阅读说明：本技术 连接电极及连接电极的制造方法 (Connection electrode and method for manufacturing connection electrode ) 是由 坂井亮介 于 2019-09-03 设计创作，主要内容包括：连接电极具备金属膜(40)、金属膜(50)、混合层(45)及UBM(80)。金属膜(50)形成在金属膜(40)上,UBM(80)形成在金属膜(50)上。混合层(45)是形成金属膜(40)的金属颗粒(P40)与形成金属膜(50)的金属颗粒(P50)混合的层。在沿金属膜(40)及金属膜(50)排列的第一方向观察时,混合层(45)的至少一部分形成在与UBM(80)和金属膜(50)的接合面重叠的第一区域(Re1)。(The connection electrode is provided with a metal film (40), a metal film (50), a mixed layer (45), and a UBM (80). A metal film (50) is formed on the metal film (40), and a UBM (80) is formed on the metal film (50). The mixed layer (45) is a layer in which the metal particles (P40) forming the metal film (40) are mixed with the metal particles (P50) forming the metal film (50). At least a part of the mixed layer (45) is formed in a first region (Re1) that overlaps the bonding surface of the UBM (80) and the metal film (50) when viewed in a first direction in which the metal film (40) and the metal film (50) are aligned.)

1. A connection electrode is provided with:

a first metal film formed on a main surface of the wiring electrode;

a second metal film formed on a surface of the first metal film opposite to a surface of the first metal film which is in contact with the wiring electrode;

a lead-out electrode formed on a surface of the second metal film opposite to the surface of the second metal film that is in contact with the first metal film; and

a mixed layer in which first metal particles forming the first metal film are mixed with second metal particles forming the second metal film,

at least a part of the mixed layer is formed in a first region overlapping a bonding surface between the extraction electrode and the second metal film when viewed in a first direction in which the first metal film, the second metal film, and the extraction electrode are aligned.

2. The connection electrode according to claim 1,

the mixed layer is not formed in a second region that does not overlap with a bonding surface between the extraction electrode and the second metal film when viewed in the first direction.

3. The connection electrode according to claim 1,

the mixed layer is formed in a part of a second region that does not overlap with a bonding surface of the extraction electrode and the second metal film when viewed in the first direction,

a region of the second region in which the mixed layer is formed is smaller than a region of the second region in which the other portion of the mixed layer is not formed.

4. The connection electrode according to claim 3,

the mixed layer is not formed in a third region on a side opposite to the first region side with the second region interposed therebetween, as viewed in a second direction parallel to a contact surface of the first metal film and the second metal film.

5. The connection electrode according to claim 4,

the connection electrode further includes a support frame which is formed on the second metal film and includes at least a part of the extraction electrode therein,

the second region is a region overlapping with the support frame when viewed in the first direction,

the third region is a region that does not overlap with the support frame when viewed in the first direction.

6. The connection electrode according to any one of claims 1 to 5,

the second metal film is less susceptible to oxidation than the first metal film.

7. The connection electrode according to any one of claims 1 to 6,

the mixed layer does not reach an abutment surface of the second metal film that abuts the extraction electrode in the first direction.

8. The connection electrode according to claim 7,

the mixed layer does not reach an abutment surface of the first metal film that abuts against the wiring electrode in the first direction.

9. The connection electrode according to any one of claims 1 to 7,

the mixed layer reaches the wiring electrode.

10. The connection electrode according to any one of claims 1 to 9,

the wiring electrode has a lower resistivity than the first metal film and the second metal film.

11. The connection electrode according to any one of claims 1 to 10,

the first metal particles comprise titanium, nickel or chromium,

the second metal particles comprise platinum or gold,

the third metal particles constituting the wiring electrode contain copper or aluminum.

