JP2015167222A - Electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part that can make sure the conduction from an electronic device to an external electrode while keeping air-tightness of the inside of a cavity, and keep the characteristic of the electronic device excellent.SOLUTION: An electronic part having an electronic device encapsulated in a cavity has an extraction electrode which is electrically connected to a mount electrode. The extraction electrode is formed at the cavity-side portion from a joint film at the outside of the cavity, and surrounds an opening portion at the joint face side of a through-hole, and joins a first substrate and a second substrate. The extraction electrode includes a mount electrode connection portion which is electrically connected to the mount electrode, and an external electrode connection portion which covers the opening portion of the through-hole and connects the external electrode and the mount electrode connection portion.

Description

  The present invention relates to an electronic component for sealing an electronic device.

  2. Description of the Related Art Conventionally, many surface mount electronic components have been used in mobile phones and portable information terminal devices. Among these, electronic components such as a crystal resonator, MEMS (Micro-Electro-Mechanical-Systems), gyro sensor, and acceleration sensor form a cavity inside a package composed of a base substrate and a lid substrate, and an electron is formed in the cavity. It is formed by enclosing and sealing the device (see Patent Document 1).

  This package has an extraction electrode around the opening of the through hole formed in the base substrate. The lead electrode is electrically connected to an external electrode formed inside the through hole. Thereby, the circumference | surroundings of the opening part of the through-hole formed in the exterior of a cavity are sealed among a base substrate and a lid substrate. For this reason, the airtightness of the cavity is maintained.

Japanese Patent No. 5134357

  However, the conventional package structure has a problem. The lead electrode of the package is formed by patterning a conductive material on the upper surface of the base substrate. On the other hand, the external electrode is formed by closing the inside of the through hole with a conductive material from the lower surface side of the base substrate. In this case, it is necessary to connect the extraction electrode and the external electrode at the opening end of the through hole. However, in such a structure, since it is difficult to connect the extraction electrode and the external electrode at the opening end of the through hole, there is a problem in that it is difficult to establish conduction between the two electrodes and disconnection occurs. Further, when the conductive material for the lead electrode is patterned by a process such as etching, the conductive material around the opening of the through hole may be removed. In addition, since the conductive material is formed in the through hole from the lower surface side of the base, it is difficult to form the external electrode up to the periphery of the opening portion of the through hole on the upper surface of the base substrate. In this state, even if the external electrode is formed inside the through hole, it is difficult to establish conduction between the two electrodes because the extraction electrode is not formed up to the opening end of the through hole. This prevents the electronic device from functioning.

  An electronic component according to the present invention is sealed in a first substrate, a second substrate bonded to the first substrate, and forming a cavity between the first substrate and the cavity. An electronic device comprising: an electronic device comprising: an electronic device comprising: an electronic device comprising: an electronic device including: a first substrate and a second substrate disposed outside the cavity in a circumferential direction between the bonding surfaces of the first substrate and the second substrate. A bonding film that bonds the substrate, and is located outside the cavity in the circumferential direction and penetrates from the bonding surface of one of the first substrate and the second substrate to a surface facing the bonding surface. A through-hole, an external electrode composed of a metal film formed from an inner surface of the through-hole to a surface facing the bonding surface of the one substrate, an electronic device formed inside the cavity, and Mounted power that is electrically connected And an extraction electrode electrically connected to the mount electrode, and the extraction electrode surrounds the periphery of the opening on the joint surface side of the through hole, and the first substrate and the second substrate And an external electrode connection part that covers the opening of the through hole and is connected to the external electrode and the mount electrode connection part, It is characterized by having.

  According to the present invention, the mount electrode connecting portion joins the first substrate and the second substrate, and the external electrode connecting portion covers the opening of the through hole. Therefore, the mount electrode and the external electrode can be reliably conducted while maintaining the airtightness of the cavity. Accordingly, since electrical conduction from the electronic device to the external electrode can be ensured while maintaining airtightness inside the cavity, it is possible to provide an electronic component that maintains good characteristics of the electronic device.

The external electrode may further include a sealing portion that fills the inside of the through hole.
The sealing portion may include a coating film that is also stacked on an upper layer of a metal film formed on a surface facing the bonding surface, and covers the sealing portion stacked on the upper layer of the metal film. .
The mount electrode connecting portion may be formed of a metal that anodically bonds the first substrate and the second substrate.

The external electrode connection portion may be formed of a metal having higher corrosion resistance than the mount electrode connection portion.
The mount electrode connecting portion may be formed of a metal capable of eutectic bonding or metal diffusion bonding between the first substrate and the second substrate.

  According to the present invention, since electrical conduction from an electronic device to an external electrode can be ensured while maintaining airtightness inside the cavity, it is possible to provide an electronic component that maintains good characteristics of the electronic device.

