JP2015095836A - Method for manufacturing electronic component and electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a thin electronic component capable of stably keeping conduction between an electronic element and an external electrode, and easily forming a through electrode.SOLUTION: A method for manufacturing an electronic component 1 in which an electronic element 30 is embedded, comprises: a through hole formation step for forming a through hole on a glass base 10; an electrode formation step for forming an electrode in a through hole; a mounting step for electrically connecting the electrode and the electronic element; a metal ball arrangement step for arranging a metal ball 50 in the through hole; and an encapsulation step for melting the metal ball.

Description

  The present invention relates to a method for manufacturing an electronic component typified by a crystal resonator or a piezoelectric element, and an electronic component.

  Electronic components such as a gyro sensor, a piezoelectric element, a crystal resonator, and an infrared sensor need to be shielded from the influence of outside air in order to stabilize the characteristics, and thus are desirably placed in a sealed container. As an example of such a package structure, a “glass-ceramic composite and a flat package type piezoelectric component using the same” described later has been proposed (Patent Document 1).

  In the package described in Patent Document 1, a ceramic resonator piece, which is a material having substantially the same thermal expansion coefficient as that of a quartz resonator piece, is mixed in an electronic device in which a quartz resonator piece is placed in a base and a cap is put on the base. A package is constructed using a thing. However, since this package is a glass-ceramic composite, it is made by single-piece production by placing a crystal resonator piece on one base and covering the cap, so the productivity is extremely low. In addition, this package is difficult to process the glass-ceramic composite, which increases production costs.

  In order to eliminate these drawbacks, a method of manufacturing a package with glass that is easy to process has been proposed. As an example, an “electronic component package” described later is known (Patent Document 2).

  The outline of the electronic component package described in Patent Document 2 will be described with reference to FIG. In the electronic component package, a step (a) of forming a through hole in the base 110, a step (b) of pouring low melting glass into the through hole and fitting the metal pin 120, pushing the metal pin 120 and making the glass plate concave Step (c) for processing, step (d) for forming electrode 130 by printing, step (e) for mounting component 140 such as a crystal resonator on metal pin 120, cap 160 and base 110 via sealing material 150 The electronic device 100 is manufactured through the step (f) of sealing and bonding the components. Here, in the step (c), the metal pin 120 adhered and fixed to the base 110 can be obtained by welding the glass at a heating temperature equal to or higher than the softening point temperature (about 1000 ° C.) of the glass. In step f), confidentiality can be reliably maintained, and the electronic device 100 can be manufactured at low cost.

  In such a conventional electronic device manufacturing method, a situation as shown in FIG. 4 may occur in the step (c) of FIG. 3 in which the metal pin is provided on the glass plate. Here, FIG. 4 is an enlarged view of a metal pin portion in the step (c). That is, as shown in FIG. 4C-1, when the metal pin 120 is short or when the push amount is small, the metal pin 120 is wrapped in the low melting point glass 170. For this reason, the situation where the electrical connection of the electrode 130 and metal pin 120 which are formed at a process (d) cannot be ensured may arise. Further, as shown in FIG. 4C-2, even if the metal pin 120 is pushed in as designed, the base 110 is exposed to a temperature equal to or higher than the softening point of the low-melting glass 170. 170 may cover the tip of the metal pin 120. Furthermore, as shown in FIG. 4C-3, the metal pin 120 is exposed to a temperature of about 1000 ° C. As a result, an oxide film 180 grows around the metal pin 120, and the electrode 130 and the electronic component 140 are separated. There may be a situation where conduction is lost. In addition, there is also a demand to provide a low-cost and low-cost requirement for electronic components in recent years (eg, 2012 size, 0.6 mm). Furthermore, although the metal pin is provided, the glass plate is provided with the through hole, so that there is a possibility that the airtightness of the package cannot be sufficiently ensured.

JP-A-11-302034 JP 2003-209198 A

However,
The present invention is made in consideration of such circumstances, and an object of the present invention is to provide an electronic component capable of ensuring the hermeticity of the package while stably ensuring electrical continuity between the external electrode and the internal component of the package. A manufacturing method and an electronic component are provided.

In order to solve the above-described problems, the present invention provides the following means.
The method for manufacturing an electronic component according to the present invention is a method for manufacturing an electronic component incorporating an electronic element, and includes a through-hole forming step for forming a through-hole in a glass base, and an electrode formation for forming an electrode in the through-hole. A mounting step of electrically connecting the electronic element to the electrode; a metal ball disposing step of disposing a metal ball in the through hole; and a sealing step of melting the metal ball. And

  In the electronic component manufacturing method according to the present invention, the diameter of the metal sphere is larger than one opening diameter of the through hole and smaller than the other opening diameter.

