WO2006025139A1 - Circuit board, manufacturing method thereof, and electronic parts using the same - Google Patents

Abstract

A circuit board capable of being thinned and reduced in its manufacturing cost, a method for manufacturing the circuit board, and electronic parts using the circuit board and capable of improving gastightness. The circuit board (1) comprises an insulating substrate (10), a through hole (11) formed in the thickness direction of the insulating substrate (10) for connecting the first principal plane (10a) of the insulating substrate (10) and the second principal plane (10b) of the insulating substrate (10), a conductive film (12) formed on the inner wall of the through hole (11) and around the opening of the through hole (11) on the first and second principal planes (10a and 10b); and a metallic member (14) fitted in the through hole (11) and jointed to the conductive film (12).

Description

 Specification

 Circuit board, manufacturing method thereof, and electronic component using the same

 Technical field

 TECHNICAL FIELD [0001] The present invention relates to a circuit board on which a quartz crystal semiconductor element or the like is mounted, a manufacturing method thereof, and an electronic component using the circuit board.

 Background art

 Conventionally, in a circuit board on which an electronic element such as a crystal piece or a semiconductor element is mounted, an electrically conductive portion is formed by filling a through hole formed in a ceramic substrate with a conductive composition. Further, as a formation method thereof, a method of forming an electrically conductive portion through a drying step and a heat treatment step after filling the through hole with a conductive composition was used. Further, as an electronic component, there is one in which a circuit board on which an electronic element is mounted is covered and protected with a lid (for example, see Patent Document 1).

 FIG. 7 is a cross-sectional view of an electronic component using the conventional circuit board described in Patent Document 1. As shown in FIG. 7, in the electronic component 104, the conductive composition 108 is filled with a conductive composition in a through hole 110 formed at a predetermined position of the insulating substrate 102 having a ceramic material force, and heat treatment is performed. Is formed. Further, as the conductive composition, a mixture containing silver particles, glass powder, and a vehicle is used. In this mixture, the silver particle content is in the range of 85 to 90% by weight with respect to the total amount of silver particles and glass powder, and the soft temperature of the contained glass powder is about 550 to 650 ° C. In addition, as the insulating substrate 102, a substrate including an inorganic powder and a binder that is fired and then finished into a flat plate shape and further provided with a recess 105 is used.

 Further, the electronic component 104 includes a wiring layer 106 and a wiring layer 107, an electronic element (crystal piece) 101 mounted on the wiring layer 107, and a lid provided on the insulating substrate 102 so as to cover the electronic element 101. Including body 103. The lid 103 and the wiring layer 107, and the electronic element 101 and the wiring layer 107 are bonded together via a bonding layer 109 having a force of gold-tin alloy or gold-silicon alloy. Patent Document 1: Japanese Patent Laid-Open No. 2003-101181

However, in the conventional configuration, when the electrically conductive portion is formed, a heat of 750 ° C. to 900 ° C. Since processing is required, it is difficult to use an insulating substrate other than a ceramic substrate. As a result, the ratio of material costs to manufacturing costs increased and manufacturing costs could increase.

 [0006] Further, a generally used ceramic substrate must contain an aggregate of alumina particles having a minimum diameter of about 0.7 μm. Since there is a grain boundary between the alumina particles, the thickness is 150 μm. If an electronic component is configured using a ceramic substrate of m or less, it may be difficult to maintain the airtightness of the electronic component. Further, when the thickness of the ceramic substrate is reduced, there is a possibility that the ceramic substrate is warped by heat treatment when forming the electrically conductive portion. For this reason, there is a possibility that it is more difficult to maintain the airtightness of the electronic component.

 Disclosure of the invention

 [0007] The present invention solves the above-described problem, and can be reduced in thickness and can be reduced in manufacturing cost, a manufacturing method thereof, and an electronic part capable of improving hermeticity using the circuit board Provide goods.

 [0008] A first circuit board of the present invention connects an insulating substrate and a first main surface of the insulating substrate and a second main surface of the insulating substrate formed in the thickness direction of the insulating substrate. A circuit board including a through hole for

 A conductive film formed on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;

 A metal member that fills the through-hole and is bonded to the conductive film.

 [0009] A second circuit board of the present invention connects an insulating substrate and a first main surface of the insulating substrate and a second main surface of the insulating substrate formed in the thickness direction of the insulating substrate. A circuit board including a through hole for

 A conductive film formed on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;

 And a metal member that closes the opening of the through hole on the first main surface side and is in contact with the conductive film.

[0010] The first manufacturing method of the circuit board of the present invention, In the thickness direction of the insulating substrate, a through hole for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate is formed,

 Forming a conductive film on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;

 In this method, the through-hole is filled with a substantially spherical metal member, and the metal member and the conductive film are joined.

