JP2013058689A - Electronic device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device which includes a substrate constituted of a low-cost brittle material, is resistant to stress due to deformation or the like, and has high weather resistance and excellent reliability, and a method for manufacturing the same.SOLUTION: An electronic device 1 comprises: a glass substrate 10; internal wiring 30 provided on an upper surface of the glass substrate 10; an electronic component 50 which is mounted on the glass substrate 10 and is electrically connected to the internal wiring 30; a through electrode 20 having one end connected to the internal wiring 30; an insulating resin layer 70 formed at that position on a lower surface of the glass substrate 10 which is separated from the other end of the through electrode 20; and a conductive resin layer 80 which is laminated so as to cover the periphery of the insulating resin layer 70 and to be connected to the other end of the through electrode 20.

Description

  The present invention relates to an electronic device typified by a crystal resonator and a piezoelectric element, and a manufacturing method thereof.

  Since a crystal resonator is excellent in frequency characteristics, it is frequently used as a device, specifically, one of printed circuit board mounting components. Here, in order to stabilize the characteristics of the crystal resonator, it is necessary to block the influence of outside air. As an example of such a package structure, a “glass-ceramic composite and a flat package type piezoelectric component using the same” described later is known (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. According to FIG. 3, in the electronic component package, the through electrode 200 is formed on the glass substrate 100, and the insulating resin layer 400 having the opening 300 around the through electrode 200 is formed. Furthermore, this electronic component package has a structure in which a conductive resin layer 500 is laminated on an insulating resin layer 400 and an external electrode 600 is laminated on the outer surface of the conductive resin layer 500. As a result, the electronic component package is formed of a substrate using a low-cost glass material, and thus an electronic component that is resistant to stress such as deformation can be realized even when mounted on an electronic circuit board. Therefore, the electronic component package is flexible and can have excellent stress relaxation characteristics, and by relaxing the stress, cracks etc. occur in the glass substrate even when soldered to the electronic circuit board. Therefore, reliability is improved.

JP-A-11-302034 JP 2010-103479 A

  However, in the above electronic component package, since the insulating resin layer 400 is exposed to the surrounding environment (a part is exposed to the outside), the insulating resin layer 400 expands and contracts as a result of moisture absorption and drying. There is a problem of deterioration.

  An object of the present invention is to provide a highly reliable electronic device having a substrate made of a brittle material at low cost, resistant to stress such as deformation, and having high weather resistance, and a method for manufacturing the electronic device. .

In order to solve the above-described problems, the present invention provides the following means.
The invention according to claim 1 is an electronic device, wherein the substrate is formed of a brittle material, an internal electrode provided on one of upper and lower surfaces of the substrate, and mounted on the substrate. An electronic component electrically connected to an electrode; a through electrode vertically penetrating the substrate; one end connected to the internal electrode; and a surface of the substrate facing the surface on which the internal electrode is provided. An insulating resin layer formed at a position apart from the other end of the insulating resin layer, and a conductive resin layer that covers the periphery of the insulating resin layer and is laminated so as to be connected to the other end of the through electrode. And

  A second aspect of the invention is the electronic device according to the first aspect, wherein the conductive resin layer is covered with a conductive plating layer.

  A third aspect of the present invention is the electronic device according to the second aspect, wherein the plating layer is a gold plating layer.

  Invention of Claim 4 is an electronic device as described in any one of Claims 1-3, Comprising: In order to accommodate the said electronic component inside in the joint surface with the said board | substrate, and the said board | substrate The cover part which has a recessed part of this is provided, It is characterized by the above-mentioned.

  The invention according to claim 5 is a method of manufacturing an electronic device, wherein a step of forming a through electrode penetrating the substrate up and down on a substrate formed of a brittle material and one end of the through electrode are connected. As described above, the step of disposing an internal electrode on one of the upper and lower surfaces of the substrate, the step of mounting an electronic component on the substrate so as to be electrically connected to the internal electrode, and the surface of the substrate on which the internal electrode is disposed A step of forming an insulating resin layer at a position spaced from the other end of the through electrode on the surface facing the through electrode, and a conductive resin layer so as to cover the periphery of the insulating resin layer and to be connected to the other end of the through electrode. And a step of laminating.

