JP2012190887A - Electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component in which a wiring conductor of metal foil and an interlayer connection conductor can be bonded.SOLUTION: The electronic component includes: resin layers 30, 30x-30z; wiring conductors 10p-10r, 12p-12r, 14p-14r, 16p-16r, 18p-18r arranged on the principal surfaces of the resin layers 30, 30x-30z; and interlayer connection conductors 11, 13, 15, 17 penetrating the resin layers 30, 30x-30z and having both ends connected with the wiring conductors 10p-10r, 12p-12r, 14p-14r, 16p-16r, 18p-18r, respectively. In the interlayer connection conductors 11, 13, 15, 17, first and second ends 22, 22x-22z; 20, 20x-20z including both ends, respectively, in the resin layers 30, 30x-30z are formed using materials different from each other, and at least the first ends 22, 22x, 22y, 22z are connected with wiring conductors formed using metal foil.

Description

  The present invention relates to an electronic component, and more particularly to an electronic component including an interlayer connection conductor that penetrates a resin layer.

  Connects wiring conductors placed on a pair of main surfaces of a resin layer in a component-embedded board in which parts placed on a printed circuit board or ceramic board are sealed with resin, or a multilayer resin board in which resin layers are laminated Therefore, an interlayer connection conductor that penetrates the resin layer is formed. In order to meet the demand for miniaturization of the substrate and high density of the wiring, it is necessary to miniaturize the interlayer connection conductor.

  For example, FIG. 7 is an explanatory diagram of a method for producing a fine interlayer connection conductor. As shown in FIGS. 7A and 7B, a via post 113 is formed on the first wiring conductor 111 formed on the support substrate 112. Next, as shown in FIGS. 7C and 7D, the insulating paste 115 is screen-printed using the screen plate 117 having the non-ejection region 116 and the squeegee 114 so that the upper portion of the via post is exposed. An insulating layer 118 is formed. Next, as shown in FIG. 7E, a second wiring conductor 119 is formed by applying a conductive paste so as to be in contact with the via post. The via posts 113 that connect the first wiring conductor 111 and the second wiring conductor 119 are interlayer connection conductors (see, for example, Patent Document 1).

JP 2006-295116 A

  In the method of FIG. 7, the wiring conductor and the via post are formed using the conductive paste. However, when the insulating layer is a resin layer, it is conceivable to form the wiring conductor using a metal foil.

  However, if a metal foil is used for the wiring conductor in the method of FIG. 7, it is difficult to join the via post to the wiring conductor. That is, since the via post is formed by heating and curing a conductive paste screen-printed on the first wiring conductor, even if the first wiring conductor is a metal foil, the via post is bonded to the first wiring conductor. it can. However, even when the metal foil of the second wiring conductor is stacked on the cured via post, the via post only contacts the metal foil of the second wiring conductor, and there is a problem that the connectivity is unstable.

  In view of such circumstances, the present invention intends to provide an electronic component capable of joining a wiring conductor of metal foil and an interlayer connection conductor.

  In order to solve the above-described problems, the present invention provides an electronic component of a first aspect configured as follows.

  The electronic component of the first aspect includes (a) a resin layer having a pair of main surfaces facing each other, (b) a wiring conductor disposed on each of the main surfaces of the resin layer, and (c) the resin layer. In the thickness direction of the resin layer, and an interlayer connection conductor having both ends connected to the wiring conductor. The interlayer connection conductor is formed using different materials at the first and second ends including the both ends in the resin layer, and at least the first end is formed using a metal foil. Connected to the wiring conductor.

  In the above configuration, the interlayer connection conductor may include a portion made of a material different from that of the first end portion and the second end portion between the first end portion and the second end portion.

  According to the above configuration, since the interlayer connection conductors penetrating the resin layer have different materials for the first and second end portions, even if the wiring conductor connected to the first end portion is a metal foil, Each of the first end and the second end can be joined to the wiring conductor. In particular, by selecting a material having good bondability with the metal foil as a material for forming the first end portion, better bonding can be obtained. For example, after the second end portion is formed and the second end portion and the wiring conductor are joined, the first end portion is formed and the first end portion and another wiring conductor are joined. it can.

  Moreover, in order to solve the said subject, this invention provides the electronic component of the 2nd aspect comprised as follows.

  In the electronic component of the second aspect, (a) a ceramic layer in which an electrode is formed on the main surface, (b) a wiring conductor is disposed on one main surface, and the other main surface is in contact with the main surface of the ceramic layer. (C) the resin layer is penetrated in the thickness direction of the resin layer, the first end is connected to the wiring conductor, and the second end is connected to the electrode. Interlayer connection conductors. In the interlayer connection conductor, the first and second end portions are formed using different materials. The wiring conductor to which the first end of the interlayer connection conductor is connected is formed using a metal foil.