[0011] The second manufacturing method of the circuit board of the present invention,

 In the thickness direction of the insulating substrate, a through hole for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate is formed,

 Forming a conductive film on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;

 In the method of manufacturing a circuit board, the opening on the first main surface side in the through hole is closed with a substantially spherical metal member, and the metal member and the conductive film are joined.

[0012] A first electronic component of the present invention connects an insulating substrate and a first main surface of the insulating substrate and a second main surface of the insulating substrate formed in the thickness direction of the insulating substrate. A circuit board including a through hole for

 Electronic elements mounted on the circuit board;

 An electronic component including a lid that covers the electronic element,

 The circuit board includes a conductive film formed on an inner wall of the through hole and around the opening of the through hole in the first and second main surfaces, and is filled in the through hole and bonded to the conductive film. A metal member,

 The electronic element is mounted on the conductive film formed around the opening in the first main surface via a conductive material.

[0013] A second electronic component of the present invention connects an insulating substrate and a first main surface of the insulating substrate and a second main surface of the insulating substrate formed in the thickness direction of the insulating substrate. A circuit board including a through hole for

 Electronic elements mounted on the circuit board;

An electronic component including a lid that covers the electronic element, The circuit board includes a conductive film formed on an inner wall of the through hole and around the opening of the through hole in the first and second main surfaces, and an opening on the first main surface side in the through hole. The electronic element is mounted on the metal member, and includes a metal member bonded to the conductive film.

[0014] According to the circuit board of the present invention and the method for manufacturing the circuit board, since the heat treatment at a high temperature is not required when forming the electrically conductive portion, for example, a substrate (such as a glass substrate) other than the ceramic substrate is used. Can do. Therefore, the thickness can be reduced and the manufacturing cost can be reduced. Further, according to the electronic component of the present invention, since the circuit board of the present invention is used, the airtightness can be improved.

 Brief Description of Drawings

 FIG. 1A is a cross-sectional view of a circuit board according to a first embodiment of the present invention, and FIG. 1B is a schematic plan view of the circuit board according to the first embodiment of the present invention.

 FIG. 2 is a cross-sectional view of an electronic component according to a second embodiment of the present invention.

 3A to 3J are process cross-sectional views illustrating an example of a method for manufacturing an electronic component according to a second embodiment of the present invention.

 FIG. 4 is a cross-sectional view of a circuit board according to a third embodiment of the present invention.

 FIG. 5 is a cross-sectional view of an electronic component according to a fourth embodiment of the present invention.

 6A to 6D are process cross-sectional views illustrating an example of a method for manufacturing an electronic component according to a fourth embodiment of the present invention.

 FIG. 7 is a cross-sectional view of an electronic component using a conventional circuit board.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0016] A first circuit board of the present invention is for connecting an insulating substrate and a first main surface of the insulating substrate and a second main surface of the insulating substrate formed in the thickness direction of the insulating substrate. Including through-holes. Here, the “first main surface” means the main surface of the insulating substrate on the side where the electronic element is mounted when the circuit board is applied to an electronic component described later. The same applies to the second circuit board of the present invention described later.

[0017] The insulating substrate is preferably a glass substrate. The glass substrate has a seamless structure made by connecting silicon oxide molecules, so it is denser than the ceramic substrate. Has been. Therefore, when the insulating substrate is a glass substrate, the airtightness of the electronic component can be improved when applied to the electronic component described later. As the glass substrate, for example, borosilicate glass thermal expansion coefficient of ^{3 X 10- 6 Z ° C~8 X} 10- 6 Z ° C, also the thermal expansion coefficient of 3 X 10- ⁶ Z ° C~8 X 10- ⁶ Z ° alkali-free glass and C, or a thermal expansion coefficient of 8 X 10- ⁶ Z ° C~ 1. soda glass of 2 X 10- ⁵ Z ° C can be used. The thickness is, for example, about 100 to 300 μm.

 [0018] It is preferable that the diameter of the through hole gradually decreases from the first main surface to the second main surface. This is because the metal member described later can be easily filled. The diameter of the through hole may be set appropriately according to the thickness of the insulating substrate.For example, when the thickness of the insulating substrate is 150 m, the opening diameter on the first main surface side is 100 m or more and 150 μm or less. The opening diameter on the second main surface side should be in the range of 50 μm to 100 μm. The through hole can be formed by, for example, a sand blast method or an etching method. In particular, when a through hole is formed by the sand blast method, the inner wall of the through hole is appropriately roughened by the blasting medium, so that the adhesion between the inner wall of the through hole and the conductive film described later is improved.