It is an external appearance perspective view which shows an example of the electronic component by one Embodiment of this invention. It is an internal block diagram of the electronic component shown in FIG. 1, Comprising: It is the figure seen from the 2nd board | substrate side. It is a cross-sectional arrow view of the AA line shown in FIG. It is a disassembled perspective view of the electronic component shown in FIG. It is a flowchart for demonstrating the manufacturing process of the electronic component shown in FIG. It is sectional drawing which shows the manufacturing method of the electronic component shown in FIG. It is sectional drawing which shows the manufacturing method of the electronic component shown in FIG. It is an internal block diagram of another example (modification example 1) of the electronic component by one Embodiment of this invention, Comprising: It is the figure seen from the 2nd board | substrate side. It is a cross-sectional arrow view of the BB line shown in FIG. It is a cross-sectional arrow view of another example (modification 2) of the electronic component according to the embodiment of the present invention. It is a cross-sectional arrow figure of another example (modification 3) of the electronic component by one Embodiment of this invention. It is a cross-sectional arrow figure of another example (modification 3) of the electronic component by one Embodiment of this invention. It is a disassembled perspective view of another example (modification 4) of the electronic component by one Embodiment of this invention. FIG. 14 is a cross-sectional view of the electronic component shown in FIG. 13. It is a flowchart for demonstrating the manufacturing process of the electronic component shown in FIG. FIG. 17 is a cross-sectional view for illustrating a manufacturing step for the electronic component shown in FIG. 16. FIG. 14 is a cross-sectional view for explaining a manufacturing step for the electronic component shown in FIG. 13.

(First embodiment)
Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. 1 to 4.
"Configuration of electronic components"
FIG. 1 is an external perspective view showing an example of an electronic component according to an embodiment of the present invention. FIG. 2 is an internal configuration diagram of the electronic component shown in FIG. 1 and is a diagram seen from the second substrate side. 3 is a cross-sectional view taken along line AA shown in FIG. FIG. 4 is an exploded perspective view of the electronic component shown in FIG.

  As shown in FIGS. 1 to 4, the electronic component 1 of the present embodiment is formed in a two-layer structure with a first substrate 2 and a second substrate 3, and the electronic device 4 is placed inside the cavity C. This is a packaged surface mount package.

  That is, the electronic component 1 is bonded to the first substrate 2, the second substrate 3 bonded to the first substrate 2, and forming a cavity C between the first substrate 2 and the inside of the cavity C. Electronic device 4 to be stopped. The electronic component 1 is disposed between the bonding surfaces of the first substrate 2 and the second substrate 3 outside the cavity C, and the bonding film 10 that bonds the first substrate 2 and the second substrate 3 together. Have Further, the electronic component 1 is located on the cavity C side from the bonding film 10 outside the cavity C, and from the bonding surface of one of the first substrate 2 and the second substrate 3 to the surface opposite to the bonding surface. It has a through-hole 11 (12, 13, 14) that penetrates. In addition, the electronic component 1 has an external electrode 15 (16, 17, 18) composed of a metal film formed from the inner surface of the through hole 11 (12, 13, 14) to the surface opposite to the bonding surface of one substrate. ). In addition, the electronic component 1 includes a mount electrode 5 (6, 7, 8) that is formed inside the cavity C and is electrically connected to the electronic device 4. In addition, the electronic component 1 includes lead electrodes 27 (28, 29, 30) that are electrically connected to the mount electrodes 5 (6, 7, 8). In addition, the extraction electrode 27 (28, 29, 30) is formed in a portion closer to the cavity C than the bonding film 10 outside the cavity C, and the opening on the bonding surface side of the through hole 11 (12, 13, 14) is formed. A mounting electrode connecting portion 19 (20, 21, 22) that encloses and joins the first substrate 2 and the second substrate 3 and is electrically connected to the mounting electrode 5 (6, 7, 8); The external electrode connection part 23 (24, 25, 26) which covers the opening part of a hole and connects with the external electrode 15 (16, 17, 18) and the mount electrode connection part 19 (20, 21, 22) is provided.

  The first substrate 2 is made of a glass material, for example, an insulating substrate such as borosilicate glass, soda glass, or ceramic, or a silicon substrate that has been locally subjected to insulation separation processing. The first substrate 2 is formed in a plate shape with a size that can be superimposed on the second substrate 3.

  The second substrate 3 is formed in a plate shape and is made of a glass material, for example, an insulating substrate such as borosilicate glass, soda glass, or ceramic, or a silicon substrate subjected to local insulation separation processing. A concave portion 9 having a rectangular shape in a top view in which the electronic device 4 is accommodated is formed on the bonding surface side of the second substrate 3 to which the first substrate 2 is bonded. The concave portion 9 becomes a cavity C that accommodates the electronic device 4 when the substrates 2 and 3 are overlapped.