  The invention according to claim 6 is the method for manufacturing the electronic device according to claim 5, comprising a step of covering the conductive resin layer with a conductive plating layer.

  The invention described in claim 7 is the method of manufacturing the electronic device according to claim 6, wherein the plating layer is a gold plating layer.

  Invention of Claim 8 is a manufacturing method of the electronic device as described in any one of Claim 5-7, Comprising: After forming the several electronic device on one said board | substrate collectively, the said electronic device Characterized in that it comprises a step of singulation.

  Invention of Claim 9 is a manufacturing method of the electronic device as described in any one of Claims 5-8, Comprising: After mounting an electronic component in the said board | substrate, the said electron is bonded to the said board | substrate. It is characterized by comprising a step of joining a cover portion having a recess for accommodating a component inside to the substrate.

  Here, silicon and glass are employed as the brittle material. These have the advantage of being low in cost compared to ceramics, particularly alumina, plastics and metals frequently used as packages. The insulating resin layer and the conductive resin layer are formed by a screen printing method. In addition, a large number of electronic components and a large number of external electrodes can be collectively formed on the substrate, and the formed electronic device can be divided into individual pieces.

  According to the present invention, in the electronic device, the insulating resin layer is formed on the other end side of the through electrode. That is, the electronic device according to the present invention can suppress the destruction of the substrate against the stress acting on the substrate due to the property of the insulating resin that is flexible and has stress relaxation properties. Furthermore, in the electronic device according to the present invention, the periphery of the insulating resin layer is covered with a conductive resin layer so that the insulating resin layer is not exposed to the outside. Therefore, moisture absorption and drying can be prevented from occurring in the insulating resin layer, and deterioration due to expansion and contraction can be prevented.

  Therefore, the present invention can provide a highly reliable electronic device in which the substrate is made of a brittle material at low cost, is strong against stress such as deformation, has high weather resistance, and a method for manufacturing the electronic device. .

It is sectional drawing of the electronic device which concerns on this invention. It is a figure which shows the manufacturing process of the electronic device which concerns on this invention. It is sectional drawing of the electronic device 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 device according to the present invention. In the electronic device 1, the electronic component 50 is mounted in a hollow portion 90 that is surrounded by the glass substrate 10 (substrate) and the cover 60 (cover portion) and is blocked from outside air. The electronic component 50 is electrically connected to the conductive resin layer 80 formed so as to cover the insulating resin layer 70 via the mounting portion 40, the internal wiring 30 (internal electrode), and the through electrode 20.

  The electronic device 1 is a crystal resonator on which a tuning-fork type crystal resonator piece is mounted as the electronic component 50. The electronic device 1 is not limited to a crystal resonator, and includes an electronic device that can mount various electronic components 50 on the glass substrate 10, such as an AT-cut crystal resonator, a semiconductor circuit, an LED, and various sensors. The electronic device 1 may not have the cover 60 when an LED or the like is mounted as the electronic component 50.

  The glass substrate 10 is a plate-like member formed of a brittle material such as a glass material. The brittle material is not limited to a glass material, and may be, for example, concrete, ceramics, cast iron, or the like.

  The cover 60 is a glass material in which a concave portion is formed on the surface facing the glass substrate 10. The concave portion of the cover 60 and the upper surface of the glass substrate 10 form a hollow portion 90 in a state where the cover 60 is bonded to the glass substrate 10. Here, the cover 60 is not limited to glass. For example, when the electronic device 1 is a MEMS device such as a pressure sensor, a cover made of silicon or the like can be used. The cover 60 can be made of aluminum.

  The internal wiring 30 is a wiring member disposed in a cavity 90 formed of a metal film, and a surface layer is formed using a noble metal such as gold, silver, or platinum. Here, since the noble metal has a small ionization tendency and has corrosion resistance, long-term deterioration can be suppressed, and thus the reliability of the electronic device 1 can be improved. Moreover, the internal wiring 30 may form a metal layer of nickel or the like as a base layer of a surface layer formed of a noble metal as a diffusion preventing layer for preventing metal diffusion. A sputtering method is a general method for forming the internal wiring 30. Further, a plating method can be used as a method for forming the internal wiring 30.