 [0019] The first circuit board of the present invention includes a conductive film formed on the inner wall of the through hole, the periphery of the opening of the through hole on the first and second main surfaces, and the through hole. A metal member that is filled and bonded to the conductive film. The metal member also has a metal material force such as gold and copper, for example, and therefore does not require a heat treatment at a high temperature (for example, 750 ° C. or higher) when joining the conductive film. Therefore, since a substrate other than a ceramic substrate (eg, a glass substrate) can be used, a circuit substrate that can be reduced in thickness and can be manufactured at a reduced cost can be provided.

[0020] As the conductive film, for example, a metal thin film made of chromium, titanium, nickel, noradium, gold or the like can be used. The conductive film may be formed of one layer of metal thin film or a plurality of layers of metal thin film. In the case of forming with a plurality of metal thin films, a conductive film in which a palladium thin film and a gold thin film are sequentially laminated on a chromium thin film is preferable. This is because the palladium thin film functions as an adhesion layer between the gold thin film and the chromium thin film because the palladium thin film is interposed between the chromium thin film and the gold thin film serving as the protective layer. In addition, the chrome thin film Since a glass substrate is used as the insulating substrate, a conductive film of the above combination (chrome thin film z palladium thin film Z gold thin film) is particularly preferable because of its high adhesion. The thickness of each metal thin film in the above combination is, for example, about 0.05-0. For a chromium thin film, about 0.01-0.05 m for a radium thin film, 0.3 to 1. Ο μm. The above-mentioned metal thin film can be formed using means such as a sputtering method or a plating method. For example, when a chromium thin film, a titanium thin film, or a palladium thin film is formed to a thickness of about 0.05 to 0.1 μm, it can be formed by a sputtering method. For example, when a nickel thin film is formed to a thickness of about 1 to 2 m, it can be formed using an electroless plating method. In addition, when a gold thin film is formed to a thickness of about 0.3 to 1.0 m as a protective layer for a metal thin film formed by a sputtering method or a plating method, the electrolytic plating method should be used. Can do. The gold thin film can also be formed by a sputtering method. A silver thin film or a copper thin film may be used instead of the gold thin film. A silver thin film or a copper thin film can be formed by a sputtering method or a plating method in the same manner as a gold thin film.

 [0021] The metal member is preferably formed in a substantially spherical shape. This is a force that enables uniform bonding between the conductive film formed on the inner wall of the through hole and the metal member.

 [0022] Preferably, the insulating substrate is formed in a sheet shape! When applied to electronic components, which will be described later, it is also a force that facilitates thinning of electronic components. Further, when the insulating substrate is formed in a sheet shape, when an electronic component to be described later is manufactured, a plurality of electronic elements are simultaneously mounted on the insulating substrate, and then the electronic components are separated into individual electronic components. As a result, it is possible to simplify the mounting process of the electronic element.

 Next, the second circuit board of the present invention will be described. In the following description, description of the same components as those of the first circuit board of the present invention described above may be omitted.

[0024] The second circuit board of the present invention is the same as the first circuit board of the present invention described above, and the first main substrate of the insulating substrate formed in the thickness direction of the insulating substrate. A through hole for connecting the surface and the second main surface of the insulating substrate, and the inner wall of the through hole and the first and second main surfaces And a conductive film formed around the opening of the through hole on the surface. In addition to the above configuration, the second circuit board of the present invention includes a metal member that closes the opening on the first main surface side of the through hole and is bonded to the conductive film. As a result, similar to the above-described first circuit board of the present invention, it is possible to provide a circuit board that can be reduced in thickness and reduced in manufacturing cost.

 [0025] Further, the second circuit board of the present invention may be a circuit board in which the metal member is formed in a substantially hemispherical shape and the hemispherical surface of the metal member and the conductive film are joined. . The conductive film formed around the opening on the first main surface side and the metal member can be uniformly joined, and the flat surface portion located on the opposite side of the hemispherical surface of the metal member. In addition, it is a force that can mount an electronic element to be described later.

 [0026] In addition, the insulating substrate used for the second circuit board of the present invention is formed in a sheet shape, which is preferably a glass substrate, like the first circuit board of the present invention described above. It is preferable.

 Next, a first method for manufacturing a circuit board according to the present invention will be described. The first manufacturing method of the circuit board of the present invention is a preferable manufacturing method for manufacturing the above-described first circuit board of the present invention. Therefore, in the following description, description overlapping with the above-described first circuit board of the present invention may be omitted.

 [0028] In the first manufacturing method of the circuit board of the present invention, first, through holes for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate are formed in the thickness direction of the insulating substrate. Then, a conductive film is formed on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces. The through hole and conductive film are formed as described above. In addition, the insulating substrate to be used is preferably formed in a sheet shape that is preferably a glass substrate in the same manner as the first circuit board of the present invention described above.

 [0029] Then, the through-hole is filled with a substantially spherical metal member, and the metal member and the conductive film are joined. As a result, the above-described first circuit board of the present invention can be easily manufactured. The “substantially spherical metal member” can be formed by using, for example, a single tool, and details of the forming method will be described later.

