JPWO2013046500A1 - Manufacturing method of electronic component module - Google Patents

Abstract

A step of preparing a core layer having a component mounting surface on which a first wiring pattern is formed; a step of roughening a surface of the first wiring pattern; and a portion covering at least a land of the first wiring pattern after the roughening, A step of arranging a bonding material including a thermosetting resin and solder particles, and preparing an electronic component having a terminal, landing the terminal on the land via the bonding material, and mounting the electronic component on the component mounting surface First, the core layer on which the electronic component is mounted is heated first, the terminal is bonded to the land with solder, the thermosetting resin is semi-cured, and the electronic component mounted on the component mounting surface is a prepreg. The step of laminating the prepreg on the core layer and the laminated body of the core layer and the prepreg are pressurized in the laminating direction in the reduced pressure atmosphere, and secondly heated to form a cured prepreg. Ri together to seal the electronic component, comprising a step of further advancing the curing of the thermosetting resin, a method of manufacturing an electronic component module.

Description

  The present invention provides an electronic component module comprising a core layer having a component mounting surface on which a metal foil wiring pattern is formed, an electronic component mounted on the component mounting surface, and a resin layer for sealing the electronic component. It relates to a manufacturing method.

  Many electronic components such as semiconductor elements are incorporated in electronic devices in the form of electronic component modules. An electronic component module is generally formed by mounting an electronic component on a substrate on which a metal foil wiring pattern is formed, and then sealing the electronic component with a resin layer. While higher mounting density of electronic component modules is required, an electronic component module in which a plurality of wiring patterns are stacked and electronic components are mounted on an inner layer wiring pattern has been used (for example, Patent Document 1). Such an electronic component module is also referred to as a component built-in substrate.

  In Patent Document 1, first, after mounting an electronic component on the land of the wiring pattern of the inner layer substrate (core layer), the joint between the terminal of the electronic component and the land is covered with a chemical-resistant resin, A wiring pattern roughening process (blackening process) is performed. And an electronic component is enclosed with a prepreg, a copper foil is arrange | positioned so that a core layer may be opposed via a prepreg, and a laminated body is formed. By pressing the laminated body in the laminating direction and heating the laminated body, a laminated board containing components is formed. Thereafter, by processing the copper foil, a further wiring pattern is formed, and a via for connecting the wiring patterns is further formed. By performing such an operation as many times as necessary, the component-embedded substrate is completed.

  The core layer can be obtained by attaching a metal foil such as a copper foil to a thin resin substrate and then patterning the metal foil. The metal foil provides a wiring pattern in the inner layer of the component-embedded substrate and has a role of supplementing the rigidity of the thin and flexible resin substrate. On the other hand, the prepreg is made of a fiber sheet impregnated with a semi-cured thermosetting resin, and further curing of the thermosetting resin proceeds by heating. As a result, the electronic component and the inner layer wiring pattern are sealed with the cured resin.

  In order to obtain a good sealing state, it is necessary to make the prepreg adhere to the metal foil. However, the thermosetting resin constituting the prepreg has poor adhesion to the surface of the metal foil forming the wiring pattern. Therefore, in order to improve the adhesion between the thermosetting resin and the wiring pattern, the surface of the metal foil is roughened. Prior to the lamination of the prepreg and the wiring pattern, the surface of the metal foil or the wiring pattern is roughened to form a fine anchor pattern, thereby improving the adhesion with the thermosetting resin. As the roughening treatment, a wet treatment is generally used in which the core layer is immersed in a treatment solution having a function of chemically eroding the surface of the metal foil.

JP 2004-311736 A

  If the roughening process of metal foil is performed for the core layer in which the electronic component was mounted like patent document 1, the effect | action of a roughening process may act also on a junction part. In particular, the toe portion of the fillet formed at the joint is susceptible to erosion. When micro cracks are formed at the toe due to such erosion, the joint is easily broken. In Patent Document 1, before the roughening treatment, the joint portion is covered with a thermosetting resin, and the resin is cured by heating to protect the joint portion. However, when the resin is not sufficiently cured, A similar problem arises. On the other hand, in order to sufficiently advance the curing of the resin that covers the joint portion, it is necessary to set the heating time longer, which impedes the productivity of the electronic component module.