  In the present embodiment, the case where the concave portion 9 is formed on the second substrate 3 side will be described as an example. However, the concave portion 9 may be formed on the first substrate 2 side. It may be formed in 2, 3 respectively.

The electronic device 4 includes, for example, at least one or more of a piezoelectric vibrating piece, a light receiving element, a light emitting element, an acceleration sensor, a MEMS, and other elements.
The bonding film 10 is formed and patterned outside the cavity C on the same surface as the cavity C of the second substrate 3. The bonding film 10 is formed in an annular shape along the periphery of the bonding surface of the second substrate 3 so as to surround the cavity C. The bonding film 10 described above is formed of, for example, aluminum (Al), gold tin alloy (AuSn), gold tantalum (AuTa), or the like. Thereby, the bonding film 10 can bond the first substrate 2 and the second substrate 3 by processes such as anodic bonding, gold-tin bonding, and metal diffusion bonding. In the present embodiment, a case where an electronic component is manufactured by anodic bonding using aluminum (Al) in an “electronic component manufacturing method” described later will be described as an example.

  In the present embodiment, the through holes are configured by four through holes 11, 12, 13, and 14. Each through hole is located outside the cavity C and is located closer to the cavity C than the bonding film 10. Each through-hole penetrates from the bonding surface of the first substrate 2 to the opposite surface. Each through hole is formed in a portion surrounded by the bonding film 10. The external electrodes 15, 16, 17, and 18 are formed from the inner surface of the through holes 11, 12, 13, and 14 to the surface opposite to the bonding surface of the first substrate 2, respectively. In the present embodiment, each external electrode is formed up to the periphery of each through hole on the surface opposite to the bonding surface of the first substrate 2. In addition, the external electrode has conductivity and is formed by sputtering, plating, or a laminated structure of conductive resin material so that sufficient strength can be obtained when connected to the electronic circuit board by solder or the like. Is preferred.

  The mount electrodes 5, 6, 7, and 8 are formed inside the cavity C and are electrically connected to the electronic device 4. Each mount electrode is formed on the bonding surface of the first substrate 2 and patterned. Moreover, each mount electrode mounts the electronic device 4 via a conductive adhesive, a gold bump, a wire, or the like. Each mount electrode only needs to be formed on the substrate on which the electronic device 4 is mounted out of both substrates, and does not necessarily have to be formed on the first substrate 2.

  The lead electrodes 27, 28, 29, and 30 are electrically connected to the mount electrodes 5, 6, 7, and 8, respectively. The lead electrodes 27, 28, 29, and 30 are formed on the bonding surfaces of the bonding surfaces of the first substrate 2 and the second substrate 3. In the present embodiment, each extraction electrode is formed on the second substrate 3 and patterned. The lead electrodes 27, 28, 29, 30 are composed of mount electrode connecting portions 19, 20, 21, 22 and external electrode connecting portions 23, 24, 25, 26, respectively.

  The mount electrode connecting portions 19, 20, 21, and 22 surround the openings on the bonding surface side of the through holes 11, 12, 13, and 14, respectively. Each mount electrode connecting portion joins the first substrate 2 and the second substrate 3. The mount electrode connecting portions 19, 20, 21, and 22 are electrically connected to the mount electrodes 5, 6, 7, and 8, respectively.

  Further, the external electrode connection portions 23, 24, 25, and 26 cover the openings on the bonding surface side of the through holes 11, 12, 13, and 14, respectively. The external electrode connection parts 23, 24, 25, and 26 are connected to the external electrodes 15, 16, 17, and 18, respectively. The external electrode connection portions 23, 24, 25, and 26 are connected to the mount electrode connection portions 19, 20, 21, and 22, respectively.

  In the present embodiment, each external electrode covers from the inner side surface of each through-hole to the surface opposite to the surface on the second substrate 3 side of each external electrode connection portion. Thereby, further, each external electrode and each mount electrode are reliably conducted. In addition, not only this embodiment but each external electrode should just be formed in the inner surface of each through-hole, and should be connected with each external electrode connection part.

  In this embodiment, the mount electrode connection portion and the external electrode connection portion are formed of the same material, but the external electrode connection portions 23, 24, 25, and 26 are openings of the through holes 11, 12, 13, and 14. As long as the portion is covered, it may be formed of another material.

  Further, in the present embodiment, the extraction electrode is entirely formed on the opposite substrate, not the substrate on which the through hole is formed. This eliminates the need to form the mount electrode connection portion and the external electrode connection portion on separate substrates. However, the lead electrode does not necessarily have to be formed entirely on a substrate different from the substrate on which the through hole is formed, and at least the external electrode connection portion facing the through hole is formed on a substrate different from the substrate on which the through hole is formed. It only has to be done.