[0030] Further, when the metal member and the conductive film are joined, the ultrasonic combined thermocompression method is used. It is preferable to join. In this case, the “ultrasonic combined thermocompression bonding method” is a method in which ultrasonic waves are applied and bonded to a bonding portion between the metal member and the conductive film while applying heat and a load. The thermocompression bonding method using ultrasonic waves is a conventional method in which heat and load are applied (thermocompression bonding method).

) Can be joined at a lower temperature (about 100 to 300 ° C) than the heating temperature (temperature exceeding 300 ° C). Therefore, deformation of the insulating substrate can be prevented. Further, by using ultrasonic waves in combination, the conductive film and the metal member are more strongly bonded to each other by the frictional heat generated by the ultrasonic waves as compared with the above-mentioned “thermocompression bonding method”.

 [0031] Next, a second method for manufacturing a circuit board according to the present invention will be described. The second manufacturing method of the circuit board of the present invention is a preferable manufacturing method for manufacturing the above-described second circuit board of the present invention. Moreover, in the following description, the description which overlaps with the 1st manufacturing method of the 2nd circuit board of this invention mentioned above and the circuit board of this invention mentioned above may be abbreviate | omitted.

 [0032] In the second manufacturing method of the circuit board of the present invention, first, through holes for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate are formed in the thickness direction of the insulating substrate. Then, a conductive film is formed on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces. Then, the opening on the first main surface side of the through hole is closed with a substantially spherical metal member, and the metal member and the conductive film are joined. Thereby, the above-described second circuit board of the present invention can be easily manufactured.

 [0033] In addition, the insulating substrate used in the second manufacturing method of the circuit board of the present invention is preferably a glass substrate as in the above-described first manufacturing method of the circuit board of the present invention. It is preferable that it is formed in a shape. Moreover, when joining the said metal member and the said electrically conductive film, it is preferable to join by the ultrasonic thermocompression bonding method as mentioned above.

 Next, the first electronic component of the present invention will be described. The first electronic component of the present invention is an electronic component including the above-described first circuit board of the present invention. Therefore, in the following description, description of the same components as those of the above-described first circuit board of the present invention may be omitted.

[0035] A first electronic component of the present invention includes the above-described first circuit board of the present invention, an electronic element mounted on the first circuit board, and a lid that covers the electronic element. And the electron The element is mounted on a region formed around the opening of the first hole in the first main surface of the conductive film of the first circuit board of the present invention described above via a conductive material. As described above, since the first circuit board of the present invention does not require heat treatment at a high temperature, a substrate other than a ceramic substrate (for example, a glass substrate) can be used. Therefore, according to the first electronic component of the present invention, the airtightness of the electronic component can be improved.

[0036] As the electronic element, for example, a crystal piece or a semiconductor element can be used. For example, when the electronic element is a crystal piece, the electronic component is a crystal resonator. The material for the lid is not particularly limited, and for example, glass or the like can be used. The thickness of the lid is, for example, about 0.3 to 0.4 mm. Further, as the conductive material, for example, a conductive adhesive in which silver fine particles are mixed as conductive fine particles with epoxy resin can be used.

 [0037] In addition, a recess may be formed in a region of the first main surface facing the electronic element. This is because it is easy to secure the operation space of the electronic element.

 Next, the second electronic component of the present invention will be described. The second electronic component of the present invention is an electronic component including the above-described second circuit board of the present invention. In the following description, description of the same components as those of the second circuit board of the present invention described above and the first electronic component of the present invention described above may be omitted.

 [0039] A second electronic component of the present invention includes the above-described second circuit board of the present invention, an electronic element mounted on the second circuit board, and a lid that covers the electronic element. And the said electronic element is mounted in the metal member of the 2nd circuit board of this invention mentioned above. Therefore, according to the second electronic component of the present invention, as with the first electronic component of the present invention described above, the air tightness of the electronic component can be improved.

 [0040] In the second electronic component of the present invention, the distance between the electronic element and the conductive film is preferably in the range of 30 to 50 µm. This is because it is possible to reduce the thickness of the electronic component while securing the operation space of the electronic element.

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

 [0042] [First embodiment]

First, a first embodiment of the present invention will be described with reference to the drawings. Refer to Figure 1A 1 is a cross-sectional view of a circuit board according to a first embodiment of the present invention. FIG. 1B to be referred to is a schematic plan view of the circuit board according to the first embodiment of the present invention. The circuit board according to the first embodiment is an example of the first circuit board of the present invention described above.