  It has also been proposed to use solder particles dispersed in a thermosetting resin as a bonding material for bonding terminals and lands of an electronic component. In this case, the solder joint can be covered with the cured product of the thermosetting resin simultaneously with the mounting of the electronic component on the core layer by reflow. However, in the reflow process, it is difficult to sufficiently cure the thermosetting resin, and the joint is likely to be in a state of being covered with a semi-cured thermosetting resin. Therefore, reheating (after-cure) is required to further advance the curing, which also hinders the productivity of the electronic component module.

  In addition, when the solder joint is covered with a cured thermosetting resin simultaneously with the mounting of the electronic component, voids are likely to occur between the electronic component and the core layer. If after-curing is performed with the voids generated, the voids are surrounded by the cured resin, and the voids cannot be removed in subsequent steps. As a result, if the solder is remelted during reflow, the solder flows into the void, resulting in poor bonding.

  As described above, in the conventional method, it is difficult to efficiently produce a highly reliable electronic component module.

The present invention provides a step of preparing a core layer having a component mounting surface on which a first wiring pattern including lands for connecting electronic components is formed;
Roughening the surface of the first wiring pattern;
Disposing a bonding material including a thermosetting resin and solder particles dispersed in the thermosetting resin on at least a portion covering the land of the first wiring pattern after the roughening;
Preparing an electronic component having a terminal, landing the terminal on the land via the bonding material, and mounting the electronic component on the component mounting surface;
First heating the core layer on which the electronic component is mounted, joining the terminal to the land with the solder, and semi-curing the thermosetting resin;
Laminating the prepreg on the core layer so that the electronic component mounted on the component mounting surface is surrounded by the prepreg;
In a reduced pressure atmosphere, the laminate of the core layer and the prepreg is pressurized in the laminating direction and second heated to seal the electronic component with a cured product of the prepreg and the thermosetting And a step of further proceeding the curing of the resin.

According to the present invention, since the electronic component is mounted on the core layer after the surface of the wiring pattern on the component mounting surface is roughened, it is possible to prevent the occurrence of micro cracks in the solder joint during the roughening process. it can. Moreover, since the thermosetting resin which coat | covers the solder joint part after reflow is a semi-hardened state, when heating the laminated body of a core layer and a prepreg, it will be in the state which can be softened and flowed. Therefore, even when a void is generated between the electronic component and the core layer, if the laminate is pressurized in a reduced-pressure atmosphere, the void moves through the semi-cured thermosetting resin and is released to the outside. Is done. In addition, it is not necessary to completely cure the thermosetting resin that covers the solder joint portion during reflow, and it is not necessary to perform after-curing after reflow, so that the productivity of the electronic component module is improved.
While the novel features of the invention are set forth in the appended claims, the invention will be better understood by reference to the following detailed description, taken in conjunction with the other objects and features of the present application, both in terms of construction and content. Will be understood.

It is explanatory drawing which shows the process ((A)-(C)) until it arrange | positions a joining material to the component mounting surface of a core layer among the manufacturing processes of the electronic component module which concerns on one Embodiment of this invention. Among the manufacturing steps of the electronic component module according to the embodiment of the present invention, the steps ((D) to (F)) from the mounting of the electronic component on the component mounting surface through the bonding material to the placement of the prepreg are performed. It is explanatory drawing shown. It is explanatory drawing which shows the process ((G)-(I)) until it completes a component built-in board | substrate from the laminated body of a core layer and a prepreg among the manufacturing processes of the electronic component module which concerns on one Embodiment of this invention. .

