JP2008159973A - Electronic component module and circuit board with built-in components incorporating the module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To incorporate an electronic component with a terminal, having an ultrafine pitch of 200 μm or smaller, and to prevent damages due to thermal stress at reflow process, in the electronic component of an electronic component module incorporated in a circuit board. <P>SOLUTION: Singular or a plurality of electronic components 14 are mounted on a first resin layer 11. A second resin layer 12 made of a material, having low elastic modulus and low thermal expansion coefficient on the first resin layer 11 so as to surround a periphery of the electronic component 14 and not to cover a surface of a terminal electrode 14a of the electronic component 14. A photosensitive third resin layer 13 covers the second resin layer 12 and the electronic component 14; a via hole 13a is formed in the third resin layer 13 by photolithographic method; and an electrode pad 15 led out from the terminal electrode 14a of the electronic component via the via hole is provided on the third resin layer 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electronic component module and a circuit board with a built-in component, and more particularly to an electronic component module having an electronic component embedded in a resin layer and a circuit board with the electronic component module built-in.

In electronic devices, the number of electronic components to be mounted on a board is steadily increasing as the functions become multifunctional and sophisticated. For example, in portable devices, previously only a single frequency was used for communication, but in recent years it has come to use multiple frequency bands, and this requires a plurality of radio circuits and antennas. Accordingly, the number of electronic components used increases. On the other hand, since the area of the board on which the electronic component is mounted is limited, if the number of electronic parts to be used continues to increase, a situation where the board cannot be mounted on the board occurs. In response to such problems, attempts have recently been made to incorporate some of the increasing number of electronic components inside the electronic circuit board. So-called component built-in.
The method of incorporating components can be broadly classified into the following two types.
1) Embedding electronic components 2) Making thick film elements 1) Technology for incorporating existing electronic components directly into an electronic circuit board 2) Functional elements consisting of thick or thin films during the manufacturing process of electronic circuit boards This is a method of forming and then incorporating a functional element by a build-up process. Since 1) has a great advantage that an electronic component having characteristics already realized can be incorporated as it is, many techniques have been studied and disclosed in recent years.

For example, Patent Document 1 includes a core member, a resin layer covering the core member, and a bottomless hole formed in the core member so as to penetrate the front and back of the core member, and an electronic component is mounted in the bottomless hole In other words, a composite multilayer substrate is disclosed in which an exposed portion that is not covered with the resin is provided on the surface (end surface) except for the front and back surfaces of the core member. It is also described that the core member is particularly characterized by being a metal. A small hole is opened in the resin layer covering the core member by a laser beam, and interlayer connection is performed through the small hole. The composite multilayer described in Patent Document 1 has a feature that the transfer loss of a high-frequency signal can be reduced by using the exposed portion of the metal core as a terminal.
Patent Document 2 discloses a printed circuit board in which an electrical element is disposed in a thermoplastic resin, and an electrode of the electrical element is electrically connected to a conductor pattern through a connection via hole filled with a connection material. The thermoplastic resin is formed by laminating a plurality of resin plates and bonding them to each other by pressing and heating from the upper and lower surfaces, and the upper surface and the lower surface of the electric element in the stacking direction are provided with the pressurization. The connection including at least the connection via hole at a position that regulates the inclination in the stacking direction of the electric element, the buckling of the connection via hole filled with the connection material, and the tilt in the stacking direction of the conductor pattern during heating. A printed circuit board is described that faces a plurality of via holes filled with material. According to this method, since the via hole filled with the connecting material is added so as to reduce or eliminate the stress in the rotation direction of the electric element, buckling and inclination of the conductor pattern are less likely to occur. Connection reliability between is improved. The connection via hole is formed by forming a via hole by irradiating a resin film with a laser beam, drilling or punching, and filling it with a conductive paste.
In Patent Document 3, a plurality of substrates on which semiconductor elements are flip-chip mounted are stacked and the substrates are electrically connected, and the plurality of substrates are thermally cured such as epoxy or phenolic resin including at least a thermosetting resin. It is bonded with a curable resin composition and is electrically connected through an inner via provided in the thermosetting resin composition, and is lower than the thermosetting resin composition on the surface opposite to the mounting surface of the semiconductor element. Disclosed is a semiconductor device in which a low-elastic material that is an elastic modulus is in close contact, the low-elastic material is in close contact with a substrate facing the semiconductor element, and the semiconductor element is embedded inside the substrate. ing. The inner via is formed by irradiating the thermosetting resin composition with a laser beam or punching to form a through hole and filling with a conductive paste. According to this technology, since the thermosetting resin composition is laminated and integrated after sealing the semiconductor element with the low elastic modulus resin, the voids in the electronic circuit board can be reduced and the thermosetting resin composition can be reduced. It becomes possible to reduce the thermal deformation of the electronic circuit board when the objects are integrated.
Furthermore, Patent Document 4 describes a printed wiring board using a photosensitive film having fluidity capable of embedding pattern circuit irregularities. This photosensitive film has a thickness of 1 to 60 μm, and even if it covers a pattern circuit having a thickness of 50 to 95% of the thickness, the height difference of the unevenness formed on the surface opposite to the embedded side is 5 μm or less. It is said that there is.
JP 2004-146419 A JP 2006-121005 A JP 2006-120935 A JP 2004-143300 A