  According to the said structure, the electronic component provided with the resin layer on the ceramic substrate can be provided. Since the interlayer connection conductors penetrating the resin layer have different materials for the first and second end portions, even if the wiring conductor connected to the first end portion is a metal foil, the first end portion is It can be joined to the wiring conductor. In particular, by selecting a material having good bondability with the metal foil as a material for forming the first end portion, better bonding can be obtained. For example, after the second end portion is formed and the second end portion and the wiring conductor are joined, the first end portion is formed and the first end portion and another wiring conductor are joined. it can.

  In the electronic component of each aspect described above, preferably, the first end portion of the interlayer connection conductor is formed using a solder paste or a conductive paste containing a low melting point metal.

  In this case, the conductive paste containing the solder paste or the low melting point metal in a state where the wiring conductor is arranged adjacent to the first end of the interlayer connection conductor formed using the solder paste or the conductive paste containing the low melting point metal. Is heated, the conductive paste containing the solder paste or the low melting point metal melts and spreads on the wiring conductor, so that a highly reliable bonding interface is obtained.

  In the electronic component of each aspect described above, preferably, at least the wiring conductor connected to the first end is formed using a copper foil. The first end is made of a material mainly composed of copper.

  In this case, since the wiring conductors connected to each other and the first end of the interlayer connection conductor are both formed of a material mainly composed of Cu, both can be firmly joined. If Cu foil is used, a wiring conductor can be formed easily and inexpensively.

  In the electronic component of each aspect described above, the interlayer connection conductor is preferably formed using metal nanoparticles.

  In this case, the interlayer connection conductor can be finely processed, and the interlayer connection conductor can be miniaturized. In addition, the interlayer connection conductor and the wiring conductor can be reliably joined.

  In the electronic component according to the second aspect, preferably, the electrode disposed on the main surface of the ceramic layer and the second end of the connection conductor are made of a material mainly composed of silver. .

  In this case, since both the electrode formed on the main surface of the ceramic layer and the second end portion of the interlayer connection conductor are formed of a material mainly composed of Ag, both can be easily joined. When the ceramic layer electrode is formed of a material containing Ag as a main component, it is difficult to oxidize during firing.

  Moreover, in order to solve the said subject, this invention provides the manufacturing method of the electronic component comprised as follows.

  The electronic component manufacturing method includes (i) a first step of forming a lower post electrode on a first wiring conductor, and (ii) a second step of forming an upper post electrode on the lower post electrode. (Iii) a third step of forming a resin layer so as to cover the lower post electrode and the upper post electrode; and (iv) a metal foil so as to be in contact with the upper post electrode on the resin layer. And a fourth step of forming a second wiring conductor.

  According to the above method, the upper post electrode and the lower post electrode form an interlayer connection conductor that penetrates the resin layer. Since both ends of the interlayer connection conductor can be formed of different materials, select a material that has good bondability with the metal foil of the second wiring conductor as the material for forming the upper post electrode that is one end of the interlayer connection conductor By doing so, it is possible to obtain good bonding between the second conductor wiring and one end of the interlayer connection conductor.

  Preferably, the first wiring conductor is formed on a ceramic substrate.

  In this case, an electronic component having a resin layer on the ceramic substrate can be provided.

  Preferably, in the second step, the upper post electrode is formed using a solder paste or a conductive paste containing a low melting point metal.

  In this case, the solder paste or the low melting point metal of the upper post electrode is disposed in the state where the metal foil of the second wiring conductor is disposed adjacent to the upper post electrode formed using the solder paste or the conductive paste containing the low melting point metal. When the conductive paste containing is melted, the solder paste for the upper post electrode or the conductive paste containing the low melting point metal melts and spreads on the metal foil of the second wiring conductor, so that a highly reliable bonding interface is obtained.

  Preferably, the second wiring conductor is formed using a copper foil, and the upper post electrode is made of a material mainly composed of copper.

  In this case, since the second wiring conductor and the upper post electrode connected to each other are both formed of a material mainly composed of Cu, both can be firmly bonded. When Cu foil is used, the second wiring conductor can be formed easily and inexpensively.

  Preferably, the lower post electrode and the upper post electrode are formed using metal nanoparticles.

  In this case, the interlayer connection conductor can be finely processed, and the interlayer connection conductor can be miniaturized. In addition, the interlayer connection conductor and the first and second wiring conductors can be reliably joined.

  According to the present invention, the wiring conductor of the metal foil and the interlayer connection conductor can be joined.

It is sectional drawing which shows the manufacturing process of an electronic component. Example 1 It is sectional drawing which shows the manufacturing process of an electronic component. Example 1 It is sectional drawing which shows the manufacturing process of an electronic component. (Example 2) It is sectional drawing which shows the manufacturing process of an electronic component. (Example 2) It is sectional drawing which shows the manufacturing process of an electronic component. (Example 3) It is sectional drawing which shows the manufacturing process of an electronic component. (Example 3) It is explanatory drawing which shows the manufacturing process of an electronic component. (Conventional example)

  Embodiments of the present invention will be described below with reference to FIGS.