As shown in FIG. 1A, the circuit board 1 according to the first embodiment is insulated from the first main surface 10a of the insulating substrate 10 and the insulating substrate 10 formed in the thickness direction of the insulating substrate 10. A through hole 11 for connecting the second main surface 10 b of the substrate 10, a first conductive film 12, a second conductive film 13, and the through hole 11 are filled and joined to the first conductive film 12. Metal member 14. The first conductive film 12 includes an electron element connection electrode 12a formed around the opening of the through hole 11 on the first main surface 10a, a connection conductive film 12b formed on the inner wall of the through hole 11, and a second main film 10a. It consists of an external connection electrode 12c formed around the opening of the through hole 11 on the surface 1 Ob. The first conductive film 12 corresponds to the “conductive film” recited in the claims.

[0044] Since the metal member 14 is made of a metal material such as gold or copper, for example, heat treatment at a high temperature (for example, 750 ° C or higher) is not required when the metal member 14 is bonded to the first conductive film 12. As a result, the circuit board 1 can be thinned and the manufacturing cost can be reduced. Further, the metal member 14 is formed in a substantially spherical shape. As a result, the connection between the connection conductive film 12b formed on the inner wall of the through hole 11 and the metal member 14 can be performed uniformly.

 As shown in FIG. 1B, the second conductive film 13 is formed on the outer edge portion of the first main surface 10a of the insulating substrate 10. The second conductive film 13 serves as an adhesive surface with a lid, which will be described later, when an electronic component is manufactured using the circuit board 1.

 Further, as shown in FIG. 1A, the diameter of the through hole 11 gradually decreases from the first main surface 10a to the second main surface 10b. Thereby, the metal member 14 can be filled easily. In addition, a recess 10c is formed in the first main surface 10a. Thereby, when the circuit board 1 is applied to an electronic component, it becomes easy to secure an operation space of an electronic element described later.

 [0047] [Second Embodiment]

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 2 to be referred to is a cross-sectional view of an electronic component according to the second embodiment of the present invention. The electronic component according to the second embodiment includes the circuit board 1 according to the first embodiment described above. Therefore, in Figure 2, Figure 1 and The same components are denoted by the same reference numerals, and the description thereof is omitted. The electronic component according to the second embodiment is an example of the first electronic component of the present invention described above.

 As shown in FIG. 2, the electronic component 2 according to the second embodiment includes the circuit board 1 according to the first embodiment described above, the electronic element 20 mounted on the circuit board 1, and the electronic element 20. Covering lid 21 and The lid 21 has a concave portion 21a formed using a sandblasting method or an etching method. The electronic element 20 is mounted on the electronic element connection electrode 12a via the conductive adhesive 22. In addition, the second conductive film 13 and the lid 21 are bonded via an adhesive layer 23. As a constituent material of the adhesive layer 23, a gold-tin plating film, a gold-tin paste, low-melting glass, or the like can be used. Thus, since the electronic component 2 according to the second embodiment uses the circuit board 1 according to the first embodiment of the present invention described above, the airtightness of the electronic component 2 can be improved.

 Further, a recess 10 c is formed in a region of the first main surface 10 a of the insulating substrate 10 facing the electronic element 20. Thereby, it becomes easy to secure an operation space of the electronic element 20 (between the lid 21 and the first main surface 10a). When a crystal piece is used as the electronic element 20, it is preferable that the distance between the lid 21 and the first main surface 10a be 200 / zm or more. In that case, the depth of the recess 10c may be about 30 to 50 μm.

 [0050] In addition, when a crystal piece is used as the electronic element 20, the lid body can perform frequency adjustment by irradiating the crystal piece with a laser even after the electronic element 20 is covered with the lid body 21. It is preferable to use the glass having high laser transmittance as the constituent material 21. When a light emitting diode is used as the electronic element 20, it is preferable to use glass as a constituent material of the lid body 21 because it has a high visible light transmittance.

 Next, an example of a method for manufacturing the electronic component 2 according to the second embodiment will be described with reference to the drawings. 3A to J to be referred to are process sectional views showing an example of a method for manufacturing the electronic component 2 according to the second embodiment. 3A to 3G are process cross-sectional views illustrating an example of a method for manufacturing the circuit board 1 according to the first embodiment described above. 3A to 3J, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof is omitted.

[0052] First, as shown in FIG. 3A, the thermal expansion coefficient of ^{3 X 10- 6 Z ° C~8 X} 10- 6 Z alkali-free glass force ° C is also an insulating substrate 10 (thickness: 0.99 m) prepared To do. Next, as shown in FIG. 3B, a recess 10c having a depth of 30 to 50 / zm is formed on the first main surface 10a of the insulating substrate 10 by sandblasting.

 Subsequently, as shown in FIG. 3C, through-holes 11 are formed from the first main surface 10a side of the insulating substrate 10 by the sandblast method. At this time, the through hole 11 is preferably formed so that the diameter of the through hole 11 gradually decreases from the first main surface 10a to the second main surface 10b. In this case, the opening diameter of the through hole 11 may be, for example, 120 m on the first main surface 10a side and 80 m on the second main surface 10b side.