  In the present embodiment, the case where the mount electrode includes four terminals will be described as an example. However, the mount electrode may be increased or decreased according to the number of electrode terminals required for the electronic device 4. In this case, the number of electrodes increases / decreases according to the number of terminals of the mount electrode.

  Moreover, in this embodiment, all the external electrodes are formed on the inner surface of the through hole, but the present invention is not limited to this. For example, one external electrode may be connected to a routing electrode that is routed from the mount electrode to the end of the bonding surface of both substrates. In this case, a part of the routing electrode may constitute a bonding film.

The first substrate 2 and the second substrate 3 are bonded by the bonding film 10 and each mount electrode connecting portion. That is, the bonding film 10 surrounds the first substrate 2 and the second substrate 3 along the periphery of the second substrate 3, and the inside thereof is firmly adhered by bonding. In addition, the periphery of the opening of each through hole formed in the first substrate 2 is bonded to the second substrate 3 by each mount electrode connecting portion, and is firmly adhered. Since the inside of the joint part that is firmly adhered is kept airtight, the inside of the package including the cavity C is kept airtight.
Furthermore, since the through electrode connecting portion covers the opening of the through hole, the external electrode can be reliably connected to the through electrode connecting portion.

"Manufacturing method of electronic parts"
Next, a method for manufacturing an electronic component in the above-described embodiment will be described with reference to FIGS. FIG. 5 is a flowchart showing a method of manufacturing the electronic component shown in FIG. 6 and 7 are cross-sectional views showing respective steps of the method of manufacturing the electronic component shown in FIG. The cross-sectional views shown in FIGS. 6 and 7 are views showing the same cross section as the cross section taken along the line AA in FIG. In this embodiment, a plurality of electronic components are collectively formed on the wafer.

First, the formation process of the first substrate 2 will be described (S100). In the present embodiment, the first substrate 2 is formed of a glass material.
First, after polishing and cleaning the first substrate 2 to a predetermined thickness, polishing, cleaning, and etching steps are performed to remove the outermost processed layer by etching or the like (S1). FIG. 6 (S1) is a view showing a part of the first substrate 2 subjected to the polishing, cleaning, and etching steps.

  Next, a through hole forming step for forming the through holes 11, 12, 13, and 14 at predetermined positions on the first substrate 2 is performed (S2). In the through hole forming step, the first substrate 2 is masked with a dry film, a photoresist, or the like except for the through hole, and the unmasked portion is removed by blasting or etching. Thereafter, the mask is removed, and the processed portion is formed by cleaning. Thereby, each through-hole is formed. FIG. 6 (S <b> 2) is a view in which each through hole is formed in the first substrate 2.

  Next, a mount electrode forming step for forming the mount electrodes 5, 6, 7, and 8 at predetermined positions on the first substrate 2 is performed (S3). Each mount electrode is formed, for example, by forming a laminated structure of chromium (Cr) and gold (Au) by sputtering or the like. FIG. 6 (S <b> 3) is a diagram in which mount electrodes 5, 6, 7, and 8 are formed at predetermined positions on the first substrate 2.

  Next, a mounting step of mounting the electronic device 4 on the formed mount electrodes 5, 6, 7, and 8 is performed (S4). In the present embodiment, an electrode connection portion formed by a gold (Au) bump is formed on the mount electrode. Then, the electrode portion of the electronic device 4 and the gold (Au) bump are bonded by ultrasonic bonding. Thereby, the electronic device 4 is mounted on each mount electrode. FIG. 6 (S4) is a diagram in which the electronic device 4 is mounted on each mount electrode.

Next, the formation process of the second substrate 3 will be described (S200). In the present embodiment, the second substrate 3 is formed of a glass material.
First, after polishing and cleaning the second substrate 3 to a predetermined thickness, polishing, cleaning, and etching steps are performed to remove the outermost processed layer by etching or the like (S5). FIG. 6 (S5) is a diagram showing a part of the second substrate 3 subjected to the polishing, cleaning, and etching steps. Next, a recess forming step for forming the recess 9 in the second substrate 3 is performed (S6). In the recess forming step, the second substrate 3 is masked with a dry film, a photoresist or the like except for the recess, and the unmasked portion is removed by blasting or etching. Thereafter, the mask is removed, and the processed part is washed. Thereby, the recessed part 9 is formed. The recess 9 is for forming the cavity C. FIG. 6 (S <b> 6) is a diagram in which the concave portion 9 is formed in the second substrate 3.

  Next, a bonding film forming step for forming the bonding film 10 at a predetermined position on the surface of the second substrate 3 on which the recess 9 is formed is performed (S7). The bonding film 10 is formed at a position separated from the recess 9 of the second substrate 3. In this embodiment, an aluminum (Al) film is deposited on the surface of the second substrate 3 on which the concave portion 9 is formed by sputtering, and then a portion corresponding to the bonding film is masked with a photoresist, and an unmasked portion is masked. Remove by etching. Thereby, the bonding film 10 is formed. FIG. 6 (S <b> 7) is a diagram in which the bonding film 10 is formed on the second substrate 3.