First, the structure of the electronic component module will be described.
An electronic component module manufactured by the manufacturing method of the present invention includes a core layer having a component mounting surface on which a metal foil wiring pattern is formed, an electronic component mounted on the component mounting surface, and a resin that seals the electronic component A layer. In particular, an electronic component module called a component-embedded substrate has a structure in which a plurality of wiring patterns (metal foils) are stacked around a core layer serving as a base. Between the adjacent wiring patterns, a cured resin layer obtained by thermally curing the prepreg is disposed. The resin layer has a function of bonding wiring patterns adjacent to each other. Since an electronic component such as a chip component is mounted on the wiring pattern of the core layer, the resin layer also has a function of sealing the electronic component. In general, solder is used for connection between the terminal of the electronic component and the land of the wiring pattern. Therefore, when manufacturing the electronic component module, heating for mounting the electronic component on the wiring pattern and heating for bonding the wiring patterns together are repeated.

  The core layer has a thin resin substrate, and a wiring pattern (first wiring pattern) is formed on one or both surfaces thereof. The shape of the wiring pattern varies, and the portion connected to the terminal of the electronic component is called a land. Such a core layer is formed by attaching a metal foil such as a copper foil to a resin substrate and then patterning the metal foil.

Next, the manufacturing method of the electronic component module of this invention is demonstrated.
The manufacturing method includes: (a) preparing a core layer having a component mounting surface on which a first wiring pattern including lands for connecting electronic components is formed; and (b) roughening the surface of the first wiring pattern. And (c) a bonding material including a thermosetting resin and solder particles dispersed in the thermosetting resin is disposed on at least a portion covering the land of the first wiring pattern after the roughening. (D) preparing an electronic component having a terminal, landing the terminal on the land via the bonding material, and mounting the electronic component on the component mounting surface; A step of first heating the core layer on which the electronic component is mounted, joining the terminal to the land with the solder, and semi-curing the thermosetting resin; and (f) mounted on the component mounting surface. The electronic component A step of laminating the prepreg on the core layer so as to be surrounded by, and (g) pressurizing the laminated body of the core layer and the prepreg in a laminating direction in a reduced pressure atmosphere and second heating. The step of sealing the electronic component with the cured product of the prepreg and further curing of the thermosetting resin is included.

  In addition, before pressurizing the said laminated body and carrying out 2nd heating, you may arrange | position metal foil, such as copper foil, so that a core layer may be opposed via a prepreg. In this case, after the second heating, the second wiring pattern can be formed by forming vias for connecting the wiring patterns (h) or patterning (i) the metal foil. By repeating the same operation, it is possible to obtain a component-embedded substrate having a high mounting density in which a plurality of wiring patterns are stacked.

Hereafter, each process is demonstrated in detail, referring drawings.
1-3 is explanatory drawing which shows the process of the manufacturing method of the electronic component module which concerns on one Embodiment of this invention.

First, a core layer (base wiring layer) having a component mounting surface on which a first wiring pattern including lands for connecting electronic components is formed is prepared (step (a)).
In FIG. 1A, the core layer 1 includes an insulating resin substrate 2, a first wiring pattern 3 disposed on the upper surface 2a of the resin substrate 2, and a wiring pattern 4 disposed on the lower surface 2b of the resin substrate 2. It consists of and. Each wiring pattern is formed of a metal foil such as a copper foil or a metal thin film. The upper surface of the core layer 1 is a component mounting surface, and a part of the first wiring pattern 3 is a land 3a for connecting terminals of electronic components. On the land 3a, for example, a chip-type small electronic component in which connection terminals are formed at both ends, such as resistors and capacitors, and an electronic component including a semiconductor in which metal bumps to be connection terminals are formed on the lower surface are mounted. The

  Note that the wiring patterns 3 and 4 include not only a part that actually functions as a wiring circuit but also a part that remains on the surface of the core layer 1 after patterning and does not have a function as a wiring circuit.

Next, the surface of the wiring patterns 3 and 4 is roughened (step (b)).
The roughening treatment is performed in a later step in order to improve the adhesion between the prepreg and each wiring pattern. By the roughening treatment, fine irregularities are formed on the surface of each wiring pattern, and the adhesion between the thermosetting resin contained in the prepreg and the wiring pattern is improved. The method of the roughening treatment is not particularly limited, but can be performed by immersing the core layer in a treatment solution (strongly acidic solution or strongly alkaline solution) having an action of chemically eroding the metal surface. Since the surfaces 3b and 4b of the wiring pattern roughened by the treatment liquid change to black or a color close thereto, the roughening treatment is also referred to as blackening treatment (see FIG. 1B). Note that as a roughening treatment method, plasma treatment or the like may be performed in addition to the wet blackening treatment using a treatment liquid.