  The mounting portion 40 is a member that supports the electronic component 50 by electrically connecting the internal wiring 30 and the electronic component 50. For the mounting part 40, for example, a conductive adhesive such as silver paste can be used. Here, the internal wiring 30 and the electronic component 50 are bonded by baking a conductive adhesive such as a silver paste which is the mounting portion 40. However, depending on the configuration of the electronic component 50, the conductive adhesive may not be used as the mounting portion 40. For example, when gold is used for the outermost surface of the internal wiring 30, gold bumps (not shown) formed on the electronic component 50 can be used as the mounting portion 40. In this case, gold-gold bonding or the like in which gold bumps (mounting portion 40) formed on the electronic component 50 and the gold film of the internal wiring 30 are bonded by thermocompression bonding can be used instead of bonding with the conductive adhesive. .

  The through electrode 20 is an electrode formed in a through hole penetrating the glass substrate 10 in the vertical direction. The through electrode 20 is made of a metal lead such as Ag, an Ag—Pd metal alloy, a thick film electrode filled with a thick film paste formed of glass frit, and fired, an Fe—Ni alloy, a Kovar alloy, or a jumet wire. Is composed of a hermetically sealed electrode sealed with glass frit or a metal sealed with solder or plating.

  The insulating resin layer 70 is a layer of insulating resin formed on the surface of the glass substrate 10 (surface facing the surface on which the internal wiring 30 of the glass substrate 10 is provided) at a position separated from the end of the through electrode 20. is there. The conductive resin layer 80 is a layer of conductive resin laminated so as to cover the periphery of the insulating resin layer 70 and to be connected to the end portion of the through electrode 20. A plating layer (metal film) such as gold plating laminated on the surface of the conductive resin layer 80 functions as an external electrode 95 as a terminal mounted on the glass substrate 10. Note that both the insulating resin of the insulating resin layer 70 and the conductive resin of the conductive resin layer 80 contain an epoxy resin.

  Here, since the insulating resin is flexible and has stress relaxation characteristics, there is an advantage of suppressing the breakage of the glass substrate 10 against various stresses. However, the insulating resin has a drawback that external electrodes cannot be formed by plating. On the other hand, the conductive resin has an advantage that an external electrode can be formed by plating. However, the conductive resin has the disadvantage that it is harder than the insulating resin and has poor stress relaxation characteristics. In addition, since the conductive resin has a lower resin content than the insulating resin, the adhesiveness with the glass is also inferior.

  Therefore, as described above, by forming the insulating resin layer 70 on the glass substrate 10, the insulating resin layer 70 exhibits a high stress relaxation effect of the insulating resin and adhesion to the glass substrate 10. Furthermore, since the external electrode 95 is formed on the conductive resin layer 80 covering the insulating resin layer 70, the external electrode 95 can be easily formed by plating with a conductive resin. Moreover, since the insulating resin layer 70 and the conductive resin layer 80 contain an epoxy resin as described above, they can be firmly adhered to each other.

  As described above, it is possible to obtain an electrode forming structure that can utilize the adhesiveness between the insulating resin and the conductive resin and is excellent in the stress relaxation effect and the adhesiveness. Although there is a concern that both the insulating resin and the conductive resin may expand and contract due to moisture absorption or drying, moisture absorption or drying can be achieved by using a metal film formed by plating such as gold plating as the external electrode 95 as in this structure. Expansion and contraction due to can be prevented.

  Here, the thicknesses of the insulating resin layer 70 and the conductive resin layer 80 are each preferably about 10 to 30 μm when each resin layer is formed by screen printing. For example, when the layer thickness is 10 μm or less, it is difficult to relieve the stress of the glass substrate 10. Moreover, since it is not easy to form the thickness of each resin layer to 30 μm or more, the production cost increases. As described above, by making the thickness of each of the insulating resin layer 70 and the conductive resin layer 80 about 10 μm to 30 μm, the respective resin layers can be manufactured at low cost and have a high stress relaxation effect. Is obtained.