  Next, a lead electrode forming step for forming lead electrodes 27, 28, 29, and 30 is performed (S8). In the extraction electrode forming step, in this embodiment, an aluminum (Al) film is deposited on the surface of the second substrate 3 on which the bonding film 10 is formed by sputtering, and then a portion corresponding to the extraction electrode is masked with a photoresist. The unmasked portion is removed by etching. Thereby, an extraction electrode is formed. The extraction electrode is formed between the bonding film 10 and the recess 9 on the surface of the second substrate 3 on which the bonding film 10 is formed. FIG. 6 (S <b> 8) is a diagram in which each extraction electrode is formed on the second substrate 3.

In this embodiment, the first substrate 2 and the second substrate 3 are bonded by anodic bonding using the bonding film 10 and the mount electrode connecting portion of each extraction electrode. Therefore, in the lead electrode forming step, the bonding film 10 and each mount electrode connecting portion are processed so as to be electrically connected. For example, in the extraction electrode forming step, a connection portion that connects the extraction electrode and the bonding film is formed together with the extraction electrode. Note that the bonding film forming step and the extraction electrode forming step may be performed in the same step. At this time, the connection portion is also formed at the same time.
Further, when each mount electrode connecting portion and each external electrode connecting portion are formed of different materials, they are formed separately in the extraction electrode forming step.

Next, a bonding step of sealing the electronic device by bonding the first substrate 2 and the second substrate 3 is performed (S9). FIG. 7 (S9) is a diagram showing a joining process. In the bonding process, in this embodiment, the first substrate 2 and the second substrate 3 are aligned, and then both the substrates are brought into close contact with each other. At this time, as shown in FIG. 7 (S9), a part of each mount electrode connection part and a part of each mount electrode are overlapped and connected outside the recess 9 of the second substrate. In addition, as shown in FIG. 3, each mount electrode has a part which overlaps with each mount electrode connection part. The portion that overlaps with each of the mount electrode connection portions is formed to have a smaller width than the portion on which the electronic device is mounted in plan view. If the portion connected to each mount electrode connecting portion and each mount electrode connecting portion overlap, a step may be generated between the overlapping portion on the mount electrode connecting portion side and another portion. If it is a structure as shown in FIG. 4, the overlapping part of both will become small and it can electrically connect reliably.
At this time, since the external electrode connection portion is formed on the second substrate, the external electrode connection portion can also be formed at a position facing the opening of the through hole.

  Thereafter, the substrate is heated in a vacuum chamber, an anode is disposed on the bonding film 10, and a cathode 31 such as carbon or stainless steel is disposed on the first substrate 2. Thereby, a voltage is applied between an anode and a cathode, and anodic bonding is performed. By performing anodic bonding, the first substrate 2 is bonded to the bonding film 10, and the mount electrode connecting portions around the through holes 11, 12, 13, and 14 are bonded. Therefore, the inside of the cavity C is sealed. Due to the processing in vacuum, the internal cavity is kept at a vacuum level.

  Next, an external electrode forming step for forming the external electrodes 15, 16, 17, and 18 on the first substrate 2 is performed (S10). Each external electrode is formed so as to cover the inner surface of each through-hole formed in the first substrate 2 and each external electrode connection portion formed in the second substrate 3. In this embodiment, first, a base film having a laminated structure of chromium (Cr) and nickel (Ni) is formed by sputtering or the like, and then a nickel (Ni) plating film of about 2 to 5 μm is formed on the base film. Finally, in order to improve solder wettability on the nickel plating film, gold (Au) or the like is thinly plated. Thereby, each external electrode is formed. FIG. 7 (S 10) is a diagram in which external electrodes are formed on the first substrate 2.

Next, a cutting process for cutting both substrates is performed (S11). In this embodiment, dicing is performed according to the size of the electronic component, and the electronic component is separated into individual pieces.
Finally, an inspection process for inspecting the appearance and electrical characteristics of the electronic component is performed (S12). Thereby, an electronic component is formed. FIG. 7 (S11) is a diagram illustrating an electronic component separated into pieces.

  As described above, according to the electronic component 1 and the method for manufacturing the electronic component 1 according to the present embodiment, the mount electrode connecting portion joins the first substrate and the second substrate, and the external electrode connecting portion is an opening of the through hole. The structure is covered. Therefore, the mount electrode and the external electrode can be reliably conducted while maintaining the airtightness of the cavity. Accordingly, since electrical conduction from the electronic device to the external electrode can be ensured while maintaining airtightness inside the cavity, it is possible to provide an electronic component that maintains good characteristics of the electronic device.