  As described above, a problem occurs when the roughening process is performed after the electronic component is mounted on the core layer 1 by performing the roughening process of the wiring pattern in a state where the electronic component is not mounted on the core layer 1. Can be avoided. That is, it is possible to avoid the surface of the joint (solder joint) between the terminal of the electronic component and the land of the wiring pattern from being eroded by the processing liquid. Therefore, defects such as microcracks in the solder joint are less likely to occur.

Next, as shown in FIG. 1C, a bonding material including a thermosetting resin and solder particles dispersed in the thermosetting resin is disposed on at least a portion covering the land 3a of the roughened wiring pattern. (Step (c)).
Examples of the method of arranging the bonding material 6 on the surface of the core layer 1 include a screen printing method, a method of applying with a dispenser, and a method of pasting a bonding material previously formed into a film shape onto a component mounting surface. However, various methods can be selected according to the shape and range of the part where the bonding material 6 is disposed.

  The bonding material 6 is disposed at least in a portion covering the land 3a. However, the bonding material 6 may be disposed so that not only the surface of the land 3a but also the first wiring pattern 3 is entirely covered. For example, the bonding material 6 may be disposed over the entire area where the first wiring pattern 3 is formed on the upper surface of the resin substrate 2. In this case, a method of sticking the bonding material 6 formed in a film shape to the component mounting surface is convenient.

  As the bonding material 6 including the thermosetting resin and the solder particles dispersed in the thermosetting resin, a so-called thermosetting cream solder can be used. The thermosetting resin contained in the bonding material 6 preferably includes a component having an active action of removing the oxide film on the surface of the solder particles. Examples of the component having such an active action include components used for flux such as organic acids and hydrohalides. As the main component of the thermosetting resin, epoxy resin, acrylate resin, polyimide, polyurethane, phenol resin, unsaturated polyester resin, or the like is used. The thermosetting resin may contain a curing agent, a curing accelerator, and the like. As the curing agent, an acid anhydride, an aliphatic or aromatic amine, imidazole or a derivative thereof is preferably used, and examples of the curing accelerator include dicyandiamide. The composition of the thermosetting resin is designed according to the temperature of the first heating at the time of soldering and the time of the first heating so as to be in a semi-cured state after mounting the electronic component on the core layer 1.

  Although it does not specifically limit as a solder particle, In the heating process for bonding the prepreg performed later to the core layer 1, it is preferable to have a composition which does not melt. For example, a solder having a melting point of about 220 ° C. can be used like an Sn—Ag—Cu alloy. However, the present invention is not limited thereto, and for example, a low melting point solder such as a Sn—Bi alloy can be used.

  Next, an electronic component 7 having a terminal 7a is prepared. As shown in FIG. 2D, the terminal 7a is landed on the land 3a through the bonding material 6, and the electronic component 7 is mounted on the component mounting surface. (Step (d)). In FIG. 2D, a chip component is mounted as the electronic component 7, but the present invention is not limited to this.

  Various electronic component mounting apparatuses can be used for mounting the electronic component 7. Generally, an electronic component mounting apparatus has a mounting head provided with a suction nozzle, and the mounting head can freely move in a three-dimensional direction. The electronic component 7 is supplied to the component supply unit of the electronic component mounting apparatus by a tape feeder or the like. In the component supply unit, the mounting head picks up the electronic component 7 and moves it above the component mounting surface of the core layer 1. Then, the alignment between the terminal 7b of the electronic component 7 and the land 3a of the first wiring pattern 3 is automatically performed. Subsequently, the electronic component 7 is mounted so that the terminal 7b is landed on the land 3a via the bonding material 6.