  In the electronic component manufacturing method of the present invention, the electrode may be a common electrode in the base on the side where the electronic element is disposed and on the opposite side to the side where the electronic element is disposed. In the internal / external common electrode, in the electrode forming step, the internal / external common electrode is collectively formed through the through hole.

  In the electronic component manufacturing method of the present invention, the inner and outer common electrodes are formed by performing a plating process in the electrode forming step.

  The method of manufacturing an electronic component according to the present invention further includes a joining step of joining a cover that covers the electronic element to the base, and a singulation step of cutting the base and the cover. .

  In the electronic component manufacturing method of the present invention, the metal sphere is an alloy composed of at least two components.

  Moreover, the electronic component of the present invention includes a glass base, and electrodes formed on the inside of the base where the electronic element is disposed and the outside opposite to the side where the electronic element is disposed. An internal / external common electrode integrally formed through a through-hole formed in the base, and a sealing metal embedded in the through-hole and different from the internal / external common electrode.

It is sectional drawing of the electronic component of embodiment which concerns on this invention. It is a figure which shows the manufacturing process of the electronic component of embodiment which concerns on this invention. It is a figure which shows the manufacturing process of a prior art example. It is an expanded sectional view of the metal pin part of a prior art example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view of an electronic component according to the present invention. In the electronic component 1, the electronic element 30 is mounted in a hollow portion that is surrounded by a glass base 10 having a sealing metal 51 and a cover 40 and is blocked from outside air. The electronic element 30 is electrically connected to the internal / external common electrode 12, which is a terminal mounted on the substrate, via the connection unit 20 and the internal / external common electrode 12. Here, the cover 40 is not limited to glass, and for example, when the electronic component 1 is a MEMS device such as a pressure sensor, a cover made of silicon or the like can be used. The cover 40 can be made of aluminum. The inner / outer common electrode 12 has an upper end opening 12a on the side where the electronic element 30 is mounted and a lower end opening 12b on the outside air side, and the area of the upper end opening 12a is smaller than the area of the lower end opening 12b. ing.

  The sealing metal 51 is formed by melting a metal sphere 50 that is larger than the upper end opening 12a and smaller than the lower end opening 12b. When melting, the entire space is placed under vacuum, so that the cavity surrounded by the base 10 and the cover 40 can be evacuated.

  An electronic component 1 shown in FIG. 1 is a crystal resonator on which a tuning-fork type crystal resonator piece is mounted as an electronic element 30. In the present invention, the electronic component 1 includes, but is not limited to, a component on which various electronic components that can be mounted on the base 10 such as a piezoelectric element, an AT cut crystal resonator, a semiconductor circuit, and various sensors are mounted.

  The inner / outer common electrode 12 is made of copper. Moreover, it is not limited to copper, For example, an iron-nickel alloy etc. may be used in consideration of the thermal expansion coefficient with the base. Further, the outermost surface of the inner / outer common electrode 12 may have a layered shape using a noble metal such as gold, silver, or platinum. Here, since the noble metal has a small ionization tendency and has corrosion resistance, it is possible to suppress long-term deterioration of the inner and outer common electrodes 12, so that the reliability of the electronic component 1 using the present invention can be improved. it can. In addition, as a diffusion preventing layer for preventing metal diffusion, a metal layer such as nickel may be formed under the surface layer formed of a noble metal.

  Moreover, the connection part 20 which connects the internal / external common electrode 12 and the electronic element 30 can use conductive adhesives, such as a silver paste, for example. In that case, the inner / outer common electrode 12 and the electronic element 30 are bonded by baking a conductive adhesive (connecting portion 20) such as silver paste as a connecting portion. However, depending on the configuration of the electronic element 30, a conductive adhesive may not be used as the connection portion. For example, when a gold film (gold film) is formed on the outermost surface of the inner / outer common electrode 12, a gold bump (not shown) formed on the electronic element 30 can be used as the connection portion 20. In that case, it is possible to join the gold bumps formed on the electronic element 30 and the gold film of the inner / outer common electrode 12 by thermocompression bonding instead of the conductive adhesive.