12. A connection electrode is provided with:

a first metal film formed on a main surface of the wiring electrode;

a lead-out electrode formed on a surface of the first metal film opposite to a surface of the first metal film that is in contact with the wiring electrode; and

a mixed layer in which first metal particles forming the first metal film are mixed with third metal particles forming the wiring electrode,

at least a part of the mixed layer is formed in a first region overlapping a bonding surface between the extraction electrode and the first metal film when viewed in a first direction in which the first metal film and the extraction electrode are arranged.

13. A method for manufacturing a connection electrode includes the steps of:

forming a first metal film on a main surface of the wiring electrode;

forming a second metal film on a surface of the first metal film opposite to a surface of the first metal film which is in contact with the wiring electrode;

forming an insulating layer covering at least a part of a surface of the second metal film opposite to the surface abutting against the first metal film;

irradiating the insulating layer with laser light to form a through hole exposing the second metal film;

forming a mixed layer in which first metal particles constituting the first metal film and second metal particles constituting the second metal film are mixed by irradiating the laser light forming the through hole to the second metal film and the first metal film and heating the laser light; and

and forming an extraction electrode in the through hole.

Technical Field

The present invention relates to a structure of a connection electrode of an electronic component and a method for manufacturing the same.

Background

Patent document 1 describes a structure of a connection electrode of an acoustic wave device. In the structure of the connection electrode of patent document 1, the electrode land is formed on the substrate, and the metal film is formed on the electrode land. In addition, an under-bump metal (under-bump metal) is formed on the metal film.

Prior art documents

Patent document

Patent document 1: japanese patent No. 5510695

Disclosure of Invention

Problems to be solved by the invention

Here, another metal film (second metal film) may be further formed on the metal film (first metal film) of patent document 1, and an under bump metal may be formed on the second metal film. In the structure in which a plurality of metal films are stacked as described above, various effects that are not easily achieved in the structure in which only one metal film is formed may be obtained.

However, in a structure in which a plurality of metal films are stacked, the surface of the first metal film may be oxidized. In this case, the resistance increases at the joint between the first metal film and the second metal film. Therefore, the resistance as the connection electrode increases, and the electrical characteristics deteriorate.

Accordingly, an object of the present invention is to provide a structure and a method for manufacturing the same, in which a connection electrode having a structure in which a plurality of metal films are stacked can suppress a decrease in electrical characteristics.

Means for solving the problems

The connection electrode of the present invention includes a first metal film, a second metal film, a lead-out electrode, and a mixed layer. The first metal film is formed on the main surface of the wiring electrode. The second metal film is formed on a surface of the first metal film opposite to the surface of the first metal film that is in contact with the wiring electrode. The extraction electrode is formed on a surface of the second metal film opposite to the surface of the second metal film that is in contact with the first metal film. The mixed layer is a layer in which first metal particles forming the first metal film and second metal particles forming the second metal film are mixed. At least a part of the mixed layer is formed in a first region overlapping a junction surface of the extraction electrode and the second metal film when viewed in a first direction in which the first metal film, the second metal film, and the extraction electrode are arranged.

In this structure, by forming a mixed layer of the first metal particles and the second metal particles in the first metal film and the second metal film, the resistivity at the portion directly below the extraction electrode is lowered. This reduces the resistance of a path connecting the wiring electrode to the extraction electrode through the first metal film and the second metal film.

Effects of the invention

According to the present invention, it is possible to suppress a decrease in electrical characteristics in a connection electrode having a structure in which a plurality of metal films are stacked.

Drawings

Fig. 1 is a side sectional view showing a structure of a connection electrode of an embodiment of the present invention.

Fig. 2 is an enlarged side sectional view of a part of the connection electrode.

Fig. 3 is a diagram schematically showing a mixed state of the metal particles P40, P50.

Fig. 4 is a flowchart illustrating a method of manufacturing a connection electrode according to an embodiment of the present invention.

Fig. 5 (a), (B), and (C) are diagrams showing respective states of the manufacturing process of the connection electrode.

Fig. 6 is a side sectional view showing an example of a derivative of the structure of the connection electrode according to the embodiment of the present invention.

