal foil 5 and the insulating substrate 4 are removed by irradiating a predetermined position of the metal foil 5 with laser light. A via hole 11 is formed by the above.

  Further, the gap between the electronic component 2 and the insulating base 4 is adjusted or controlled by the material of the adhesive layer 6, the thickness before curing, the conditions for curing the adhesive layer 6, the mounting load of the electronic component 2 by the mounter, and the like. Is possible. Therefore, by adjusting or controlling these parameters, the minimum particle size of the filler 8 included in the given component filler 7 may be made larger than the gap between the electronic component 2 and the insulating substrate 4. Good.

  Further, the metal-clad laminate 3 is not limited to a single-sided metal-clad laminate, and may be a double-sided metal-clad laminate in which a metal foil is also provided on the main surface 4a of the insulating base 4. Similarly, the cover material 9 is not limited to a single-sided metal-clad laminate, and may be a double-sided metal-clad laminate in which metal foil is provided on both sides of the insulating base material 9a.

  Based on the above description, those skilled in the art may be able to conceive additional effects and various modifications of the present invention, but the aspects of the present invention are not limited to the above-described embodiments. Various additions, modifications, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Component built-in printed wiring board 2 Electronic component 2a Terminal part 3 Metal-clad laminated board 4 Insulating base material 4a, 4b Main surface 5 Metal foil 5a Conformal mask 6 Adhesive layer 7 Component filler 8 Filler 9 Cover material 9a Insulating base material 9b Metal foil 10 Component built-in base material 11 Via hole 12 Through hole 13 Plating film 14 Via 15 Plating through hole 16, 17 Wiring layer 102 Electronic component 102a Terminal portion 103 Single-sided copper clad laminate 104 Insulating base material 105 Copper foil 105a Conformal mask 106 Adhesive layer 106a Filler 107 Via hole 108 Via 109 Component filler 109a Filler 110 Single-sided copper clad laminate 110a Insulating substrate 110b Copper foil 112 Through hole 113 Copper plating film 114 Plating through hole

Claims (7)

A method for manufacturing a component-embedded printed wiring board in which surface-mount type electronic components are incorporated,
A metal-clad having an insulating base material having a first main surface and a second main surface opposite to the first main surface, and a metal foil provided on the second main surface of the insulating base material Preparing a laminate, and
An adhesive layer forming step of forming an adhesive layer containing no filler and having a planar size equal to or smaller than the planar size of the electronic component on the first main surface of the insulating substrate;
An electronic component mounting step of mounting the electronic component on the adhesive layer;
Curing the adhesive layer such that the electronic component is secured to the insulating substrate by the adhesive layer;
Containing a filler, and preparing a filler as a filler that does not contain a particle size equal to or less than the gap between the electronic component and the insulating base;
The electronic component is embedded in the component filler by heating and pressurizing the laminate with the component filler sandwiched between the metal-clad laminate and the cover material to integrate the laminate. Producing a component-embedded substrate,
A laser processing step of forming a via hole that penetrates the insulating base material in the thickness direction and exposes the terminal portion of the electronic component on the bottom surface by irradiating the component built-in base material with laser light;
Forming a via for electrically connecting the metal foil and the terminal portion of the electronic component;
A method of manufacturing a printed wiring board with built-in components, comprising:   The method for manufacturing a component built-in printed wiring board according to claim 1, wherein the component filler is made of a material having the same composition as the adhesive layer.   3. The method of manufacturing a component built-in printed wiring board according to claim 1, wherein a particle size of the filler contained in the component filler is 15 μm or more and 50 μm or less. Further comprising forming a conformal mask on the metal foil of the metal-clad laminate,
In the electronic component mounting step, the electronic component is mounted on the adhesive layer so that the conformal mask is included in the terminal portion of the electronic component when viewed in the thickness direction of the metal-clad laminate. ,
4. The component built-in printed wiring board according to claim 1, wherein in the laser processing step, the via hole is formed by removing the insulating base material exposed to the conformal mask. 5. Production method.   In the laser processing step, the via hole is formed by irradiating the metal foil of the metal-clad laminate with a laser beam to remove the metal foil and the insulating base material. 4. A method for producing a component built-in printed wiring board according to any one of 3 above. An insulating substrate having a first main surface and a second main surface opposite to the first main surface;
An adhesive layer formed on the first main surface of the insulating substrate;
A surface-mounted electronic component fixed to the insulating base material by the adhesive layer;
A component filler that is provided on the first main surface of the insulating substrate and embeds the electronic component;
A cover material for sandwiching the component filler together with the insulating substrate;
A wiring layer provided on the second main surface of the insulating base;
A via that penetrates the insulating base material in the thickness direction and exposes a terminal portion of the electronic component on the bottom surface, and a via that electrically connects the terminal portion and the wiring layer;
With
The adhesive layer does not contain a filler, the plane size is equal to or less than the plane size of the electronic component,
The component filler contains a filler, and as the filler, the particle size does not contain the gap between the electronic component and the insulating base material,
A printed wiring board with built-in components.   The component-embedded printed wiring board according to claim 6, wherein the component filler is made of a material having the same composition as the adhesive layer.

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