 Next, as shown in FIG. 3D, a conductive film 7 is formed on the surface of the insulating substrate 10 and the inner wall of the through hole 11. For example, a chromium thin film (thickness: 0.1 μm) is formed on the surface of the insulating substrate 10 and the inner wall of the through hole 11 by a sputtering method, and a palladium thin film (thickness: 0) is formed on the chromium thin film by a sputtering method. 05 / zm), a gold thin film (thickness: 0.5 to 1.0 m) is formed on the palladium thin film by an electrolytic plating method. A conductive film 7 made of a thin film can be formed.

 Next, after a resist film (not shown) is formed at a predetermined location on the conductive film 7, the portion on the conductive film 7 not covered with the resist film is etched, as shown in FIG. 3E. First and second conductive films 12 and 13 are formed.

 [0057] Next, a heater (300 ° C heating temperature) in a reducing atmosphere (N gas, etc.)

 2

Set the insulating substrate 10 on the notch (not shown) with a holding guide (not shown), and use the vertical movement type tool 6 (see Fig. 3F) built into the bonding head (not shown) of the wire bonder. Arrange it directly above the through hole 11. The alignment at this time can be performed by a position recognition device provided in the wire bonder. The positional accuracy at this time is, for example, ± 5 m or less. Further, a metal wire 5 (see FIG. 3F) is inserted into the clearance tool 6. As a constituent material of the metal wire 5, gold having high corrosion resistance is preferable. Then, the tip portion of the metal wire 5 is heated and melted with a torch (not shown) to form a substantially spherical metal member 14 (see FIG. 3F). The diameter of the metal member 14 is about 3 to 4 times that of the metal wire 5. Therefore, for example, when the metal member 14 has a diameter of about 120 / zm, the metal wire 5 having a diameter of about 38 m may be used. The metal member 14 generates a spark discharge between the tip of the metal wire 5 and a torch (not shown). It is formed from cocoon that can be born.

 Next, as shown in FIG. 3F, the first tool 6 is lowered, and the metal member 14 is filled into the through hole 11 while being pressed with a load of 100 to 300 gf. At this time, the ultrasonic vibration is supported in the Y direction in FIG. 1B for the tool 6 and at the same time the mechanical vibration in the X direction in FIG. The ultrasonic oscillation frequency at this time is preferably 60 to 120 kHz, and the ultrasonic application time is preferably 10 to 50 ms. Further, as a method for measuring mechanical micro-vibration, for example, there is a method of vibrating the bonding head in the X direction. The vibration width in the X direction at this time is preferably about the same as the vibration width of ultrasonic waves (for example, 5 to: LO m). In this way, the metal member 14 and the connection conductive film 12b are joined. After this, the lift tool 6 is raised and the metal wire 5 is cut. As a result, the circuit board 1 shown in FIG. 3G is obtained. When cutting the metal wire 5 by heating with a torch (not shown), a substantially spherical metal member 14 is formed simultaneously with the cutting, so that the circuit board 1 is continuously manufactured. Workability is improved. In this embodiment, since the ultrasonic combined thermocompression method as described above is used, the connection conductive film 12b and the metal member 14 are firmly bonded. Therefore, as described later, when the electronic component 2 (see FIG. 3J) is formed, the through-hole 11 is highly sealed, so that the electronic component 2 with high airtightness can be obtained.

 Subsequently, as shown in FIG. 3H, the electronic device 20 is mounted on the electronic device connection electrode 12a of the circuit board 1 via the conductive adhesive 22. As a result, the external connection electrode 12c of the circuit board 1 is electrically connected to the electronic element 20 via the connection conductive film 12b, the electronic element connection electrode 12a, and the conductive adhesive 22. In the present embodiment, a crystal piece is used as the electronic element 20.

[0060] Next, after the circuit board 1 is set on a positioning jig (not shown) in a vacuum atmosphere, the lid 21 is aligned directly above the circuit board 1 (see FIG. 31). And circuit board 1 are bonded together. At this time, as shown in FIG. 31, an adhesive layer 23 is provided in advance at the connection portion between the lid 21 and the circuit board 1. In this embodiment, a gold-tin alloy (thickness: 10 to 15 m) formed by electrolytic plating is used as the adhesive layer 23. In this case, if the mass ratio of gold-tin alloy (gold: tin) is, for example, 4: 1. [0061] Next, N 2 gas atmosphere of 290 to 310 ° C was applied while the lid 21 was pressurized with 5 X 10 ^{4 to} 6 X 10 ⁴ Pa.