  <Example 1> The electronic component 1 of Example 1 is demonstrated referring FIG.1 and FIG.2. 1 and 2 are cross-sectional views showing the manufacturing process of the electronic component 1.

  As shown in FIG. 2 (i), the electronic component 1 includes a plurality of resin layers 30, 30x, 30y, and 30z that are laminated, and wiring conductors 10p to 10r, on the main surfaces of the resin layers 30, 30x, 30y, and 30z. 12p-12r, 14p-14r, 16p-16r, 18p-18r are formed. The resin layers 30, 30x, 30y, and 30z penetrate the resin layers 30, 30x, 30y, and 30z, and both ends are connected to the wiring conductors 10p to 10r, 12p to 12r, 14p to 14r, 16p to 16r, and 18p to 18r. Interlayer connection conductors 11, 13, 15, and 17 are formed. In each of the interlayer connection conductors 11, 13, 15, and 17, the upper post electrodes 22, 22x to 22z and the lower post electrodes 20, 20x to 20z are formed of different materials. The upper post electrodes 22, 22 x to 22 z are first end portions including one of both ends of the interlayer connection conductors 11, 13, 15, and 17. The lower post electrodes 20, 20 x to 20 z are second ends including the other of both ends of the interlayer connection conductors 11, 13, 15, 17.

  The wiring conductors 18p to 18r formed on the upper surface 1p of the electronic component 1 are mounting electrodes on which electronic components such as semiconductor elements and chip components are mounted. The wiring conductors 10p to 10r formed on the lower surface 1q of the electronic component 1 are connection electrodes for connecting the electronic component 1 to another circuit board or the like.

  The electronic component 1 can be produced by the following steps (1) to (8).

  (1) First, as shown in FIG. 1A, a Cu foil 10 is prepared.

  (2) Next, as shown in FIG. 1 (b), a lower post electrode 20 to be a lower part of the interlayer connection conductor 11 is formed on the upper surface 10 a of the Cu foil 10.

  Specifically, Cu nanoparticles (particles having a diameter of less than 1 μm, for example, particles having a diameter of about 1 to 100 nm) are formed by inkjet on the upper surface 10a of the Cu foil 10 up to about half the height of the interlayer connection conductor 11 to be formed. ), And then heated at 230 ° C. for 60 minutes. The nano Cu ink is cured by heating, and the lower post electrode 20 joined to the upper surface 10a of the Cu foil 10 is formed. Since both the lower post electrode 20 and the Cu foil 10 are formed of a material mainly containing Cu, both are firmly bonded.

  In the present embodiment, the lower post electrode 20 is formed using nano Cu ink, but is not limited to nano ink, and may be formed using a normal conductive paste. The Cu foil 10 is not limited to a Cu metal foil, and a metal foil such as a Ni foil, an aluminum foil, or a silver foil may be used. In that case, it is preferable to use a conductive paste having the same main component as the metal foil. Furthermore, instead of the Cu foil 10, a wiring conductor formed using a conductive paste may be used.

  (3) Next, as shown in FIG. 1C, an upper post electrode 22 that is to be an upper part of the interlayer connection conductor 11 is formed on the upper surface 20 a of the lower post electrode 20.

  Specifically, after applying a solder paste made of Sn-Ag-Cu containing copper as a main component to the upper surface 20a of the lower post electrode 20 so as to be the height of the interlayer connection conductor 11 to be formed, The upper post electrode 22 bonded to the upper surface 20a of the lower post electrode 20 is formed by heating the solder paste at a temperature of 220 ° C. or higher and 240 ° C. or lower for 1 minute to cure the solder paste.

  The solder paste is not limited to Sn—Ag—Cu, and solder paste such as Sn—Ag, Sn—Cu can be used. The upper post electrode 22 may be a conductive paste containing a low melting point metal. The low melting point metal is a metal that melts in the step of joining the upper post electrode 22 and the Cu foil 12, which will be described later, and a conductive paste mainly composed of Sn, Sn—Ag—Cu, Sn—Bi, Zn, or the like. It is.

  (4) Next, as shown in FIG. 1 (d), a resin layer 30 is formed on the upper surface 10 a of the Cu foil 10. The upper post electrode 22 is exposed from the upper surface 30 a of the resin layer 30. In FIG. 1D, the upper post electrode 22 protrudes from the upper surface 30 a of the resin layer 30, but the height thereof may be the same as the upper surface 30 a of the resin layer 30. Further, after forming the resin layer 30 so as to fill the upper post electrode 22, the resin layer 30 may be ground to expose the upper post electrode 22.