Detailed Description

A connection electrode and a method for manufacturing the connection electrode according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a side sectional view showing a structure of a connection electrode of an embodiment of the present invention. Fig. 2 is an enlarged side sectional view of a part of the connection electrode.

As shown in fig. 1 and 2, an electronic component 10 having connection electrodes according to the present embodiment includes a substrate 20, wiring electrodes 30, a metal film 40, a metal film 50, a support frame 60, a cover layer 70, an under bump metallurgy 80 (hereinafter referred to as UBM80), and solder balls 81. The portion including the metal film 40, the metal film 50, and the UBM80 corresponds to a "connection electrode" of the present invention.

The substrate 20 is, for example, a flat plate and has a planar main surface 201. When the substrate 20 is a flat plate, the substrate 20 has another main surface facing the main surface 201, which is not shown. The substrate 20 is realized by, for example, a piezoelectric substrate, a semiconductor substrate, or an insulating substrate. When the substrate 20 is a piezoelectric substrate, for example, IDT electrodes and the like are formed on the piezoelectric substrate. When the substrate 20 is a semiconductor substrate, a diode, a transistor, an FET, or the like is formed on the semiconductor substrate, for example. When the substrate 20 is an insulating substrate, a conductor pattern for realizing a predetermined electric circuit is formed on the insulating substrate, for example.

The wiring electrode 30 is formed on the main surface 201 of the substrate 20. The wiring electrode 30 is a flat film and has a main surface 301 and a main surface 302 facing each other. The main surface 301 abuts the main surface 201 of the substrate 20. The main surface 302 is a surface of the wiring electrode 30 opposite to the surface in contact with the substrate 20.

The wiring electrode 30 is formed of a material having a relatively low resistivity, such as aluminum (Al) or copper (Cu). The metal having a relatively low resistivity means, for example, a metal classified into various metals having a relatively low resistivity. That is, the wiring electrode 30 may have a resistivity in a practical range according to the specification of the electronic component 10. The resistivity of the wiring electrode 30 is preferably lower than the resistivity of the metal film 40 and the resistivity of the metal film 50. This can reduce the wiring resistance with respect to the substrate 20, and can improve the electrical characteristics of the electronic component 10. The wiring electrode 30 is preferably formed of a material that is easy to process. Further, aluminum (Al), copper (Cu), or the like constituting the wiring electrode 30 corresponds to the "third metal particles" of the present invention.

The wiring electrode 30 is connected to an electrode such as an IDT electrode, a conductor pattern, and the like via a wiring not shown in fig. 1, for example.

The metal film 40 is formed on the main surface 302 of the wiring electrode 30. The metal film 40 is a flat film and has a main surface 401 and a main surface 402 facing each other. The main surface 401 abuts against the main surface 302 of the wiring electrode 30. The main surface 402 is a surface of the metal film 40 opposite to the surface in contact with the wiring electrode 30.

The metal film 40 is formed by evaporation, plating, sputtering, or the like. The thickness of the metal film 40 (the length in the first direction in fig. 1 and 2) is smaller than the thickness of the wiring electrode 30.

The metal film 40 is formed of titanium (Ti), nickel (Ni), chromium (Cr), or the like. The metal film 40 is a film that improves adhesion between the wiring electrode 30 and the metal film 50, and the material of the metal film 40 is appropriately selected according to the material of the wiring electrode 30 and the material of the metal film 50. The metal film 40 corresponds to the "first metal film" of the present invention. Further, titanium (Ti), nickel (Ni), chromium (Cr), or the like forming the metal film 40 corresponds to "first metal particles" of the present invention.

The metal film 50 is formed on the main surface 402 of the metal film 40. The metal film 50 is a flat film and has a main surface 501 and a main surface 502 opposed to each other. The main surface 501 abuts the main surface 402 of the metal film 40. The main surface 502 is a surface of the metal film 50 opposite to the surface in contact with the metal film 40.