Thus, conventionally, a via hole is directly drilled from the surface of the core substrate containing the electronic component to the terminal electrode of the electronic component with a laser, and the terminal of the electronic component is drawn out to the core substrate surface through the via hole. From the surface of the electronic circuit board through a normal build-up process, or via holes are formed in the built-in electronic components directly from the surface of the electronic circuit board and connected to the surface wiring. However, when opening with a laser beam, the via hole diameter is the smallest, about φ50 μm, and the land diameter needs to be at least about 75 μm. Therefore, it is difficult to incorporate electronic components having terminal electrodes with a pitch of 200 μm or less. is there.
In addition, when the core substrate is made of a highly rigid metal so that the electronic components are not damaged, the density of the core substrate is higher than that of the resin core layer of the same volume. Increases can be a problem. On the other hand, if the elastic modulus of the build-up resin for embedding electronic components is lowered for the purpose of reducing the stress and thermal stress applied to the substrate in the process of embedding the electronic components, there is concern about the strength of the entire electronic circuit board. Remains.
An object of the present invention is to solve the above-mentioned problems of the prior art. The purpose of the present invention is, firstly, an electronic component having terminals with an ultrafine pitch of 200 μm or less and a pad on the surface of an electronic circuit board. The second objective is to provide an electronic component module that can be connected with as little inductance as possible. Second, while maintaining the strength of the circuit board sufficiently high, the electronic components incorporated therein are used during the reflow process. Is not damaged by the thermal stress applied to the surface.

  In order to achieve the above object, according to the present invention, one or a plurality of electronic components are mounted on a first resin layer, and the electronic components are formed on a second resin layer formed on the first resin layer. The electronic component is housed in a resin layer, and the electronic component and the second resin layer are covered with a third resin layer, and terminals of the electronic component are opened in the third resin layer. An electronic component module connected to a pad formed on the third resin layer through a via hole, wherein the third resin layer is formed of a photosensitive resin, Is provided.

  In order to achieve the above object, according to the present invention, one or more electronic components are mounted on the first resin layer, and the electronic components are formed on the first resin layer. 2 and is covered with a third resin layer on the electronic component and the second resin layer, and terminals of the electronic component are opened in the third resin layer. In the electronic component module connected to the pad formed on the third resin layer through the formed via hole, the Young's modulus (GPa) and heat of the resin material constituting the second resin layer at 25 ° C. The product of the expansion coefficient (ppm / K) is 300 or less, the third resin layer is formed of a photosensitive resin, and the via hole is formed in the third resin layer by a photolithography method. Electronic component Lumpur, is provided.

In the electronic component module of the present invention, one or a plurality of electronic components are mounted on a flat substrate, the surface other than the surface of the electronic component is covered with a resin, and the surface of the electronic component and the surface of the resin are covered with a photosensitive resin. Even if the pitch of the terminal electrode of the electronic component is 200 μm or less that cannot be connected by a via hole formed by a laser beam by opening a via hole using a photolithography method to form a conductive pattern, It is possible to extend the terminal interval (pad interval) by drawing the terminal electrode to the surface of the photosensitive resin. Even if the terminal electrode is incorporated in the electronic circuit board, the terminal electrode is connected to the surface of the electronic circuit board through a via hole opened by a laser beam. It can be expanded to a pitch that can be pulled out. As a result, a plurality of terminal electrodes can be formed on a silicon substrate by a thin film process or an array element in which a plurality of terminal electrodes are formed at a narrow pitch on a single component, and an integrated passive element having a terminal electrode with an ultrafine pitch. However, it can be built in the electronic circuit board. In addition, by making a large number of passive components into one module, it is possible to significantly reduce the number of man-hours when incorporating them in an electronic circuit board.
In addition, by reducing the product of the elastic modulus and thermal expansion coefficient of the resin that covers the electronic component to a certain value or less, the thermal stress applied to the built-in electronic component is reduced by the reflow process for mounting another electronic component on the circuit board. A highly reliable electronic component module can be provided. Also, the resin that covers the electronic component is not the same as the resin that constitutes the circuit board with the built-in component. A circuit board with a built-in component having high resistance can be provided. In other words, by using a resin containing a filler in the core layer or build-up layer of the component built-in circuit board containing the electronic component module, the overall strength of the component built-in board can be maintained while reducing the stress applied to the electronic component. Can be made sufficiently high.