  Specifically, after placing an uncured resin sheet made of a thermosetting resin such as an epoxy resin with an inorganic filler on the upper surface 30a of the resin layer 30, it is 10 minutes at a temperature of 100 ° C. or more and 150 ° C. or less under vacuum The resin sheet is thermocompression bonded. Thereby, after the interlayer connection conductor 11 is penetrated through the resin sheet, the resin sheet is cured to form the resin layer 30 in which the upper post electrode 22 is exposed on the upper surface 30a.

  (5) Next, as shown in FIG. 1 (e), the Cu foil 12 is bonded to the upper surface 30 a of the resin layer 30.

  Specifically, the Cu foil 12 is pressure-bonded to the upper surface 30a of the resin layer 30 and heated at 230 ° C. for 30 minutes to join the upper post electrode 22 and the Cu foil 12 together. Since the upper post electrode 22 protruding from the upper surface 30a of the resin layer 30 is melted again by heating and spreads on the Cu foil 12, a highly reliable bonding interface is obtained between the Cu foil 12 and the upper post electrode 22. be able to. At this time, the surplus portion of the melted upper post electrode 22 enters the gap between the resin layer 30 and the Cu foil 12, so that variations in the height of the upper post electrode 22 can be absorbed. Since the upper post electrode 22 and the Cu foil 12 are both made of a material mainly composed of Cu, both are firmly bonded.

  (6) Next, as shown in FIG. 2F, the Cu foil 12 is patterned into a predetermined shape constituting an electric circuit by using a photolithography technique and an etching technique to form wiring conductors 12p to 12r. .

  That is, a photoresist is applied, exposed and developed on the upper surface 12a of the Cu foil 12 to form a mask pattern. After etching the Cu foil 12 through the mask pattern, the mask pattern is removed using a stripping solution.

  (7) Hereinafter, similarly, the steps (2) to (6) are repeated to form the resin layer 30x, the post electrode 13, and the wiring conductors 14p to 14r as shown in FIG. Furthermore, the steps (2) to (6) are repeated twice, and as shown in FIG. 2 (h), the resin layers 30, 30x to 30z are laminated, and the laminate having the Cu foils 10, 18 on both sides in the lamination direction. Form. However, the last step (6) is not performed and the uppermost Cu foil 18 is not patterned.

  (8) Next, as shown in FIG. 2 (i), the Cu conductors 10 and 18 on both sides in the stacking direction of the stacked body are patterned using a photolithography technique and an etching technique to form wiring conductors 18p to become mounting electrodes. Wiring conductors 10p to 10r that form connection electrodes 18r are formed.

  Through the steps (1) to (8), the electronic component 1 in which an electric circuit is configured is completed.

  The wiring conductors 10p to 10r, 12p to 12r, 14p to 14r, 16p to 16r, and 18p to 18r of the electronic component 1 can be easily and inexpensively formed using Cu foil.

  The lower post electrodes 20 and 20x to 20z of the electronic component 1 can be finely processed by using a nano Cu ink, and can be miniaturized. Further, the lower post electrodes 20, 20x to 20z can be reliably bonded to the wiring conductors 10p to 10r, 12p to 12r, 14p to 14r, and 16p to 16r.

  Example 2 An electronic component 1a of Example 2 will be described with reference to FIGS. 3 and 4 are cross-sectional views showing the manufacturing process of the electronic component 1a.

  The electronic component 1a of the second embodiment has a configuration that is substantially the same as the electronic component 1 of the first embodiment. In the following, the same reference numerals are used for the same components as in the first embodiment, and differences from the first embodiment will be mainly described.

  As shown in FIG. 4 (h), in the electronic component 1a according to the second embodiment, a plurality of resin layers 30k, 30x, and 30y are stacked as in the first embodiment, and the main surfaces of the resin layers 30k, 30x, and 30y are stacked. Wiring conductors 12p to 12r, 14p to 14r, and 16p to 16r are formed. The resin layers 30k, 30x, and 30y penetrate through the resin layers 30k, 30x, and 30y, and interlayer connection conductors 11a, 13a, and 15a connected to the wiring conductors 12p to 12r, 14p to 14r, and 16p to 16r are formed. . In each interlayer connection conductor 11a, 13a, 15a, the upper post electrodes 26, 26p, 26q and the lower post electrodes 24, 24p, 24q are formed of different materials. The upper post electrodes 26, 26p, and 26q are first end portions including one of both ends of the interlayer connection conductors 11a, 13a, and 15a. The lower post electrodes 24, 24p, and 24q are second end portions including the other of both ends of the interlayer connection conductors 11a, 13a, and 15a.