The metal film 50 is formed by evaporation, plating, sputtering, or the like. The thickness of the metal film 50 (the length in the first direction in fig. 1 and 2) is smaller than the thickness of the wiring electrode 30.

The metal film 50 is formed of platinum (Pt), gold (Au), or the like. The metal film 50 is a film that is relatively difficult to be oxidized. The metal that is relatively difficult to be oxidized means, for example, a metal classified as being difficult to be oxidized among various metals. That is, depending on the specifications of the electronic component 10, the oxidation difficulty may be in a practical range while the function as the metal film 50 is exerted. The metal film 50 corresponds to the "second metal film" of the present invention. Further, platinum (Pt), gold (Au), or the like forming the metal film 50 corresponds to the "second metal particles" of the present invention. This can suppress oxidation of the surface of the metal film 50 when the UBM80 shown later is formed.

The support frame 60 is formed on the main surface 502 of the metal film 50. The support frame 60 is columnar. The support frame 60 is made of, for example, silicon oxide (SiO)₂) Alumina (Al)₂O₃) Or the like, or synthetic resin such as polyimide, epoxy, or the like.

The cover layer 70 is formed on the surface of the support frame 60 opposite to the surface that contacts the metal film 50. The cover layer 70 is, for example, shaped to cover substantially the entire surface of the electronic component 10 on which the wiring electrodes 30, the metal films 40, and the metal films 50 are formed. The capping layer 70 is made of, for example, alumina (Al)₂O₃) Insulating ceramics such as polyimide, synthetic resin such as epoxy, and lithium tantalate (LiTaO)₃) Lithium niobate (LiNbO)₃) Or piezoelectric material, or semiconductor material such as silicon (Si)And (5) forming the material.

The support frame 60 and the cover layer 70 are formed with through holes 800 that penetrate them in the thickness direction (the first direction in fig. 1). The bottom of the through-hole 800 is realized by the metal film 50.

UBM80 is formed in through-hole 800. The UBM80 is made of nickel (Ni) or copper (Cu), for example. UBM80 is connected to metal film 50 at the bottom of through-hole 800. At least a portion of UBM80 is formed inside support frame 60. The UBM80 corresponds to the "extraction electrode" of the present invention.

Solder balls 81 are formed on the surface of the UBM 80.

In such a configuration, as shown in fig. 1 and 2, a mixed layer 45 is formed on the metal film 40 and the metal film 50. The mixed layer 45 is a layer in which the metal particles P40 forming the metal film 40 and the metal particles P50 forming the metal film 50 are mixed, and for example, satisfies the following conditions.

Fig. 3 is a diagram schematically showing a mixed state of metal particles. As shown in fig. 3, specifically, the mixed layer 45 is a layer in which the mixing ratio of the metal particles P40 forming the metal film 40 and the metal particles P50 forming the metal film 50 is larger than the mixing ratio of the metal particles P40 and the metal particles P50 in the vicinity of the bonding interface between the metal film 40 and the metal film 50 in general. More specifically, the mixing ratio is represented by the mixing ratio (diffusivity) of the metal particles P40 per unit volume in the vicinity of the interface in the metal film 50. Alternatively, the mixing ratio is represented by the mixing ratio (diffusivity) of the metal particles P50 per unit volume in the vicinity of the interface in the metal film 40.

As shown in fig. 3, in the connection electrode of the electronic component 10 of the present embodiment, the mixing ratio is high in the first region Re1 overlapping the bonding surface of the UBM80 and the metal film 50 when viewed in the first direction. In the second region Re2 which is a region not overlapping the junction surface between the UBM80 and the metal film 50, the closer to the first region Re1, the higher the mixing ratio, and the closer to the third region Re3, the lower the mixing ratio. In addition, the third region Re3, which is on the opposite side of the second region Re2 from the first region Re1 when viewed in the second direction of fig. 1 (the direction parallel to the contact surface of the metal film 40 and the metal film 50), in the region not overlapping the bonding surface of the UBM80 and the metal film 50, has a low mixing ratio and is substantially constant.