  According to the present invention, when applied to a passive component as an electronic component, the following effects can also be expected. While active components such as LSI can be mounted on the first resin layer from 1 to at most 2-3, passive components such as LCR can be mounted in units of several tens. is assumed. In that case, in addition to the above-described effects, it is possible to greatly reduce the labor of mounting the components in the component-embedding process by making many components into one module.

(First embodiment)
FIG. 1 is a cross-sectional view showing a first embodiment of an electronic component module of the present invention. As shown in FIG. 1, in the electronic component module 10 of the present embodiment, a surface-mount type electronic component 14 is mounted on a first resin layer 11 having a flat surface, and is fixed by an adhesive resin. Although there is no restriction | limiting in particular in the thickness of the 1st resin layer 11, When considering the case where the electronic component module 10 of this invention is incorporated in a circuit board, it is desirable that it is about 20 micrometers-50 micrometers in thickness. The electronic component 14 is the smallest, currently available, 0402 size (0.4 mm × 0.2 mm × 0.2 mm). There is no particular upper limit for the thicker one, but the size of about 3216 (3.2 mm × 1.6 mm × 1.6 mm) seems to be the limit in terms of ease of making. Therefore, it can be said that the thickness of the electronic component 14 is in the range of 0.2 mm to 1.6 mm.
All side surfaces of the electronic component 14 are covered with the second resin layer 12. Here, the surface of the second resin layer 12 and the surface of the electronic component 14 have the same height, and the upper surface of the electronic component 14 is not covered with the second resin layer 12. Further, a photosensitive third resin layer 13 is formed on the second resin layer 12 and the electronic component 14.
The preferred physical property value for the second resin layer was set to a range in which the product of Young's modulus (GPa) and thermal expansion coefficient (ppm / K) at 25 ° C. was approximately 300 or less for the following reasons. The internal stress σ (MPa) applied to the built-in electronic components is α (ppm / K) for the thermal expansion coefficient from room temperature to around 200 ° C, E (GPa) for Young's modulus (elastic modulus), T1 for room temperature, and reflow When the temperature is T2, it can be expressed by the following formula (1).

Here, the bending strength of glass classified as the lower strength as an electronic component is used as a reference. Since the bending strength of glass is approximately 100 MPa, the internal stress is preferably about 70% or less (= about 70 MPa) of the bending strength. T1 is set to 20 ° C., and T2 is set to 260 ° C. assuming reflow when non-lead solder is used. In order to facilitate estimation of internal stress applied to the built-in electronic component, when formula (1) is simplified as formula (2), α · E = 300 ((ppm / K) · GPa) The internal stress σ applied to the built-in electronic component is 72 MPa. Therefore, such a value can be regarded as a value that is not broken by internal stress even if a thermal history of solder reflow is applied to the built-in electronic component.
A via hole 13a formed by a photolithography method is opened in the third resin layer 13, and copper is filled in the via hole 13a by a plating method. However, it is not necessary that the inside of the via hole 13a is filled with copper, and the inner wall surface of the via hole 13a may be plated. Further, the via hole 13a may be filled with a conductive paste containing metal particles such as silver.
The electronic component module of the present invention has a structure in which the terminal electrode 14a of the electronic component 14 is drawn out to the pad electrode 15 on the surface of the third resin layer 13 through the via hole 13a.