  The wiring conductors 16p to 16r formed on the upper surface 1s of the electronic component 1a are mounting electrodes for mounting an electronic component such as a semiconductor element or a chip component, or for connecting the electronic component 1a to another circuit board or the like. It is a connection electrode.

  Unlike the first embodiment, the electronic component 1a further includes a ceramic substrate 2 stacked together with the resin layers 30k, 30x, and 30y, and an electronic component 8 disposed between the ceramic substrate 2 and the resin layer 30k. . Electrodes 4 and 6 are formed on the upper surface 2a of the ceramic substrate 2 on which the resin layer 30k is laminated. The lower electrode post 24 of the interlayer connection conductor 11a penetrating the resin layer 30k is connected to the electrode 4, and the electrode 6 is a component. 8 is implemented.

  Although not shown, mounting electrodes and connection electrodes may be formed on the lower surface of the electronic component 1a, that is, the lower surface 2b of the ceramic substrate 2.

  The electronic component 1a can be manufactured by the following steps (1) to (8).

  (1) First, as shown in FIG. 3A, a ceramic substrate 2 having electrodes 4 and 6 formed on an upper surface 2a is prepared. The electrodes 4 and 6 are formed of a material mainly composed of Ag that is difficult to oxidize when the ceramic substrate 2 is fired.

  (2) Next, as shown in FIG. 3 (b), a lower post electrode 24 is formed on the electrode 4 of the ceramic substrate 2 to be a lower part of the interlayer connection conductor 11 a.

  Specifically, nano-Ag ink containing Ag nanoparticles is applied to the electrode 4 of the ceramic substrate 2 to about half the height of the interlayer connection conductor 11a to be formed, and then heated at 230 ° C. for 30 minutes. The nano Ag ink is cured to some extent by heating to form the lower post electrode 24 bonded to the electrode 4 of the ceramic substrate 2. Since both the electrode 4 and the lower post electrode 24 of the ceramic substrate 2 are formed of a material mainly composed of Ag, the two are firmly bonded.

  In this embodiment, the lower post electrode 24 is formed using nano Ag ink. However, the lower post electrode 24 is not limited to nano ink, and may be formed using a normal conductive paste. In this embodiment, the electrodes 4 and 6 are not limited to Ag, and may be formed of a material mainly composed of Ni, aluminum, Zn, or the like. In that case, it is preferable to use a conductive paste having the same main component as the metal foil.

  (3) Next, as shown in FIG. 3C, the upper post electrode 26 that is the upper portion of the interlayer connection conductor 11 a is formed on the upper surface 24 a of the lower post electrode 24.

  Specifically, after applying a nano Cu ink containing Cu nanoparticles by ink jet so as to be the height of the interlayer connection conductor 11a to be formed, heating is performed at 230 ° C. for 30 minutes. The nano Cu ink is cured to some extent by heating to form the upper post electrode 26 bonded to the upper surface 24 a of the lower post electrode 24. At this time, the lower post electrode 24 which has been cured to some extent is further heated and completely cured.

  In the present embodiment, the upper post electrode 26 is formed using nano Cu ink, but is not limited to nano ink, and may be formed using a normal conductive paste.

  In order to apply the nano Cu ink of the upper post electrode 26 to the upper surface 24a of the lower post electrode 24 that has been cured to a certain extent, the nano Cu ink of the upper post electrode 26 is applied to the upper surface 24a of the completely cured lower post electrode 24. The upper post electrode 26 can be joined to the lower post electrode 24 more firmly than in the case of doing so.

  (4) Next, as shown in FIG. 3D, an electronic component 8 such as an active element such as a semiconductor, a receiving element such as a capacitor, an inductor, or a resistor is mounted on the other electrode 6 of the ceramic substrate 2. .

  Specifically, solder is applied onto the electrode 6 of the ceramic substrate 2 using a dispenser, and the electronic component 8 is mounted thereon.

  (5) Next, as shown in FIG. 3E, a resin layer 30 k is formed on the upper surface 2 a of the ceramic substrate 2. The upper post electrode 26 is exposed from the upper surface 30s of the resin layer 30k. Although the upper post electrode 26 protrudes from the upper surface 30s of the resin layer 30k in FIG. 3E, the height thereof may be the same as the upper surface 30s of the resin layer 30k. Alternatively, after the resin layer 30k is formed so as to fill the upper post electrode 26, the upper post electrode 26 may be exposed by grinding the resin layer 30k.

  Specifically, after placing an uncured resin sheet made of a thermosetting resin such as an epoxy resin containing an inorganic filler on the upper surface 2a of the ceramic substrate 2, it is 10 minutes at a temperature of 100 ° C. or more and 150 ° C. or less under vacuum. The resin sheet is thermocompression bonded. Thus, after the interlayer connection conductor 11a is passed through the resin sheet, the resin sheet is cured to form the resin layer 30k with the upper post electrode 26 exposed on the upper surface 30s.