Therefore, as shown in fig. 1 and 2, in the connection electrode of the electronic component 10 of the present embodiment, the first region Re1 overlaps with the mixed layer 45. That is, at least a part of the mixed layer 45 is formed in the first region Re 1.

With this structure, the mixed layer 45 exists in the current transmission path (main transmission path) directly below the UBM80, that is, from the UBM80 to the wiring electrode 30 via the metal film 50 and the metal film 40. The mixed layer 45 is in a state of so-called metal diffusion, and therefore, the resistivity is low. Therefore, the resistance of the portion connected from UBM80 to wiring electrode 30 via metal film 50 and metal film 40 decreases. Thus, for example, even if the main surface 402 of the metal film 40 is oxidized and the resistance of the connection electrode is increased in the manufacturing process of the electronic component 10, the resistance of the connection electrode can be decreased by the mixed layer 45, and the decrease in the electrical characteristics of the electronic component 10 can be suppressed.

On the other hand, as shown in fig. 3, the third region Re3 does not overlap the mixed layer 45. Specifically, the mixing ratio of the metal particles P40 and the metal particles P50 in the third region Re3 is a fixed value that is much lower than the mixing ratio of the metal particles P40 and the metal particles P50 in the first region Re 1. That is, the mixed layer 45 is not formed in the third region Re 3. The fixed value is "the mixing ratio of the metal particles P40 and the metal particles P50 in the vicinity of the bonding interface between the normal metal film 40 and the metal film 50". Therefore, the mixed layer 45 is not formed in the third region Re3 which is the outer edge portion of the connection electrode, and therefore, a decrease in the bonding strength between the metal film 40 and the metal film 50 can be suppressed.

The mixed layer 45 may be formed in a part of the second region Re 2. For example, in the electronic component 10 shown in fig. 3, the mixing ratio of the region close to the first region Re1 among the second region Re2 is higher than that of the third region Re3 and is about the same as that of the first region Re1, and thus it can be said that the mixed layer 45 is formed in a part of the second region Re 2. In this case, the region where the mixed layer 45 is formed in the second region Re2 is preferably smaller than the region where the mixed layer 45 is formed in the first region Re 1. Note that if the objects of comparison are the same in the first region Re1 and the second region Re2, the region where the mixed layer 45 is formed may be a planar region (area) or a cubic region (volume). In this case, the region in which the mixed layer 45 is formed is smaller than the region in which the mixed layer 45 is not formed, whereby the bonding strength between the metal film 40 and the metal film 50 can be suppressed from decreasing.

At this time, it is more preferable to form the mixed layer 45 continuously so as to span the first region Re1 and the second region Re 2. In this case, since a region in which the resistance is reduced continuously exists in the current transmission path, the degradation of the electrical characteristics can be further suppressed.

In the second region Re2, the mixed layer 45 may not be formed at all. That is, the blending ratio of the second region Re2 may be maintained at a value that is approximately the same as the blending ratio of the third region Re 3. In this case, the region in which the mixed layer 45 is formed in the metal film 40 and the metal film 50 is limited to the first region Re1 that is the central portion of the connection electrode, and therefore, the decrease in the bonding strength between the metal film 40 and the metal film 50 can be further suppressed.

As shown in fig. 1 and 3, the second region Re2 may overlap the support frame 60 in a region that does not overlap the bonding surface of the UBM80 and the metal film 50 when viewed in the first direction of fig. 1, and the third region Re3 may overlap the support frame 60 in a region that does not overlap the bonding surface of the UBM80 and the metal film 50.

The mixed layer 45 is formed by locally heating the metal film 40 and the metal film 50. For example, as described later with reference to (a), (B), and (C) of fig. 4 and 5, the hybrid layer 45 is formed on the metal film 40 and the metal film 50 by irradiating a through hole in which the UBM80 is formed with a laser or the like.