  Next, a method for manufacturing the electronic component 1 according to the present embodiment will be described with reference to FIG. FIG. 2 is a diagram showing a method of manufacturing an electronic component that is manufactured at a wafer level so that a large number of electronic components can be manufactured on a common wafer and is finally cut by dicing or the like. The electronic component 1 according to the present embodiment is not limited to this, and may be formed as an individual package from the beginning.

FIG. 2 is a diagram showing a manufacturing process of an electronic component according to the present invention.
FIG. 2A shows a step of forming a through hole in the base 10 (through hole forming step). The through hole is manufactured by sandblasting, laser processing, drilling, hot pressing, or the like. In addition, it is desirable for the through hole to have a different size of one opening of the base and the other opening.

  FIG. 2B is a process of forming the metal film 11 on the base 10 (metal film forming process). The metal film 11 may be a thin film formed by sputtering or electroless plating as a base. Since the metal film 11 is a source of the inner / outer common electrode 12, the wiring resistance is increased in the thin film, and therefore the thickness is increased by electrolytic plating. The plating is often copper, but an iron-nickel alloy may be used in consideration of thermal expansion.

FIG. 2C shows a step of forming the inner / outer common electrode 12 by etching the metal film 11 (electrode formation step). In the electrode forming step, the outermost surface of the inner / outer common electrode 12 may be formed by electroless plating with a noble metal such as gold, silver, or platinum.
FIG. 2D is a diagram for explaining an electronic component connecting process for connecting the inner / outer common electrode 12 and the electronic element 30 so as to be electrically connected via the connecting portion 20 (mounting process). .

  Here, the connection part 20 which connects the internal / external common electrode 12 and the electronic element 30 can use conductive adhesives, such as a silver paste, for example. In that case, the inner / outer common electrode 12 and the electronic element 30 are bonded by baking a conductive adhesive such as a silver paste as a connecting portion. Further, depending on the configuration of the electronic element 30, a conductive adhesive may not be used as the connection portion. For example, when gold is used for the outermost surface of the inner / outer common electrode 12, a gold bump formed on the electronic element 30 can be used as the connection portion 20. In that case, it is possible to join the gold bumps formed on the electronic element 30 and the gold film of the inner / outer common electrode 12 by thermocompression bonding instead of the conductive adhesive.

  FIG. 2E is a diagram for explaining a process of joining the cover 40 processed into a concave shape to the base 10 in order to protect the electronic element 30 mounted on the base 10 (joining process). The material of the cover 40 may be appropriately selected from, for example, silicon, glass, aluminum, and the like in consideration of specifications required for the electronic device 30 such as a bonding method and a degree of vacuum and cost. For example, when the electronic element 30 is a crystal resonator element and the frequency is adjusted after the base 10 and the cover 40 are joined, it is desirable to select a glass member having transparency for the cover 40. The frequency can be adjusted by removing a part of the electronic element 30 by irradiating the laser from the outside of the cover 40. As a method for joining the cover 40 and the base 10, for example, joining using low melting glass, anodic joining, gold-gold joining, or the like can be used.

  FIG. 2F is a process of arranging the metal sphere 50 in the through hole of the base 10. At this time, the metal sphere 50 having a diameter larger than the opening diameter of the upper end opening 12a and smaller than the opening diameter of the lower end opening 12b is used. Further, when the metal ball 50 is used, the metal ball 50 can be installed in the through hole by shaking the wafer and dispersing the metal ball 50. However, the metal sphere 50 is not necessarily a sphere, and may have a shape similar to the shape of the through hole. Further, the melting point of the metal sphere 50 is selected to be higher than the temperature when the electronic component 1 is mounted on the mother board and lower than the melting point of the base 10. As such a material, for example, two-component alloys such as gold tin and high melting point solder can be used.

  FIG. 2G is a process for melting the metal sphere 50. (Sealing step) In this step, a hollow portion that is blocked from outside air is formed by the base 10 and the concave portion of the cover 40. By melting the metal ball 50 in a state where the base 10 and the joined cover 40 are placed under vacuum at the time of melting, the cavity can be kept at a high vacuum. As a means for melting the metal sphere 50, a laser is used. Batch processing is also possible with an oven or the like.