  (6) Next, as shown in FIG. 3F, the Cu foil 12 is bonded to the upper surface 30s of the resin layer 30k.

  Specifically, the Cu foil 12 is pressure-bonded to the upper surface 30 s of the resin layer 30 k and heated at 230 ° C. for 30 minutes to join the upper post electrode 26 and the Cu foil 12. The upper post electrode 26 protruding from the upper surface 30 s of the resin layer 30 k is cured by heating and joined to the Cu foil 12. At this time, since the upper post electrode 26 cured to a certain degree is heated while being in contact with the Cu foil 12, the upper post electrode 26 can be joined to the Cu foil 12. Since the upper post electrode 26 and the Cu foil 12 are both made of a material mainly composed of Cu, both are firmly bonded.

  At the same time, the solder on the electrode 6 of the ceramic substrate 2 is heated and cured, and the electronic component 8 is joined to the electrode 6.

  (7) Next, as shown in FIG. 4G, the Cu foil 12 is patterned into a predetermined shape constituting an electric circuit by using a photolithography technique and an etching technique to form wiring conductors 12p to 12r. .

  That is, a photoresist is applied, exposed and developed on the upper surface 12a of the Cu foil 12 to form a mask pattern. After etching the Cu foil 12 through the mask pattern, the mask pattern is removed using a stripping solution.

  (8) Hereinafter, similarly, the steps (2) to (6) are repeated, and as shown in FIG. 4 (h), the resin layers 30x and 30y, the post electrodes 13a and 15a, and the wiring conductors 14p to 14r, 16p to 16r are formed.

  However, the lower post electrodes 24p and 24q of the interlayer connection conductors 13a and 15a are formed using nano Cu ink. Thereby, lower post electrode 24p, 24q can be firmly joined to wiring conductors 12p-12r, 14p-14r formed with Cu foil.

  Through the steps (1) to (8), the electronic component 1a in which an electric circuit including the electronic component 8 is configured is completed.

  The wiring conductors 12p to 12r, 14p to 14r, and 16p to 16r of the electronic component 1a can be easily and inexpensively formed using Cu foil.

  Since the lower post electrode 24 of the electronic component 1a is formed using nano Ag ink, and the lower post electrodes 24p, 24q and the upper post electrodes 26, 26p, 26q are formed using nano Cu ink, the interlayer connection conductor 11a , 13a and 15a can be finely processed and can be miniaturized. Further, the interlayer connection conductors 11a, 13a, and 15a can be reliably bonded to the Cu foil wiring conductors 12p to 12r, 14p to 14r, and 16p to 16r.

  <Modification of Example 2> In the modification of Example 2, the upper post electrode 26 is formed using a solder paste made of Sn-Ag-Cu containing copper as a main component. Different. Other configurations are the same as those in the second embodiment.

  For example, a solder paste made of Sn—Ag—Cu containing copper as a main component is applied to the upper surface 24a of the lower post electrode 24 using a dispense, and then heated at a temperature of 220 ° C. or higher and 240 ° C. or lower for 1 minute. The solder paste is cured to form the upper post electrode 26 joined to the upper surface 24a of the lower post electrode 24. The solder paste is not limited to Sn—Ag—Cu, and solder paste such as Sn—Ag, Sn—Cu can be used. Further, the upper post electrode 26 may be a conductive paste containing a low melting point metal. The low melting point metal is a metal that melts in the step of joining the upper post electrode 26 and the Cu foil 12 described later, and is a conductive paste mainly composed of Sn, Sn—Ag—Cu, Sn—Bi, Zn, or the like. It is.

  <Example 3> The electronic component 1b of Example 3 is demonstrated referring FIG.5 and FIG.6. 5 and 6 are cross-sectional views showing the manufacturing process of the electronic component 1b.

  As shown in FIG. 6, the electronic component 1b of the third embodiment is different from the second embodiment in that the electronic component 1b has a resin layer 32 on both sides of a ceramic multilayer substrate 2k in which a plurality of ceramic layers 2p and 2q are laminated. , 32p to 32t are stacked.

  As in the first and second embodiments, the electronic component 1b includes (a) a plurality of laminated resin layers 30k and 30u to 30y, and (b) a wiring conductor formed on the main surface of the resin layers 30k and 30u to 30y. 12p-12u, 14p-14u, 16p-16u, and (c) interlayer connection conductors 11a, 11b penetrating through the resin layers 30k, 30u-30y and connected to the wiring conductors 12p-12u, 14p-14u, 16p-16u , 13a, 13b, 15a, 15b. Each of the interlayer connection conductors 11a, 11b, 13a, 13b, 15a, and 15b includes an upper post electrode 26, 26p to 26t that is one end on the ceramic multilayer substrate 2k side, and a lower post electrode that is the other end. 24, 24p to 24t are made of different materials. The upper post electrodes 26, 26p to 26t are first end portions including one of both ends of the interlayer connection conductors 11a, 11b, 13a, 13b, 15a, 15b. The lower post electrodes 24, 24p to 24t are second end portions including the other of both ends of the interlayer connection conductors 11a, 11b, 13a, 13b, 15a, 15b.