FIG. 2 is a cross-sectional view in the order of steps showing the method for manufacturing the electronic component module according to the first embodiment of the present invention. First, a copper plate 16 having a smooth surface and a surface of about 150 mm square and a thickness of 0.5 to 0.8 mm is prepared. Instead, a glass plate or a 6-inch φ silicon wafer may be used. Also, the size may be larger or smaller than this size, but it is desirable to adjust it within a range where workability is not lost.
Next, a varnish for forming the first resin layer is supplied on the copper plate 16, and the first resin layer 11 is formed through a drying and curing process after a required thickness is obtained by a spin coating method. 2 (a)]. The material for forming the first resin layer is preferably polyimide, epoxy resin, or phenol resin that can be obtained as a varnish. The reason why the spin coating method was selected is that the first resin layer can be formed flat with high accuracy. In addition to the spin coating method, a coating method such as a curtain coating method may be used. Even if it is not available as a varnish, as long as the surface is flat, a resin sheet such as a liquid crystal polymer or FR4 prepreg may be pressure-bonded onto the copper plate to form the first resin layer.
Next, the electronic component 14 having the terminal electrode 14a is mounted at a predetermined position and fixed with an adhesive [FIG. 2 (b)]. If the adhesive is thick, the flatness of the surface of the electronic component is lost. Therefore, an adhesive that can be formed as thin as possible is desirable. For example, an underfill resin is suitable. Next, a resin sheet 12a, which is previously punched with a mold or the like, is prepared at a location corresponding to the electronic component of the sheet-like resin material, and a required number of resin sheets 12a are laminated [FIG. 2 (c)]. After being laminated so as to be slightly higher than the electronic component, the second resin layer 12 is formed by thermocompression bonding. Thereafter, the second resin layer 12 is polished until the surface of the electronic component 14 is exposed, thereby matching the levels of the surfaces of the electronic component 14 and the second resin layer 12 (FIG. 2D). The resin may be removed by a method other than polishing, such as an oxygen plasma asher. In that case, the resin may be removed excessively, but unless the level difference between the surface of the electronic component and the surface of the second resin layer does not exceed 20 μm, the photosensitive resin is uniformly applied in the next step. It becomes difficult to do.

  Next, a photosensitive resin is applied onto the electronic component 14 and the second resin layer 12 by a spin coating method to form a third resin layer 13 (FIG. 2E). The thickness of the third resin layer 13 is a range that can be formed by a spin coating method, and is preferably about 1 μm to 30 μm. After the third resin layer 13 is baked, exposure and development are performed, and a via hole 13a exposing the surface of the terminal electrode 14a of the electronic component is opened in the third resin layer 13, and then cured [FIG. (F)]. Next, Ti / Cu as a plating underlayer is deposited by sputtering, a resist film having an opening in the shape of a conductive pattern to be formed by photolithography is formed, and electrolytic copper plating is performed using the resist film as a mask. The via hole is filled with copper and a pad electrode 15 is formed on the third resin layer 13. Then, the resist film is removed and the exposed plating base layer is removed by etching [FIG. 2 (g)]. The plating base layer may be formed by activation treatment and electroless plating. Alternatively, after forming a thick copper layer by electrolytic plating on the entire surface, patterning may be performed by a photoetching method to form a pad electrode. Next, the copper plate 16 is removed by etching [FIG. 2 (h)]. When glass or silicon is used for the base substrate instead of a copper plate, it cannot be removed by etching, so the upper layer is physically peeled off from the first resin layer 11. When a plurality of electronic component modules are built in the same resin layer, the resin layers 11 to 13 are cut at predetermined positions and cut into individual electronic component modules.

(Second Embodiment)
FIG. 3 is a sectional view showing a second embodiment of the electronic component module of the present invention. In FIG. 3, the same reference numerals as those in FIG. 1 showing the first embodiment are given the same reference numerals, and duplicate explanations are omitted. The electronic component module 20 of the present embodiment has the same configuration except for the electronic component module and the electronic component of the first embodiment. In the present embodiment, terminal electrodes 24a are arranged in a matrix on the surface of the electronic component 24, and a cover resin film 24b is formed on the surface of the electronic component 24 so that a part of the terminal electrode 24a is opened. ing. Here, the surface of the second resin layer 22 has the same height as the surface of the cover resin film 24 b of the electronic component 24. The terminal electrode 24a of the electronic component 24 is drawn out to the pad electrode 25 on the third resin layer 23, and the pitch is expanded to such an extent that it can be adapted to the laser beam opening.