  FIG. 2H is a diagram for explaining a process of dividing the package into pieces (individualization process). That is, the process suggested by FIG. 2H is a process in which a plurality of electronic components are collectively formed on one base 10 and then separated into individual pieces. The joining surface between the base 10 and the cover 40 is cut so as to have a cutting width smaller than the joining width. In this process, depending on the material of the cover 40. Although the method of dividing into pieces by cutting varies, as an example, the electronic component can be divided into pieces by dicing or laser cutting. Thereby, the electronic component which concerns on this invention can be manufactured collectively, and the shortening of the manufacturing time and process in mass production of an electronic component, and cost reduction can be achieved.

As described above, according to the method for manufacturing an electronic component according to the present embodiment, the step of sealing the metal pin by placing the metal ball in the through-hole formed in the base and melting the metal pin is used. Is not used. Therefore, in the present invention, it is possible to avoid a situation in which the metal pin is wrapped in the low melting point glass or an oxide film is formed around the metal pin, so that the electrical continuity between the electronic element and the external electrode is stable. Can be kept.
Therefore, the present invention can be said to be a method of manufacturing an electronic component that can stably maintain conduction between the electronic component and the external electrode and can easily form a through electrode.

  Further, according to the method of manufacturing an electronic component according to the present embodiment, the inner / outer common electrode 12 is formed of a conductive material made of a copper material or an alloy material such as an iron-nickel alloy. That is, when a copper material is used for the inner and outer common electrode 12, a through electrode having a low resistance value can be produced. When an iron-nickel alloy is used as the alloy for the inner / outer common electrode 12, the electrode can be brought close to the thermal expansion coefficient of the base 10, so that a more stable electronic component can be manufactured.

  According to the present invention, the portion that becomes the conventional through electrode uses the inner and outer common electrodes and the step of sealing by melting the metal spheres arranged in the through holes and melting them, and the step of inserting / pushing in the metal pins Is not used. Therefore, in the present invention, it is possible to avoid a situation in which the metal pin is wrapped in the low melting point glass or an oxide film is formed around the metal pin, so that the electrical continuity between the electronic element and the external electrode is stable. Can be kept. Therefore, the present invention has an effect that it is possible to provide a method for manufacturing a small and thin electronic component that can stably maintain conduction between the electronic component and the external electrode and can easily form a through electrode.

  The electronic component of the present invention includes, for example, an oscillator or a watch using the electronic component of the present invention as an oscillator, a portable information device having the electronic component of the present invention in a timekeeping unit, and an electronic component of the present invention as a radio wave such as time information Can be used for an electronic device such as a radio timepiece provided in the receiver.

DESCRIPTION OF SYMBOLS 1 Electronic component 10 Base which formed the through-hole 11 Metal film 12 Inner / outer common electrode 20 Connection part 30 Electronic element 40 Cover 50 Metal ball 51 Sealing metal 100 Electronic device 110 Base 120 Metal pin 130 Electrode 140 Electronic component 150 Sealing material 160 Cap 170 Low melting point glass 180 Oxide film

Claims (7)

A method of manufacturing an electronic component incorporating an electronic element,
A through hole forming step of forming a through hole in a glass base;
Forming an electrode in the through hole; and
A mounting step of electrically connecting the electronic element to the electrode;
A metal sphere arrangement step of arranging a metal sphere in the through hole;
And a sealing step for melting the metal spheres. A method of manufacturing an electronic component according to claim 1,
The diameter of the said metal sphere is larger than one opening diameter of the said through-hole, and is smaller than the other opening diameter, The manufacturing method of the electronic component characterized by the above-mentioned. It is a manufacturing method of the electronic component according to claim 2,
The electrode is an internal / external common electrode that is an electrode common to the inside of the base where the electronic element is disposed and the outside opposite to the side where the electronic element is disposed,
In the electrode forming step, the inner and outer common electrodes are collectively formed through the through holes. In the manufacturing method of the electronic component of Claim 3,
In the electrode forming step, the inner and outer common electrodes are formed by performing a plating process. In the manufacturing method of the electronic component of any one of Claims 1-4,
A bonding step of bonding a cover covering the electronic element to the base;
The method of manufacturing an electronic component, further comprising: an individualizing step of cutting the base and the cover. In the manufacturing method of the electronic component in any one of Claims 1-5,
The method of manufacturing an electronic component, wherein the metal sphere is an alloy composed of at least two components. In electronic parts with built-in electronic elements,
A glass base,
Electrodes formed on the inside of the base on the side where the electronic element is disposed and on the outside opposite to the side on which the electronic element is disposed are integrally formed through a through hole formed in the base. Internal and external common electrodes,
An electronic component comprising: a sealing metal embedded in the through hole and different from the inner and outer common electrodes.

Images