  As described above, the structure having the two-layer structure of the insulating resin layer and the conductive resin layer shown in the present embodiment has excellent stress relaxation characteristics as compared with the structure of the insulating resin single layer or the conductive resin single layer. And the adhesiveness with a glass substrate is very high. Furthermore, since the synthetic resin and the insulating resin constituting the conductive resin can take various combinations, the electronic device 1 having the electrode having the two-layer structure of the present invention has high reliability in a high temperature and high humidity environment and a temperature cycle. .

  In particular, in general, there are restrictions on resins that can be used as the conductive resin in consideration of adhesion to glass, temperature cycle, and the like. However, by adopting the two-layer structure of the insulating resin and the conductive resin according to this embodiment, various conductive resins can be used.

(Electronic device manufacturing method)
Next, a method for manufacturing the electronic device 1 will be described with reference to FIG. FIG. 2 shows a method of manufacturing an electronic device that is manufactured at the wafer level and finally cut by dicing or the like. In addition, this invention is not limited to this, You may form with an individual package from the beginning.

FIG. 2 is a diagram showing a manufacturing process of the electronic device according to the present invention.
FIG. 2A is a diagram for explaining a process of forming a through hole in the glass substrate 10. Here, the through hole is manufactured by sand blasting, laser processing, drilling, hot pressing, or the like.

  FIG. 2B is a diagram for explaining a process of forming the through electrode 20 in the through hole formed in the previous process. The through electrode 20 is made of Ag, Ag—Pd-based metal alloy, a thick film electrode filled with a thick film paste formed of glass frit, and fired, or a metal lead such as Fe—Ni alloy, Kovar alloy, or dumet wire. A hermetically sealed electrode sealed with glass frit or a metal sealed with solder or plating can be used.

  FIG. 2C is a diagram for explaining a process of forming the internal wiring 30 on one of the upper and lower surfaces of the base substrate 10 (the upper surface of FIG. 2C) so as to be electrically connected to the through electrode 20. It is. Here, the internal wiring 30 is formed using a sputtering method, a plating method, or the like.

  FIG. 2D is a diagram for explaining an electronic component connecting step for connecting the internal wiring 30 and the electronic component 50 via the mounting portion 40. Here, the mounting part 40 which connects the internal wiring 30 and the electronic component 50 can use conductive adhesives, such as a silver paste, for example. In that case, the internal wiring 30 and the electronic component 50 are bonded by baking a conductive adhesive such as silver paste as a connecting portion. In addition, depending on the configuration of the electronic component 50, the conductive adhesive may not be used as the connection portion. For example, when gold is used for the outermost surface of the internal wiring 30, gold bumps formed on the electronic component 50 can be used as the mounting portion 40. In that case, the gold bump formed on the electronic component 40 and the gold film of the internal wiring 30 can be bonded by using thermo-compression bonding instead of the conductive adhesive.

  FIG. 2E is a diagram for explaining a cap joining process for joining the cover 60 provided with a recess to the glass substrate 10 in order to protect the electronic component 50 mounted on the glass substrate 10. In this step, the cavity 90 is formed by the surface (upper surface) facing the recess of the cover of the glass substrate 10 and the recess of the cover 60. Thereby, an electronic component is provided in the cavity 90. Moreover, the material of the cover 60 can use silicon, glass, aluminum etc., for example, and should just select it in consideration of the specifications requested | required of the electronic components 50, such as a joining method and a vacuum degree, cost. For example, when the electronic component 50 is a crystal resonator piece and the frequency is adjusted after the glass substrate 10 and the cover 60 are joined, it is desirable to select a glass member for the cover 60. As a bonding method, for example, adhesion, anodic bonding, gold-gold bonding, or the like can be used. In addition, when the recessed part is formed in the glass substrate 10 side, it is not necessary to form a recessed part in the cover 60. FIG. In this case, since the cavity is formed by the recess of the glass substrate 10 and the surface of the cover 60 facing the recess, the electronic component 50 may be provided in the cavity.