  Thereby, the electronic component 7 is held by the base wiring layer 1 via the adhesive bonding material 6. At this time, as shown in FIG. 2D, a gap 17 may be formed between the upper surface of the core layer 1 and the lower surface of the electronic component 7.

  Next, the core layer 1 on which the electronic component 7 is mounted is heated (first heating), and the terminal 7a of the electronic component 7 is bonded to the land 3a by solder contained in the bonding material 6. At that time, the thermosetting resin contained in the bonding material 6 is cured until it becomes a semi-cured state (step (d)).

  In the first heating, it is necessary to reflow the solder particles contained in the bonding material 6 and it is necessary to heat at a temperature higher than the melting point of the solder. By the first heating, the solder particles are melted and the viscosity of the thermosetting resin is lowered. The molten solder flows in the thermosetting resin having a reduced viscosity, moves between the terminal 7a of the electronic component 7 and the land 3a, and spreads wet on the surfaces of the terminal 7a and the land 3a. Thereafter, when cooled, the solder is solidified, and a fillet-like solder joint 6x is formed between the terminal 7a of the electronic component 7 and the land 3a of the wiring pattern 3 as shown in FIG. On the other hand, the thermosetting resin is in a semi-cured state and is filled in the gap between the electronic component 7 and the core layer 1, and a part thereof covers the solder joint portion 6 x to form the resin reinforcing portion 6 y. To do. The resin reinforcing portion 6y serves to protect the solder joint portion 6x and reinforce the joining of the electronic component 7 to the core layer 1 by the solder joint portion 6x.

  Although the curing reaction of the thermosetting resin progresses gradually, the melting and solidification of the solder proceeds rapidly, so that when the solder joint 6x is formed, the thermosetting resin cannot be brought into a semi-cured state. Easy. Here, the semi-cured state refers to, for example, a state in which the curing reaction rate of the thermosetting resin is 10 to 70%. The curing reaction rate is measured by a differential scanning calorimeter (DSC) for the heat amounts of the thermosetting resin before the first heating and the semi-cured thermosetting resin cooled to room temperature after the first heating. Therefore, it can be obtained by the following method.

  When the heat quantity of the thermosetting resin before being subjected to the first heating is Q1, and the heat quantity of the thermosetting resin in the semi-cured state after the first heating is Q2, the difference between Q1 and Q2 (Q1-Q2) is Corresponds to the amount of heat of the cured curing reaction. Therefore, a value indicating the ratio R (R = (Q1-Q2) / Q1) obtained by dividing this difference by the heat quantity Q1 is a curing reaction rate. When the curing reaction of the thermosetting resin has hardly progressed, Q1 and Q2 are substantially equal, and the curing reaction rate is 0%. On the other hand, after the curing reaction has completely progressed, Q2 becomes 0, so that the curing reaction rate becomes 100%. The degree of progress of the curing reaction of the thermosetting resin depends on the type and amount of the curing agent blended in the thermosetting resin, the heating condition profile, and the like.

  Even if the semi-cured thermosetting resin is in a molten state or a flexible state before cooling, it becomes a solid having no fluidity when cooled to room temperature, and functions as a resin reinforcing portion 6y. . Therefore, if the gap 17 is formed between the upper surface of the core layer 1 and the lower surface of the electronic component 7 before the first heating, the gap 17 causes the gap to be surrounded by the resin reinforcing portion 6y. The void 8 in the state is easily formed. However, such a void 8 is discharged to the outside in a later process.

  By forming the resin reinforcing portion 6y, the solder joint portion 6x that holds the electronic component 7 on the core layer 1 is protected, and the holding force of the electronic component 7 by the solder joint portion 6x is reinforced. Further, since the resin reinforcing portion 6y is melted and mixed with the prepreg and integrated in the subsequent process, the electronic component 7 and the solder joint portion 6x can be more reliably sealed. In other words, the resin reinforcing portion 6y finally serves to seal between the electronic component 7 and the core layer 1.

  Next, as shown in FIG. 2F, a prepreg 9 is laminated on the core layer 1 so as to surround the electronic component 7 mounted on the component mounting surface (step (f)).