  In addition, each mount electrode connecting portion is formed of a metal that anodically bonds the first substrate 2 and the second substrate 3. Thereby, each mount electrode connection part can perform anodic bonding between the first substrate 2 and the second substrate 3. For this reason, the first substrate 2 and the second substrate 3 can be sealed by bonding the outside of the cavity C with the bonding film 10, and the periphery of each through hole is bonded by each mount electrode connecting portion. It can be sealed. Therefore, since airtightness inside the cavity C can be reliably maintained, the characteristics of the electronic device 4 sealed inside the cavity C can be kept stable.

  In the lead electrode forming step S8, the connection portion is not necessarily formed. In this case, for example, joining by each mount electrode connection part can be performed by contacting each extraction electrode with an electrode probe or the like and directly applying a voltage.

  In addition, although explanation is omitted in the above-mentioned “manufacturing method of electronic component”, when the connecting portion is formed in the lead electrode forming step S8, after performing the joining step S9 and before performing the external electrode forming step S10, A connecting portion removing step for removing the connecting portion is performed. When either of the two substrates is formed of a glass material, the connection portion removing step is realized by, for example, irradiating laser light from the outside toward a portion where the connection portion is located. Then, the laser beam passes through this substrate and is irradiated to the connection portion. Thereby, the connection portion is removed, and the bonding film and the extraction electrode are electrically insulated. Note that it is not necessary to completely remove the connection portion as long as the bonding film and the extraction electrode are electrically insulated from each other.

  Further, when anodic bonding is used in the bonding process, each external electrode connecting portion may be formed of a metal having corrosion resistance than each mount electrode connecting portion. For example, each external electrode connection portion is formed of a single layer of silicon or a stack of silicon and chromium.

  Since each external electrode connection part covers the opening part of each through-hole, it is a part which is more easily exposed to an external environment. In the case of this configuration, each mount electrode connecting portion can be made less likely to be corroded through the opening of the through hole by each external electrode connecting portion having corrosion resistance. Therefore, it is possible to prevent the deterioration of the characteristics of the electronic component due to leakage or the like.

  Further, the bonding film may not be a conductor as long as it is not a bonding step by anodic bonding, and both substrates may be bonded. For example, the bonding film may be formed of a resin or the like. In addition, the mount electrode connecting portion may be formed of a conductor while being bonded to both substrates.

(Modification 1)
In the first embodiment, the case where the through hole is formed on the first substrate 2 side has been described as an example. However, it may be formed on the second substrate 3 side. 8 and 9 are diagrams showing another example of the electronic component (electronic component according to Modification 1). Note that the description of the same configuration as in FIGS. 1 to 4 is omitted. FIG. 8 is an internal configuration diagram of another example of the electronic component according to the embodiment of the present invention, as viewed from the second substrate side. 9 is a cross-sectional view taken along line BB shown in FIG.

  In the electronic component according to the first modification, no through hole is formed on the first substrate 2 side. Therefore, as shown in FIG. 9, each mount electrode connecting portion 19 (20, 21, 22) is provided on the first substrate 2. Formed on the joint surface. Furthermore, the entire extraction electrode 27 (28, 29, 30) including the external electrode connection portion 23 (24, 25, 26) can be formed on the bonding surface of the first substrate 2. Further, the bonding film 10 can also be formed on the bonding surface of the first substrate 2. In this case, in the mount electrode forming step according to S3 in FIG. 6, in addition to each mount electrode 19, the bonding film 10 and the extraction electrode 27 can be simultaneously formed on the first substrate 2. The bonding film forming step and the extraction electrode forming step according to S8 can be omitted.

  Further, each through hole is formed outside the circumferential direction of the concave portion 9 of the second substrate 3. Furthermore, each external electrode is formed from the inner surface of each through hole of the second substrate 3 to the surface opposite to the bonding surface of the second substrate 3. At this time, in the first modification, each external electrode 15 (16, 17, 18) is provided on the inner wall of the through hole 11 (12, 13, 14) and on the first substrate 2 side of each external electrode connection portion. The surface opposite to the surface is covered with a plating film. However, since each external electrode only needs to be connected to each external electrode connection portion, it does not have to be formed on the surface opposite to the surface on the first substrate 2 side of each external electrode connection portion.

  As described above, according to the electronic component 1 according to the present modification, the mount electrode, the bonding film, and the extraction electrode are provided on the same surface of the second substrate 3 as compared with the electronic component of the first embodiment shown in FIGS. Since it can form, these can be formed easily.

(Modification 2)
In the first modification, each external electrode is configured to cover only the inner wall of the through hole. However, as in the second modification, the external electrode may further include a sealing portion that fills the inside of the through hole. FIG. 10 is a cross-sectional arrow view of another example of an electronic component according to an embodiment of the present invention.