(Third embodiment)
FIG. 4 is a cross-sectional view showing a third embodiment of the electronic component module of the present invention. In FIG. 4, the same reference numerals as those in FIG. 1 showing the first embodiment are given the same reference numerals, and duplicate explanations are omitted. The electronic component module 30 of the present embodiment is the same as the first and second embodiments except for the other components except for the electronic components. In the electronic component module 30 of the present embodiment, the electronic component 34 is a thin film multilayer integrated passive element formed on the silicon substrate 34c. Specifically, a thin film capacitor 34d is formed on the silicon substrate 34c (first layer), a thin film resistor 34e is formed on the second layer, a spiral inductor 34f is formed on the third layer, and the outermost surface (fourth layer). A terminal electrode 34a is formed on the substrate. The surface of the electronic component 34 is covered with a cover resin film 34b opened on a part of the electrode pad. The thin film capacitor 34d, the thin film resistor 34e, the spiral inductor 34f, and the terminal electrode 34a are insulated by an insulating layer 34g and are electrically connected by a micro via hole 34h formed in the insulating layer 34g.

(Fourth embodiment)
FIG. 5 is a cross-sectional view showing a fourth embodiment of the electronic component module of the present invention. In FIG. 5, the same reference numerals as those in FIG. 1 showing the first embodiment are given the same reference numerals, and duplicate explanations are omitted. The electronic component module 40 of the present embodiment is the same as the first to third embodiments except for the electronic components except for the configuration. The electronic component 44 of the present embodiment includes an aluminum foil 44a having a thickness of about 25 μm serving as a lower electrode, an aluminum oxide film 44b formed by oxidizing a necessary portion of the surface of the aluminum foil 44a by an anodic oxidation method, and aluminum being sputtered. The upper electrode 44c and the lower electrode terminal 44d formed in this manner, and a passivation film 44e formed on the element surface. The passivation film 44e opens only a part of the upper electrode 44c and the lower electrode terminal 44d. Since the total thickness of the electronic component 44 is as thin as 30 to 50 μm, there is a concern about a problem in strength. Therefore, it is desirable to use a resin containing filler for the purpose of improving the strength of the first resin layer 41.

(Fifth embodiment)
FIG. 6 shows a cross-sectional view of a component built-in circuit board in which the electronic component module 10 of the first embodiment is built. A prepreg is laminated and formed by heating and pressing, and the electronic component module 10 is mounted on the core substrate 51 and bonded and fixed. A prepreg having a perforated portion corresponding to the electronic component module 10 is laminated on the core substrate 51, and the core substrate 52 integrated with the core substrate 51 is formed by heating and pressing. After forming a via hole 52a that exposes the surface of the pad electrode 15 to the core substrate 52 by irradiating a laser beam, a conductive post filling the via hole 52a is formed by plating and a land 53 is formed on the surface of the core substrate 52. . The conductive posts filling the via holes are preferably formed of plated copper. However, after filling the via holes 52a with a conductive paste containing a metal such as silver, the conductive paste is supplied by screen printing to form the lands 53. It may be. The core substrates 51 and 52 are formed using a prepreg containing a filler in order to increase the strength of the substrate. Next, the prepreg is laminated on the upper and lower sides of the core substrate whose surfaces are integrated and metallized, and the buildup resin layer 54 is formed by heating and pressing. Thereafter, a laser beam is irradiated to open a via hole 54a in the resin layer 54, and the inner wall surface of the via hole is metallized by plating and a land 55 is formed on the surface of the resin layer 54. Finally, the through hole 56 is opened as necessary, and the inner wall surface of the through hole 56 is metallized by plating. It is desirable in terms of strength that the resin material for forming the build-up resin layer 54 also contains a filler, like the core substrates 51 and 52. The filler is often a glass cloth. The elastic modulus of the prepreg made of FR4 containing glass cloth is 20 to 30 GPa at room temperature, and the thermal expansion coefficient is about 30 ppm / K. Therefore, when applied to the product of the elastic modulus (GPa) and the thermal expansion coefficient (ppm / K) used in selecting the second resin layer described in the first embodiment, the core substrates 51, 52 and The product of the resin constituting the resin layer 54 is 600 to 900. That is, the resin constituting the core substrates 51 and 52 and the buildup resin layer 54 is inappropriate for the second resin layer. According to the circuit board with a built-in component of the present invention, the electronic component is disposed in the low elastic modulus / low thermal expansion coefficient resin, and the resin layer having the low elastic modulus / low thermal expansion coefficient is a high elastic modulus resin substrate having high mechanical strength. Is surrounded by.