  The electronic component 1b can be manufactured in substantially the same process as in Example 2 as in the following (1) to (7).

  (1) First, as shown in FIG. 5A, a ceramic multilayer substrate 2k having electrodes 4 and 6 formed on the upper surface 2s is prepared, and an active element such as a semiconductor, a capacitor, an inductor, a resistor, and the like are provided on the electrode 6. An electronic component 8 such as a receiving element is mounted.

  Specifically, solder is applied to the electrodes 6 of the ceramic multilayer substrate 2k by screen printing or using a dispenser, and the electronic component 8 is mounted thereon.

  (2) Next, as shown in FIG. 5 (b), a lower post electrode 24 to be a lower part of the interlayer connection conductor 11a is formed on the electrode 4 of the ceramic multilayer substrate 2k.

  Specifically, nano-Ag ink containing Ag nanoparticles is applied to the upper surface 2s of the ceramic multilayer substrate 2k to about half the height of the interlayer connection conductor 11a to be formed, and then heated at 230 ° C. for 30 minutes. The nano Ag ink is cured to a certain extent by heating, and the lower post electrode 24 that is well connected to the electrode 4 of the ceramic multilayer substrate 2k is formed.

  At the same time, the solder on the electrode 6 of the ceramic multilayer substrate 2k is heated and cured, and the electronic component 8 is joined to the electrode 6.

  (3) Next, as shown in FIG. 5C, the upper post electrode 26 that is the upper part of the interlayer connection conductor 11 a is formed on the upper surface 24 a of the lower post electrode 24.

  Specifically, after applying a nano Cu ink containing Cu nanoparticles by inkjet so as to be the height of the interlayer connection conductor 11a to be formed, heating is performed at 230 ° C. for 30 minutes. The nano Cu ink is cured to some extent by heating to form the upper post electrode 26 bonded to the upper surface 24 a of the lower post electrode 24. The lower post electrode 24 is completely cured by heating at this time.

  In order to apply the nano Cu ink of the upper post electrode 26 to the upper surface 24a of the lower post electrode 24, which has been cured to some extent, the nano Cu ink of the upper post electrode 26 is applied to the upper surface 24a of the completely cured lower post electrode 24. The upper post electrode 26 can be joined to the lower post electrode 24 more firmly than in the case.

  (4) Next, as shown in FIG. 5D, a resin layer 30k is formed on the upper surface 2s of the ceramic multilayer substrate 2k. The upper post electrode 26 is exposed on the upper surface 30s of the resin layer 30k.

  Specifically, after an uncured resin sheet made of a thermosetting resin such as an epoxy resin containing an inorganic filler is placed on the upper surface 2s of the ceramic multilayer substrate 2k, it is 10 minutes at a temperature of 100 ° C. or more and 150 ° C. or less under vacuum. The resin sheet is thermocompression bonded. Thus, after the interlayer connection conductor 11a is penetrated through the resin sheet, the resin sheet is cured to form the resin layer 30k with the upper post electrode 26 exposed on the upper surface 30s.

  (5) Next, as shown in FIG. 5E, the Cu foil 12 is joined to the upper surface 30s of the resin layer 30k.

  Specifically, the Cu foil 12 is pressure-bonded to the upper surface 30 s of the resin layer 30 k and heated at 230 ° C. for 30 minutes to join the upper post electrode 26 and the Cu foil 12. At this time, since the upper post electrode 26 cured to a certain degree is heated while being in contact with the Cu foil 12, the upper post electrode 26 can be joined to the Cu foil 12. Since the upper post electrode 26 and the Cu foil 12 are both made of a material mainly composed of Cu, both are firmly bonded.

  (6) Next, as shown in FIG. 6F, the Cu foil 12 is patterned into a predetermined shape constituting an electric circuit by using a photolithography technique and an etching technique to form wiring conductors 12p to 12r. .

  That is, a photoresist is applied, exposed and developed on the upper surface 12a of the Cu foil 12 to form a mask pattern. After etching the Cu foil 12 through the mask pattern, the mask pattern is removed using a stripping solution.

  (7) Hereinafter, similarly, the steps (2) to (6) are repeated, and as shown in FIG. 6G, the resin layers 30x and 30y and the interlayer connection conductor are formed on the upper surface 2s side of the ceramic multilayer substrate 2k. 13a and 15a and wiring conductors 14p to 14r and 16p to 16r are formed. The steps (1) to (6) are repeated in the same manner, and the resin layers 30u to 30w, the interlayer connection conductors 11b, 13b and 15b, and the wiring conductors 12s to 12u and 14s are formed on the lower surface 2t side of the ceramic multilayer substrate 2k. To 14u, 16s to 16u are formed.