 2 Heat together with circuit board 1 in a furnace. The heating time at this time is preferably 30 to 60 seconds. As a result, the circuit board 1 and the lid 21 are joined by the adhesive layer 23, and the electronic component 2 having high airtightness is obtained (FIG. 3J). The electronic component 2 shown in FIG. 3J has dimensions of 2. Omm and 1.6 mm and a thickness of 0.5 mm in the long and short cylinder directions, respectively, but the thickness is 0.5 mm. Can be manufactured at low cost. For example, electronic parts having dimensions of 1.6 mm and 1. Omm and a thickness of 0.4 mm can be manufactured at a low cost.

 [0062] [Third embodiment]

 Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 4 to be referred to is a cross-sectional view of a circuit board according to the third embodiment of the present invention. The circuit board according to the third embodiment is an example of the above-described second circuit board of the present invention. In FIG. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

 As shown in FIG. 4, in the circuit board 3 according to the third embodiment, the circuit board 1 according to the first embodiment is placed in the through hole l ib of the two through holes 1 la and l ib ( The metal member 14 is filled as in FIG. 1A. On the other hand, in the through hole 11 a, the opening on the first main surface 1 Oa side is closed with the metal member 30. The metal member 30 is formed in a substantially hemispherical shape, and the hemispherical surface and the first conductive film 12 are joined. Further, no recess is formed on the first main surface 10a. Others are the same as the circuit board 1 (refer FIG. 1A) which concerns on 1st Embodiment mentioned above. By having the above configuration, the circuit board 3 according to the third embodiment can exhibit the same effects as the circuit board 1 according to the first embodiment described above.

[0064] Further, according to the circuit board 3 according to the third embodiment, an electronic element can be directly mounted on the flat surface portion 30a of the metal member 30 without using a conductive material or the like. When applied, electronic components can be easily made thinner. In the through holes 11a and l ib shown in FIG. 4, the diameter gradually decreases from the first main surface 10a to the second main surface 10b, but the diameter of the through holes 11a and l ib does not gradually decrease. May be. That is, the opening force on the first main surface 10a side of the through holes 11a, ib may be reduced by the same force vj as the opening diameter on the second main surface 10b side of the through holes 11a, ib. [0065] [Fourth Embodiment]

 Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 5 to be referred to is a cross-sectional view of an electronic component according to the fourth embodiment of the present invention. The electronic component according to the fourth embodiment includes the circuit board 3 according to the third embodiment described above. Note that the electronic component according to the fourth embodiment is an example of the second electronic component of the present invention described above. In FIG. 5, the same components as those in FIGS. 2 and 4 are denoted by the same reference numerals, and the description thereof is omitted.

 [0066] As shown in FIG. 5, the electronic component 4 according to the fourth embodiment is different from the electronic component 2 according to the second embodiment described above (see FIG. 2) as a circuit board according to the third embodiment. This is the same as the electronic component 2 according to the second embodiment except that the substrate 3 is used and the electronic element 20 is directly mounted on the metal member 30. Therefore, the electronic component 4 according to the fourth embodiment has the same effect as the electronic component 2 according to the second embodiment described above, and the electronic element 20 is mounted without using a conductive material or the like. Therefore, it is possible to easily reduce the thickness. In order to secure an operating space for the electronic element 20, the distance between the electronic element 20 and the electronic element connection electrode 12a is preferably in the range of 30-50 μm.

 Next, an example of a method for manufacturing the electronic component 4 according to the above-described fourth embodiment will be described with reference to the drawings. 6A to 6D to be referred to are process sectional views showing an example of a method for manufacturing the electronic component 4 according to the fourth embodiment. 6A and 6B are process cross-sectional views illustrating an example of a method for manufacturing the circuit board 3 according to the above-described third embodiment. 6A to 6D, the same components as those in FIGS. 4 and 5 are denoted by the same reference numerals, and the description thereof is omitted.

 First, an insulating substrate 10 provided with through-holes 11a, l ib and first and second conductive films 12, 13 is prepared by performing the same steps as in FIGS. Figure 6A).

 [0069] Next, the metal member 14 is filled into the through hole l ib by using the tool 6 (see FIG. 3F), and the connection conductive film 12b and the metal member 14 are joined in the same manner as in the process of FIG. 3F described above. (Figure 6B).

[0070] Subsequently, the opening portion on the first main surface 10a side of the through hole 11a is closed with a substantially spherical metal member 30 using a milling tool 6 (see FIG. 3F), and the first conductive film 12 and the metal member are closed. 30 is joined (not shown). At this time, by pressing the metal member 30 with a load of 100 to 300 gf, the metal member 30 formed into a substantially spherical shape by using the chiral tool 6 is as shown in FIG. 6B. Thus, a substantially hemispherical metal member 30 is obtained. At this time, as the metal wire 5 (see FIG. 3F) inserted through the tool 1 for the drill, for example, when the opening diameter on the first main surface 10a side of the through hole 11a is about 120 m, the diameter is 51 μm. What is about m should be used. Other conditions are the same as those in the process of FIG. 3F described above. In this way, the circuit board 3 shown in FIG. 6B is obtained.