At this time, of the regions in the metal film 40 and the metal film 50, a region overlapping the support frame 60 having at least a part of the UBM80 therein is located at a relatively short distance from the region heated by the laser light when viewed in the first direction. Therefore, the mixed layer is easily affected by laser heating. Therefore, if the region in which the mixed layer is easily formed is set to the second region Re2, the connection electrode exhibiting the effect of the present invention can be more easily obtained.

On the other hand, since the region that does not overlap the support frame 60 is located at a relatively long distance from the region heated by the laser beam when viewed in the first direction, the region is less likely to be affected by the laser beam heating. Therefore, if this region in which the mixed layer is difficult to form is set as the third region Re3, a connection electrode exhibiting the effects of the present invention can be obtained more easily.

As shown in fig. 1 and 2, the mixed layer 45 preferably does not reach the main surface 502 of the metal film 50. As described above, since the metal film 50 is a film that is difficult to oxidize, an increase in resistivity due to oxidation during the manufacturing process is difficult to occur. Therefore, even if the mixed layer 45 does not reach the main surface 502 of the metal film 50, the resistance of the portion connected to the wiring electrode 30 from the UBM80 through the metal film 50 and the metal film 40 is not likely to increase. Further, by not providing the mixed layer 45 on the main surface 502 of the metal film 50, that is, on the bonding surface between the metal film 50 and the UBM80, it is possible to suppress a decrease in bonding strength between the metal film 50 and the UBM 80. This improves the reliability of the bonding between the metal film 50 and the UBM 80.

As shown in fig. 1 and 2, the mixed layer 45 preferably does not reach the main surface 401 of the metal film 40. That is, the mixed layer 45 is preferably not present at the bonding surface between the metal film 40 and the wiring electrode 30. This can suppress a decrease in the bonding strength between the metal film 40 and the wiring electrode 30. Therefore, the reliability of the bonding of the metal film 40 and the wiring electrode 30 is improved.

The mixed layer 45 may reach the wiring electrode 30. In this case, the resistance of the portion connected to the wiring electrode 30 from the UBM80 through the metal film 50 and the metal film 40 is reduced, and the electrical characteristics of the electronic component 10 can be improved. At this time, the mixed layer 45 is preferably not present in a region overlapping with the second region Re2 described above at the bonding interface between the metal film 40 and the wiring electrode 30. With this structure, a decrease in the bonding strength between the wiring electrode 30 and the metal film 40 can be suppressed.

In the above description, as shown in fig. 1 and 2, the mixed layer 45 is shown as overlapping the entire first region Re1, but the resistance can be reduced as long as the mixed layer 45 overlaps at least a part of the first region Re 1.

The connection electrode of the electronic component 10 can be manufactured by the following method. Fig. 4 is a flowchart illustrating a method of manufacturing a connection electrode according to an embodiment of the present invention. Fig. 5 (a), (B), and (C) are diagrams showing respective states of the manufacturing process of the connection electrode. The following describes the manufacturing method with reference to the flowchart of fig. 4.

The metal film 40 is formed on the main surface 302 of the wiring electrode 30 by vapor deposition, plating, sputtering, or the like (S11). Next, the metal film 50 is formed on the main surface 402 of the metal film 40 by vapor deposition, plating, sputtering, or the like (S12). Next, the support frame 60 as an insulating layer is formed on the main surface 502 of the metal film 50, and the cover layer 70 is further formed (S13).

Next, as shown in fig. 5 (a), the laser 900 irradiates laser light from the surface of the cover layer 70 opposite to the surface in contact with the support frame 60. The energy of the laser is set for grinding the cover layer 70 and the support frame 60. By continuing the laser irradiation of the laser beam to the cover 70 by the laser 900, the cover 70 and the support frame 60 are ground. Thereby, the through-hole 800 penetrating the cover layer 70 and the support frame 60 is formed as shown in fig. 5B (S14).

Then, as shown in fig. 5 (B), in this state, the main surface 502 of the metal film 50 is exposed at the bottom of the through hole 800.