In this modification, as shown in FIG. 10, each external electrode is a plated film made of a nickel film formed from the inner surface of each through-hole to the surface opposite to the bonding surface of the second substrate 3 (opposing surface). 33 and a sealing portion 31 that covers the plating film 33 and seals the inside of each through hole. Moreover, in this modification, the plating film 33 covers the surface opposite to the surface on the first substrate 2 side of the external electrode connection portion.
The plating film 33 is formed of an electroless nickel plating film having a thickness of about 2 μm along the through hole 11.

Further, the sealing portion 31 is formed by filling the inside of the through hole with a conductive resin mainly composed of silver paste so as to cover the plating film 33.
Thereby, when using a brittle material like a glass substrate for a board | substrate, the stress concerning each board | substrate can be reduced by filling the inside of a through-hole with the sealing part 31. FIG. Moreover, since the covering property inside a through-hole can be improved, environmental resistance can be improved.

  Further, when each external electrode is mounted on a circuit board or the like by soldering, it forms a eutectic with solder and is firmly bonded. At this time, a strong stress is applied to the substrate, and the package may crack from the through hole. By providing a sealing part that fills the inside of the through-hole, the effect of cracking due to stress is suppressed, and the sealing part keeps the airtight and prevents the entry of moisture etc. from the outside to prevent corrosion of the external electrode connection part. It can be suppressed.

  Further, the sealing part 31 covers the surface of the plating film 33 that covers the surface opposite to the bonding surface of the second substrate 3, so that the stress applied when mounting on the circuit board or the like can be further reduced. . In addition, the sealing part 31 does not necessarily need to be formed in this part. Even in this case, since the sealing portion 31 fills the inside of the through hole, the stress applied to each substrate can be reduced.

In the present modification, a coating film 32 is further formed on each outer electrode so as to cover the sealing portion 31 on the outermost surface opposite to the bonding surface of the second substrate 3. The coating film 32 is formed by nickel plating, gold plating, or the like.
Thereby, when mounting on a circuit board etc. with solder etc., solder wettability can be improved.

(Modification 3)
The arrangement relationship of the through electrode, the electronic device, and the like is not limited to that illustrated in the first embodiment, and can be appropriately changed. For example, the arrangement may be arranged as in Modification 3. Here, FIGS. 11 and 12 are sectional views of another example of the electronic component according to the embodiment of the present invention. Description of the same configuration as in FIG. 3 is omitted.

  As shown in FIG. 11, each bonding film and each extraction electrode are formed on the surface of the first substrate 2. Each through electrode is formed on the second substrate 3. In addition, each mount electrode is formed with a portion of the bonding surface of the second substrate 3 that overlaps with each mount electrode connection portion at a portion adjacent to the recess 9. Each mount electrode is formed from a portion overlapping each mount electrode connecting portion to the bottom surface of the recess 9 through the side surface of the recess 9. The electronic device is mounted on the mount portion of each mount electrode formed on the bottom surface of the recess 9. Thereby, since it is not necessary to process the formation of the through hole or the like, the first substrate 2 can be easily formed.

  The electronic component shown in FIG. 12 is different from that shown in FIG. 3, and each mount electrode has a portion of the joint surface of the second substrate 3 that is adjacent to the recess 9 and overlaps with each mount electrode connection portion. Is done. Each mount electrode is formed from a portion overlapping each mount electrode connecting portion to the bottom surface of the recess 9 through the side surface of the recess 9. The electronic device is mounted on the mount portion of each mount electrode formed on the bottom surface of the recess 9. The first substrate 2 has the same configuration as the electronic component shown in FIG. (Modification 4) In the first embodiment, the case where the joining process by anodic bonding is performed is illustrated, but the present invention is not necessarily limited to this method. For example, the bonding step may be eutectic bonding using gold-based solder such as gold-tin, gold-silicon, or gold-germanium. The bonding process may be metal diffusion bonding using gold tantalum (AuTa) or the like.

Hereinafter, in this modification, the case where the metal diffusion bonding is performed as the bonding step will be described with reference to FIGS.
When metal diffusion bonding is performed, the bonding film 10 and the mount electrode connection portions 19 to 22 are used to bond the first substrate 2 and the second substrate 3 to each other when the first substrate 2 and the second substrate 3 are bonded. It may be formed on either or both of the joining surfaces. In this modification, as shown in FIGS. 13 and 14, the case where the bonding film 10 and the mount electrode connection portions 19 to 22 are formed on both the bonding surfaces of the first substrate 2 and the second substrate 3 is illustrated. .
Here, FIG. 13 is an exploded perspective view of an electronic component according to this modification. 14 is a cross-sectional view of the electronic component shown in FIG. Description of the same configuration as in FIG. 3 is omitted.