  When the prepregs 9 are stacked and arranged, it is desirable that the prepregs 9 be arranged so that no gap is generated between the electronic component 7 and the prepreg 9 as much as possible. The prepreg 9 is desirably arranged so that not only the electronic component 7 but also the first wiring pattern 3 is entirely sealed.

  In FIG. 2F, a prepreg 9 having an opening 9a corresponding to the electronic component 7 is disposed so as to be in close contact with the upper surface of the resin substrate 2 and the electronic component 7 and to surround the electronic component 7. Further, a pair of prepregs 10a and 10b are arranged so as to sandwich the core layer 1 from both sides, and metal foils 11a and 11b are respectively attached to the surfaces of the prepregs 10a and 10b opposite to the core layer 1 side. It has been. By setting it as such a structure, both surfaces of the core layer 1 can be completely sealed with the resin layer derived from a prepreg. In a later step, a desired wiring pattern can be formed on each metal foil 11.

  Next, the laminated body of the core layer 1 and the prepregs 9, 10a, and 10b is pressurized in the laminating direction and heated (second heating) in a reduced pressure atmosphere. Thereby, the electronic component 7 is sealed by the prepregs 9 and 10a, and the curing of the semi-cured resin reinforcing portion 6y derived from the bonding material 6 further proceeds (step (g)). The pressure of the reduced pressure atmosphere may be, for example, 13.3 kPa (100 Torr) or less.

The laminated body may be heated with a general press device at a pressure of about 30 kgf / cm ² , for example. At this time, the temperature of the second heating may be a temperature at which the curing reaction of the thermosetting resin contained in the prepreg and the curing reaction of the resin reinforcing portion 6y proceed. However, it is preferable to set the temperature below the melting temperature of the solder so that the solder joint 6x is not displaced. For example, when the melting point of the solder is about 220 ° C., the temperature of the second heating can be about 150 to 200 ° C.

As shown in FIG. 3G, the second heating softens the thermosetting resin included in the prepregs 9 and 10a and the thermosetting resin constituting the resin reinforcing portion 6y, so that the contact interfaces melt together. The parts-embedded substrate 14 is formed by wearing and integrating. At this time, the first wiring pattern 3 and the electronic component 7 are in close contact with the adjacent prepreg. Then, the curing reaction of the thermosetting resin included in the prepregs 9 and 10a and the thermosetting resin constituting the resin reinforcing portion 6y proceeds, and the resin layer 12 is formed. In FIG. 3G, the interface between the resin layer portion derived from the resin reinforcing portion 6y and the resin layer portion derived from the prepreg is indicated by a broken line.
Similarly, the prepreg 10 b adjacent to the wiring pattern 4 on the lower surface of the core layer 1 forms a resin layer 13 in close contact with the wiring pattern 4.

  Since fine irregularities are formed on the surfaces of the wiring patterns 3 and 4 by the roughening treatment, good adhesion between the wiring patterns 3 and 4 and the resin layer 12 is achieved. Further, when there is a void 8 surrounded by the resin reinforcing portion 6y between the electronic component 7 and the core layer 1, the void 8 is caused by the pressure applied in the stacking direction and the effect of the reduced-pressure atmosphere. Is pushed out. Accordingly, it is possible to prevent a bonding failure or the like derived from voids.

  That is, in the step (g), not only the wiring patterns 3, 4 and the electronic component 7 are sealed with the prepregs 9, 10 a, 10 b, but also the semi-cured resin reinforcing portion 6 y is flowed to Voids can be removed. Thereby, the sealing of a more favorable state is realizable. And since the curing of the semi-cured resin reinforcing portion 6y and the curing of the thermosetting resin contained in the prepregs 9, 10a, and 10b are performed in the same process, it becomes possible to omit after-cure, The productivity of component modules is also increased.

  Next, as shown in FIG. 3H, via holes are formed in the obtained component-embedded substrate 14 in the thickness direction, and a plated layer 15 is formed on the inner surface of the holes. Thereby, the interlayer wiring which connects the 1st wiring pattern 3 of the core layer 1 and the metal foil 11a, 11b arrange | positioned at both surfaces of the board | substrate 14, respectively is formed.