In this state, the laser 900 irradiates laser light toward the metal film 50, thereby locally heating the vicinity of the contact surface between the metal film 50 and the metal film 40. The energy of the laser beam at this time is set so that the vicinity of the contact surface between the metal film 50 and the metal film 40 becomes a predetermined temperature. The energy for the local heating may be the same as the energy for forming the through-hole 800 described above. By continuing the irradiation of the laser light for a predetermined time, the mixed layer 45 is formed so as to include the contact surface between the metal film 50 and the metal film 40 (S15). As described above, the mixed layer 45 is a layer in which the metal particles P50 of the metal film 50 and the metal particles P40 of the metal film 40 are mixed more than in the usual stacked state of the metal film 50 and the metal film 40.

Next, as shown in fig. 5C, the UBM80 is formed in the through-hole 800 (S16).

In such a manufacturing method, a laser for forming the through hole 800 for UBM80 can be used for forming the mixed layer 45. Therefore, the manufacturing process can be simplified. In particular, the energy for local heating is set to be the same as the energy for forming the through-hole 800, thereby further simplifying the manufacturing process.

In fig. 1 to 3, the electronic component 10 is shown in which two metal films are stacked on the wiring electrode, but the number of metal films stacked on the wiring electrode is not limited to two, and may be three or more. In this case, if a mixed layer is formed at least between the metal film closest to the extraction electrode (for example, UBM80 described above) and the metal film in contact with the closest metal film, an effect is obtained that the resistance can be reduced and deterioration of the electrical characteristics can be suppressed.

As shown in fig. 6, one metal film may be formed on the wiring electrode. Fig. 6 is a side sectional view showing an example of a derivative of the structure of the connection electrode according to the embodiment of the present invention.

The electronic component 10A shown in fig. 6 differs from the electronic component 10 shown in fig. 1 in that the metal film 40 to be the adhesion layer is omitted and the mixed layer 35 is formed at a different position. The other structure of the electronic component 10A is the same as that of the electronic component 10, and the description of the same parts is omitted.

As shown in fig. 6, in the electronic component 10A, the metal film 50 is formed on the main surface 302 of the wiring electrode 30. That is, the main surface 501 of the metal film 50 abuts the main surface 302 of the wiring electrode 30.

The mixed layer 35 is formed on the metal film 50 and the wiring electrode 30. At this time, the mixed layer 35 is formed including the bonding interface between the metal film 50 and the wiring electrode 30. The mixed layer 35 is a layer in which metal particles (corresponding to "third metal particles" in the present invention) forming the wiring electrode 30 are mixed with metal particles forming the metal film 50, and the condition of the mixed layer 35 is the same as the case where the metal particles of the metal film 40 in the condition of the mixed layer 45 described above are replaced with the metal particles of the wiring electrode 30.

The mixed layer 35 overlaps with the first region Re 1. More specifically, at least a part of the mixed layer 35 is formed in the first region Re1 overlapping with the junction surface of the UBM80 and the metal film 50.

Even when the metal film 50 is directly laminated on the wiring electrode 30, there is a possibility that a main surface of the wiring electrode 30 on the metal film 50 side is oxidized to increase the resistance, and the electrical characteristics of the electronic component 10A including the wiring electrode 30 are deteriorated. However, as in the electronic component 10A, the mixed layer 35 is formed between the wiring electrode 30 and the metal film 50, whereby the effects of reducing the resistance and suppressing the deterioration of the electrical characteristics are obtained.

Description of the reference numerals

10. 10A: an electronic component;

20: a substrate;

30: a wiring electrode;

40. 50: a metal film;

35. 45, and (2) 45: a mixed layer;

60: a support frame;

70: a cover layer;

80: under Bump Metallurgy (UBM);

81: a solder ball;

201. 301, 302, 401, 402, 501, 502: a main face;

800: a through hole;

900: a laser;

p40, P50: metal particles;

re 1: a first region;

re 2: a second region.