 Subsequently, as shown in FIG. 6C, the electrode portion of the electronic element 20 is formed on the metal member 30 of the circuit board 3.

 After stacking (not shown), the electronic member 20 is mounted by joining the metal member 30 and the electrode portion by a thermocompression bonding method using ultrasonic waves. Then, the electronic component 4 shown in FIG. 6D is obtained by performing the same steps as those shown in FIGS.

[0072] Unsaturated steam pressurization test according to IEC (International Electrotechnical Commission: International Electrotechnical Commission) 68-2- 66 (Test conditions: 130 ° C, 85% relative humidity (RH)) , 40 hours) after exposure to high humidity conditions, the result of an airtightness test (100 each) confirmed that the airtightness of the electronic component 4 was good. Here, “good airtightness” refers to a state in which the leak rate of 1 X 1CT ⁹ Pa 'n ^ Zsec or less can be maintained in an airtightness tester using helium as the tracer gas. The above airtightness test is a test based on JISZ2331 “Helium leak test method (vacuum spraying method)”, and was performed using a helium leak detector manufactured by ULVAC, Inc. as an airtightness tester.

 Industrial applicability

[0073] The present invention is useful for an electronic component including a quartz piece or a semiconductor element, and particularly useful for an electronic component that requires high airtightness.

Claims

The scope of the claims  [1] A circuit board including an insulating substrate and a through hole formed in the thickness direction of the insulating substrate for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate. So,  A conductive film formed on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;  A circuit board comprising: a metal member filled in the through hole and bonded to the conductive film. [2] The circuit board according to [1], wherein the diameter of the through hole gradually decreases from the first main surface to the second main surface. 3. The circuit board according to claim 1, wherein the metal member is formed in a substantially spherical shape. [4] A circuit board including an insulating substrate and a through hole formed in the thickness direction of the insulating substrate for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate. So,  A conductive film formed on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;  A circuit board comprising: a metal member that closes an opening of the through hole on the first main surface side and is in contact with the conductive film. [5] The metal member is formed in a substantially hemispherical shape,  5. The circuit board according to claim 4, wherein the hemispherical surface of the metal member and the conductive film are joined.  6. The circuit board according to claim 1, wherein the insulating substrate is a glass substrate. 7. The circuit board according to claim 1, wherein the insulating substrate is formed in a sheet shape.  [8] A through hole is formed in the thickness direction of the insulating substrate to connect the first main surface of the insulating substrate and the second main surface of the insulating substrate; Forming a conductive film on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces; A method of manufacturing a circuit board, comprising filling a through-hole with a substantially spherical metal member and bonding the metal member and the conductive film.  [9] A through hole is formed in the thickness direction of the insulating substrate to connect the first main surface of the insulating substrate and the second main surface of the insulating substrate;  Forming a conductive film on the inner wall of the through hole and around the opening of the through hole in the first and second main surfaces;  A method of manufacturing a circuit board, wherein an opening on the first main surface side of the through hole is closed with a substantially spherical metal member, and the metal member and the conductive film are joined. [10] The method for manufacturing a circuit board according to [8] or [9], wherein the insulating substrate is a glass substrate.  11. The method for manufacturing a circuit board according to claim 8, wherein the insulating substrate is formed in a sheet shape. [12] The invention according to claim 8 or claim 8, wherein, when joining the metal member and the conductive film, the ultrasonic wave is applied to the joining portion between the metal member and the conductive film while applying heat and a load. Item 10. A method for manufacturing a circuit board according to Item 9. [13] A circuit board including an insulating substrate, and a through hole formed in the thickness direction of the insulating substrate for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate; An electronic element mounted on the circuit board;  An electronic component including a lid that covers the electronic element,  The circuit board includes a conductive film formed on an inner wall of the through hole and around the opening of the through hole in the first and second main surfaces, and is filled in the through hole and bonded to the conductive film. A metal member,  The electronic component is mounted on the conductive film formed around the opening in the first main surface via a conductive material. [14] The electronic component according to claim 13, wherein a recess is formed in a region of the first main surface facing the electronic element. [15] A circuit board including an insulating substrate, and a through hole formed in the thickness direction of the insulating substrate for connecting the first main surface of the insulating substrate and the second main surface of the insulating substrate; , Electronic elements mounted on the circuit board;  An electronic component including a lid that covers the electronic element,  The circuit board includes a conductive film formed on an inner wall of the through hole and around the opening of the through hole in the first and second main surfaces, and an opening on the first main surface side in the through hole. The electronic component is mounted on the metal member, and a metal member that joins the conductive film. The electronic component according to claim 15, wherein a distance between the electronic element and the conductive film is 30 to 50 μm.