  Through the steps (1) to (7), the electronic component 1b in which an electric circuit including the electronic component 8 is configured is completed.

  The interlayer connection conductors 11a, 11b, 13a, 13b, 15a, and 15b of the electronic component 1b can be finely processed using nano Ag ink or nano Cu ink, and can be miniaturized. Further, the interlayer connection conductors 11a, 11b, 13a, 13b, 15a, and 15b and the wiring conductors 10p to 10r, 12p to 12r, 14p to 14r, and 16p to 16r can be reliably joined.

  The electronic component 1b can be manufactured in the same manner as in the first embodiment. In this case, for example, the upper post electrodes 26, 26p to 26t are formed using a solder paste.

  <Summary> As described above, by forming one end and the other end of the interlayer connection conductor with different materials, the end of the interlayer connection conductor can be joined to the wiring conductor formed of metal foil. it can.

  The present invention is not limited to the above embodiment, and can be implemented with various modifications.

  For example, the interlayer connection conductor may include a portion made of a material different from that of the first end portion and the second end portion between the first end portion and the second end portion.

1, 1a, 1b Electronic component 2 Ceramic substrate
2k Ceramic multilayer substrate 4 Electrode 10 Cu foil 10p-10r Wiring conductor 11, 11a, 11b Interlayer connection conductor 12 Cu foil 12p-12u Wiring conductor 13, 13a, 13b Interlayer connection conductor 14p-14u Wiring conductor 15, 15a, 15b Interlayer connection Conductor 16p to 16u Wiring conductor 17 Interlayer connection conductor 18 Cu foil 18p to 18r Wiring conductor 20, 20x to 20z Lower post electrode (second end)
22, 22x-22z Upper post electrode (first end)
24, 24p to 24t Lower post electrode (second end)
26, 26p to 26t Upper post electrode (first end)
30, 30k, 30u-30z resin layer

Claims (12)

A resin layer having a pair of main surfaces facing each other;
Wiring conductors respectively disposed on the main surface of the resin layer;
An interlayer connection conductor that penetrates the resin layer in the thickness direction of the resin layer and has both ends connected to the wiring conductor;
Including
The interlayer connection conductor is formed using different materials at the first and second ends including the both ends in the resin layer, and at least the first end is formed using a metal foil. An electronic component, wherein the electronic component is connected to the wiring conductor. A ceramic layer with electrodes formed on the main surface;
A wiring layer is disposed on one main surface, and a resin layer laminated so that the other main surface is in contact with the main surface of the ceramic layer;
An interlayer connection conductor that penetrates the resin layer in the thickness direction of the resin layer, has a first end connected to the wiring conductor, and a second end connected to the electrode;
Including
The interlayer connection conductor is formed by using different materials for the first and second ends.
The electronic component, wherein the wiring conductor to which the first end portion of the interlayer connection conductor is connected is formed using a metal foil.   The electronic component according to claim 1, wherein the first end portion of the interlayer connection conductor is formed using a solder paste or a conductive paste containing a low melting point metal. The wiring conductor connected to at least the first end is formed using copper foil,
The electronic component according to claim 1, wherein the first end portion is made of a material mainly composed of copper.   The electronic component according to claim 1, wherein the interlayer connection conductor is formed using metal nanoparticles.   The said electrode formed in the said main surface of the said ceramic layer and the said 2nd edge part of the said interlayer connection conductor consist of a material which has silver as a main component, The feature of Claim 2 characterized by the above-mentioned. Electronic components. A first step of forming a lower post electrode on the first wiring conductor;
A second step of forming an upper post electrode on the lower post electrode;
A third step of forming a resin layer so as to cover the lower post electrode and the upper post electrode;
A fourth step of forming a second wiring conductor using a metal foil so as to be in contact with the upper post electrode on the resin layer;
An electronic component manufacturing method comprising:   The method of manufacturing an electronic component according to claim 7, wherein the first wiring conductor is formed on a ceramic substrate.   9. The method of manufacturing an electronic component according to claim 7, wherein in the second step, the upper post electrode is formed using a solder paste or a conductive paste containing a low melting point metal.   9. The method of manufacturing an electronic component according to claim 7, wherein the second wiring conductor is formed using a copper foil, and the upper post electrode is made of a material containing copper as a main component.   11. The method of manufacturing an electronic component according to claim 7, wherein the lower post electrode and the upper post electrode are formed using metal nanoparticles. 11.   9. The method of manufacturing an electronic component according to claim 8, wherein the first wiring conductor and the lower post electrode are made of a material mainly composed of silver.

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