  For example, a conformal method can be used for forming the via hole. First, only the metal foil present on the surface of the via hole forming portion is removed by etching by photolithography or the like. Next, when the portion where the metal foil is removed is irradiated with a laser, the remaining surrounding metal foil becomes a conformal mask, and a via hole can be formed in the portion where the metal foil is removed. For the laser processing, a carbon dioxide laser, a YAG laser, or the like can be used.

  Next, since smear (resin residue) is generated in laser processing, desmear processing in the via hole is performed. As the chemical for desmear treatment, for example, an oxidizing agent aqueous solution or the like can be used. Specifically, an alkaline aqueous solution of potassium permanganate or sodium permanganate, an aqueous sulfuric acid solution of chromic acid or sodium dichromate, or the like can be used. Prior to treatment with these chemicals, pretreatment in the via hole may be performed using an alkali swelling liquid.

  After the desmear process, after neutralizing with a predetermined neutralizing solution, a plating layer 15 is formed on the inner surface of the desmeared via hole, and a conduction process is performed. At this time, treatment by a dry method such as vapor deposition, sputtering, or ion plating may be performed, but treatment by a wet method such as electroless plating or electrolytic plating is preferable in consideration of mass productivity.

  Thereafter, as shown in FIG. 3I, the second wiring pattern is formed by patterning one of the metal foils 11a. Naturally, the other metal foil 11b may be patterned, and in this case, a third wiring pattern is formed. The second and third wiring patterns formed in this way are further targets for mounting electronic components. By repeating the same operation further, an electronic component module having a high mounting density in which more wiring patterns are stacked can be obtained.

The present invention relates to an electronic component module comprising a core layer having a component mounting surface on which a metal foil wiring pattern is formed, an electronic component mounted on the component mounting surface, and a resin layer for sealing the electronic component. However, it is useful in the field of manufacturing a component built-in board in which a plurality of wiring patterns are laminated.
While this invention has been described in terms of the presently preferred embodiments, such disclosure should not be construed as limiting. Various changes and modifications will no doubt become apparent to those skilled in the art to which the present invention pertains after reading the above disclosure. Accordingly, the appended claims should be construed to include all variations and modifications without departing from the true spirit and scope of this invention.

Claims (6)

Preparing a core layer having a component mounting surface on which a first wiring pattern including lands for connecting electronic components is formed;
Roughening the surface of the first wiring pattern;
Disposing a bonding material including a thermosetting resin and solder particles dispersed in the thermosetting resin on at least a portion covering the land of the first wiring pattern after the roughening;
Preparing an electronic component having a terminal, landing the terminal on the land via the bonding material, and mounting the electronic component on the component mounting surface;
First heating the core layer on which the electronic component is mounted, joining the terminal to the land with the solder, and semi-curing the thermosetting resin;
Laminating the prepreg on the core layer so that the electronic component mounted on the component mounting surface is surrounded by the prepreg;
In a reduced pressure atmosphere, the laminate of the core layer and the prepreg is pressurized in the laminating direction and second heated to seal the electronic component with a cured product of the prepreg and the thermosetting A step of further curing the resin, and a method for producing an electronic component module.   The method for manufacturing an electronic component module according to claim 1, wherein a curing reaction rate of the thermosetting resin by the first heating is 10 to 70%.   3. The method of manufacturing an electronic component module according to claim 1, wherein a temperature of the second heating is lower than a melting temperature of the solder.   4. The method of manufacturing an electronic component module according to claim 1, wherein the bonding material is arranged on the component mounting surface so that at least the entire first wiring pattern is covered. 5.   The metal foil is disposed so as to face the core layer via the prepreg, and then the laminated body is pressurized in the laminating direction and secondly heated. The manufacturing method of the electronic component module of description.   The method for manufacturing an electronic component module according to claim 1, wherein after sealing the electronic component with a cured product of the prepreg, the metal foil is patterned to form a second wiring pattern. .

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