  Although preferred embodiments have been described above, the present invention is not limited to these embodiments, and appropriate modifications can be made without departing from the scope of the present invention. For example, in the embodiment shown in FIG. 6, the electronic component module 10 of the first embodiment is incorporated, but instead, the electronic component modules 20 to 40 of the second to fourth embodiments are incorporated. You may make it do. In addition, the third resin layer of the electronic component module is not necessarily formed using a varnish-like material, and may be formed using a film-like resin material. Furthermore, the third resin layer does not necessarily have to be photosensitive, and a via hole may be formed in this by a photo-etching method using a non-photosensitive material. In this case, the second resin layer is allowed to slightly cover the electronic component.

Sectional drawing of the electronic component module of the 1st Embodiment of this invention. Sectional drawing of the process order which shows the manufacturing process of the electronic component module of the 1st Embodiment of this invention. Sectional drawing of the electronic component module of the 2nd Embodiment of this invention. Sectional drawing of the electronic component module of the 3rd Embodiment of this invention. Sectional drawing of the electronic component module of the 4th Embodiment of this invention. Sectional drawing of the component built-in board | substrate which incorporated the electronic component module of the 5th Embodiment of this invention.

Explanation of symbols

10, 20, 30, 40 Electronic component module 11, 21, 31, 41 First resin layer 12, 22, 32, 42 Second resin layer 12a Resin sheet 13, 23, 33, 43 Third resin layer 13a , 23a, 33a, 43a Via holes 14, 24, 34, 44 Electronic components 14a, 24a, 34a Terminal electrodes 15, 25, 35, 45 Pad electrodes 16 Copper plates 24b, 34b Cover resin films 34c Silicon substrates 34d Thin film capacitors 34e Thin film resistors 34f Spiral inductor 34g Insulating layer 34h Micro via hole 44a Aluminum foil 44b Aluminum oxide film 44c Upper electrode 44d Lower electrode terminal 44e Passivation film 51, 52 Core substrate 52a, 54a Via hole 53, 55 Land 54 Build-up resin layer 56 Through hole

Claims (13)

One or more electronic components are mounted on the first resin layer, and the electronic components are accommodated in a second resin layer formed on the first resin layer, and the electronic components and The second resin layer is covered with a third resin layer, and the terminals of the electronic component are formed on the third resin layer through via holes formed in the third resin layer. In the electronic component module connected to the pad, the third resin layer is formed of a photosensitive resin. One or more electronic components are mounted on the first resin layer, and the electronic components are accommodated in a second resin layer formed on the first resin layer, and the electronic components and The second resin layer is covered with a third resin layer, and the terminals of the electronic component are formed on the third resin layer through via holes formed in the third resin layer. In the electronic component module connected to the pad, the resin material constituting the second resin layer has a product of Young's modulus (GPa) and thermal expansion coefficient (ppm / K) at 25 ° C. of 300 or less, and The electronic component module, wherein the third resin layer is formed of a photosensitive resin, and the via hole is formed in the third resin layer by a photolithography method. The electronic component module according to claim 1, wherein the electronic component is a surface-mount type chip-type passive component. A composite passive component in which one or more passive elements are formed on a silicon substrate, a glass substrate, a ceramic substrate, or a resin substrate, or a plurality of electronic components on a silicon substrate, a glass substrate, a ceramic substrate, or a resin substrate. The electronic component module according to claim 1, wherein the passive element is an integrated passive component formed in multiple layers with an insulating layer interposed therebetween. 3. The electronic component module according to claim 1, wherein the electronic component is a passive component including one or more passive elements formed on a metal foil. 6. The electronic component module according to claim 1, wherein an inner surface of the via hole is plated with one or more kinds of metals including at least copper. The electronic component module according to claim 1, wherein the via hole is filled with a conductive paste. The electronic component module according to claim 1, wherein a thickness of the first resin layer is 50 μm or less. 9. The electronic component module according to claim 1, wherein a height difference between the surface of the second resin layer and a terminal surface of the electronic component or the passive component is within 20 μm. The electronic component module according to claim 1, wherein the photosensitive resin is epoxy, phenol epoxy, polyimide, or benzocyclobutene. 11. The electronic component module according to claim 1, wherein a pitch of terminals of the electronic component is narrower than a pitch of pads formed on the third resin layer. The electronic component module according to any one of claims 1 to 11, wherein the pad formed on the third resin layer of the electronic component module and the pad formed on the surface of the substrate are arranged in one or more steps. A circuit board with a built-in component, which is connected through via holes formed in multiple stages. 13. The component built-in circuit board according to claim 12, wherein the resin covering the electronic component module contains a filler.

Images