  In this modification, thin films such as gold tantalum are used as the bonding film 10 and the extraction electrode 27. The bonding film 10 and the extraction electrode 27 are deposited by stacking tantalum and gold on the bonding portion of the bonding surfaces of the first substrate 2 and the second substrate 3 and the connection portion with the mount electrode and the external electrode. After that, a portion corresponding to the bonding film and the extraction electrode is masked with a photoresist, and an unmasked portion is removed by etching. Next, a method for manufacturing the electronic component 1 according to this modification will be described with reference to FIGS. FIG. 15 is a flowchart showing manufacturing steps of the electronic component shown in FIG. 16 and 17 are cross-sectional views for explaining the manufacturing process of the electronic component shown in FIG. Note that, in the manufacturing process of the electronic component 1 according to the present modification, the same steps as those described in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  Here, the flowchart shown in FIG. 15 is different from the flowchart shown in FIG. 5 in that the bonding film / mount electrode connecting portion forming step (S13) is performed between the mount electrode forming step (S3) and the mounting step (S4). As a joining step (S19), a joining film / mount electrode connecting portion forming step (S14) is provided in place of the connecting film forming step (S7) and the extraction electrode forming step (S8) in FIG. This is a point where metal diffusion bonding is performed.

  That is, in this modification, as shown in FIG. 15 (S13) and FIG. 16 (S13), the bonding film 10 and the mount electrode connecting portion 19 are formed on the bonding surface between the first substrate 2 and the second substrate 3. 20, 21, and 22 can be formed in the same process. Further, as shown in FIG. 15 (S14) and FIG. 16 (S14), in the second substrate 3, the bonding film 10 and the extraction electrodes 27, 28, 29, and 30 can be formed in the same process. In (S13) and (S14), the thin film such as gold tantalum constituting the bonding film 10 and the mount electrode connecting portion and the bonding film 10 and the extraction electrode is formed by the etching process for the above-described stacked gold tantalum. Is done. In (S14), the bonding film 10 and the extraction electrode 27 may be formed in the same process, or a process of sequentially forming each of them may be employed.

  Further, in the bonding step in the present modification, as shown in FIG. 17 (S19), the bonding surfaces of the first substrate 2 and the second substrate 3 are aligned and then pressed in a vacuum or in an atmosphere. -Realized by heating and joining.

  As described above, according to the present modification, the bonding film and the extraction electrode can be made of a material containing gold that can be metal diffusion bonded such as gold tantalum, so that the bonding film and the extraction electrode can have high corrosion resistance. . In addition, according to the present modification, the bonding film for metal diffusion bonding and the extraction electrode can be formed on the bonding surface of the substrate at one time by the etching process, so that the process can be simplified.

  In these embodiments and modifications, the materials of the first substrate and the second substrate and the electronic components can be selected according to the design when mounted on another substrate such as a circuit substrate.

DESCRIPTION OF SYMBOLS 1 Electronic component 2 1st board | substrate 3 2nd board | substrate 4 Electronic device 5, 6, 7, 8 Mount electrode 9 Recess 10 Bonding film 11, 12, 13, 14 Through-hole 15, 16, 17, 18 External electrode 19, 20, 21, 22 Mount electrode connection parts 23, 24, 25, 26 External electrode connection parts 27, 28, 29, 30 Extraction electrode 31 Cathode C Cavity

Claims (6)

An electron having a first substrate, a second substrate bonded to the first substrate and forming a cavity between the first substrate, and an electronic device sealed inside the cavity In parts,
A bonding film for bonding the first substrate and the second substrate outside in the circumferential direction of the cavity;
A through-hole located outside the cavity in the circumferential direction and penetrating from a bonding surface of one of the first substrate and the second substrate to a surface facing the bonding surface;
An external electrode composed of a metal film formed from an inner surface of the through hole to a surface facing the bonding surface of the one substrate;
A mount electrode formed inside the cavity and electrically connected to the electronic device;
A lead electrode electrically connected to the mount electrode,
The lead electrode surrounds the periphery of the opening on the joint surface side of the through hole, joins the first substrate and the second substrate, and is electrically connected to the mount electrode. And an external electrode connection part that covers the opening of the through hole and is connected to the external electrode and the mount electrode connection part.   The electronic component according to claim 1, wherein the external electrode further includes a sealing portion that fills the inside of the through hole. The sealing portion is also laminated on the upper layer of the metal film formed on the surface facing the bonding surface,
The electronic component according to claim 2, further comprising a coating film that covers the sealing portion stacked on the upper layer of the metal film.   4. The electronic component according to claim 1, wherein the mount electrode connection portion is formed of a metal that anodically bonds the first substrate and the second substrate. 5.   The electronic component according to claim 4, wherein the external electrode connection portion is formed of a metal having higher corrosion resistance than the mount electrode connection portion.   The said mount electrode connection part is formed with the metal which can carry out eutectic bonding or diffusion bonding of said 1st board | substrate and said 2nd board | substrate, It is any one of Claims 1-3 characterized by the above-mentioned. Electronic components.

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