  FIG. 2F is a diagram for explaining a process of forming the insulating resin layer 70 on the surface of the glass substrate 10 (a surface facing the surface on which the internal wiring 30 is formed). The insulating resin layer 70 is formed by screen printing. At this time, since the insulating resin layer 70 is not electrically connected when the end portion of the through electrode 20 is covered, the insulating resin layer 70 is formed so as to open (with a gap from the end portion) on the end portion of the through electrode 20.

  FIG. 2G is a diagram for explaining a process of forming a conductive resin layer 80 so as to cover the insulating resin layer 70 and plating the conductive resin layer 80. Here, the conductive resin layer 80 is formed by screen printing. And after the conductive resin layer 80 is heated and solidified, the external electrode 95 used as the mounting part with the glass substrate 10 is formed by electroless plating. The outermost surface of the metal film formed by electroless plating uses a noble metal such as gold, silver or platinum.

  FIG. 2H is a diagram for explaining the process of dividing the package into individual pieces. In other words, this is a step of forming a plurality of electronic devices 1 on a single glass substrate 10 and then separating the electronic devices 1 into individual pieces. In this step, although the method of dividing into pieces varies depending on the material of the cover 60, for example, dicing or laser cutting can be used.

  The electronic device of the present invention includes, for example, an oscillator or a clock using the electronic device of the present invention as an oscillator, a portable information device including the electronic device of the present invention in a timekeeping section, and 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 device 10 Glass substrate 20 Through electrode 30 Internal wiring 40 Mounting part 50 Electronic component 60 Cover 70 Insulating resin layer 80 Conductive resin layer 90 Cavity part 95 External electrode 100 Glass substrate 200 Through electrode 300 Opening part 400 Insulating resin layer 500 Conductive resin Layer 600 External electrode

Claims (9)

A substrate formed of a brittle material;
An internal electrode provided on one of the upper and lower surfaces of the substrate;
An electronic component mounted on the substrate and electrically connected to the internal electrode;
A through electrode that vertically penetrates the substrate and has one end connected to the internal electrode;
An insulating resin layer formed at a position spaced from the other end of the through electrode on the surface of the substrate facing the surface on which the internal electrode is provided;
A conductive resin layer that covers the periphery of the insulating resin layer and is laminated so as to be connected to the other end of the through electrode;
An electronic device comprising:   The electronic device according to claim 1, wherein the conductive resin layer is covered with a conductive plating layer.   The electronic device according to claim 2, wherein the plating layer is a gold plating layer.   The electronic device according to any one of claims 1 to 3, further comprising a cover portion that is bonded to the substrate and has a concave portion for accommodating the electronic component therein on a bonding surface with the substrate. . A step of forming a through electrode penetrating the substrate up and down on a substrate formed of a brittle material;
Disposing an internal electrode on one of the upper and lower surfaces of the substrate so as to be connected to one end of the through electrode;
Mounting an electronic component on the substrate so as to be electrically connected to the internal electrode;
Forming an insulating resin layer at a position spaced from the other end of the through electrode on the surface of the substrate facing the surface on which the internal electrode is disposed;
Laminating a conductive resin layer so as to cover the periphery of the insulating resin layer and to be connected to the other end of the through electrode;
An electronic device manufacturing method comprising:   The method for manufacturing an electronic device according to claim 5, further comprising a step of covering the conductive resin layer with a conductive plating layer.   The method of manufacturing an electronic device according to claim 6, wherein the plating layer is a gold plating layer.   The method for manufacturing an electronic device according to claim 5, further comprising a step of separating the electronic devices after forming a plurality of electronic devices on one substrate at a time. .   6. After mounting an electronic component on the substrate, the method includes a step of bonding to the substrate a cover portion having a recess for accommodating the electronic component inside the bonding surface with the substrate. The manufacturing method of the electronic device as described in any one of 8.

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