JPH08293752A - Surface mount electronic parts and manufacture of the same - Google Patents

Abstract

PURPOSE: To provide surface mount electronic parts and manufacturing method of the same, which can be miniaturized by improving soldering at the time of mounting. CONSTITUTION: Plural fitting electrodes 13 and 14 are formed on the front and rear faces of an alumina substrate 10, electronic part elements 20 are mounted on fitting electrodes on the front or rear side, and plural recessed grooves 11 and 12 continued in the direction of thickness are formed at the side edge parts of the alumina substrate 10. End face electrodes 15 and 16 for mutually conducting the fitting electrodes 13 and 14 on the front and rear sides are formed on the inner faces of the recessed grooves 11 and 12 and dip soldered layers 17 and 18 are formed on these end face electrodes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount electronic component and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, as a surface mount type piezoelectric oscillator,
The one shown in FIG. 1 is known. This piezoelectric oscillator has a structure in which a piezoelectric element 4 is mounted on an alumina substrate 1 on which mounting electrodes 2 and 3 are formed, an alumina cap 5 is covered over the piezoelectric element 4, and an adhesive 6 is used for sealing. Attachment electrodes 2 and 3 above
Are formed in strips on the front and back surfaces, and the mounting electrodes 2,
3 are connected to each other by end face electrodes 7 and 8 formed on the side edges. The end surface electrodes 7 and 8 are formed on the inner surfaces of the concave grooves 1a and 1b formed on the side edges of the alumina substrate 1. The concave grooves 1a and 1b are provided for two purposes of forming end face electrodes 7 and 8 for connecting the attachment electrodes 2 and 3 on the front and back sides and securing a fillet when soldering to a circuit board.

[0003]

By the way, silver (Ag) is generally used for forming electrodes by printing. Conventionally, the material for the attachment electrodes 2 and 3 and the end face electrodes 7 and 8 on the front and back surfaces of the alumina substrate 1 is used. As the above, AgPd (Pd content: 0.5 to 20%) is used to prevent silver erosion during mounting and soldering.

However, the addition of palladium (Pd) to silver deteriorates the solderability, and the height of the fillet may not satisfy the target value. In addition, there is a method of plating on silver in order to improve solderability and prevent silver from being eaten away, but this method has a problem of increasing cost. Further, when the adhesive 6 for bonding the cap 5 to the alumina substrate 1 flows into the concave grooves 1a and 1b,
Solderability deteriorates. In order to prevent this, it is necessary to make the size of the alumina substrate 1 considerably larger than that of the cap 5, which makes it difficult to reduce the size of the product.

Therefore, an object of the present invention is to provide a surface mount type electronic component which is inexpensive and can improve solderability at the time of mounting, and a manufacturing method thereof. Another object of the present invention is to provide a surface mount type electronic component which can reduce the size of the substrate and can be miniaturized, and a manufacturing method thereof.

[0006]

In order to achieve the above object, the invention according to claim 1 has a plurality of mounting electrodes formed on the front and back surfaces of an insulating substrate, and an electronic component element on either of the front and back mounting electrodes. Is mounted, a plurality of recessed grooves extending in the thickness direction are formed on the side edge portion of the insulating substrate, end face electrodes for electrically connecting the front and back mounting electrodes to each other are formed on the inner surfaces of these recessed grooves, and the molten solder is formed on these end face electrodes. It is a surface mount electronic component in which a layer is formed. In the above electronic component, a piezoelectric element may be used as the electronic component element, an alumina substrate may be used as the insulating substrate, and a cap covering the piezoelectric element may be bonded onto the alumina substrate. Further, when a piezoelectric element is used as the electronic component element and a rectangular alumina substrate having concave grooves formed on both side edges is used as the insulating substrate, the first and second alumina substrates are used.
A mounting electrode and a third electrode therebetween, and a capacitance section is formed between the first mounting electrode and the third electrode and between the second mounting electrode and the third electrode. Good. Further, these three electrodes may be extended to the side edges of the alumina substrate so as to be electrically connected to the end face electrodes formed on the inner surface of the groove, and a cap covering the piezoelectric element may be bonded onto the alumina substrate. . According to a fourth aspect of the present invention, in a method of manufacturing a surface mount electronic component in which an electronic component element is mounted on an insulating substrate, a step of forming a plurality of through holes on an insulating mother substrate, the front and back surfaces of the mother substrate. A step of forming a plurality of mounting electrodes, a step of forming an end face electrode for conducting the front and back mounting electrodes on the inner surface of the through hole, a step of mounting an electronic component element on one of the front and back mounting electrodes of the mother substrate, Including a step of embedding a solder paste in the through hole, a step of melting the solder paste embedded in the through hole, and a step of dividing the mother substrate at a portion of the through hole to which the molten solder adheres to form an insulating substrate . In addition, after melting the solder paste embedded in the through holes and before dividing the mother board,
Blow air to the mother board to make holes in the molten solder,
A step of bringing the molten solder to the inner peripheral surface of the through hole may be added.

[0007]

According to the electronic component of the present invention, the end surface electrode is formed on the inner surface of the groove formed in the side edge portion of the insulating substrate, and the molten solder layer is formed on the end surface electrode. The solder adheres well to the molten solder layer, and a sufficient fillet height can be secured. Therefore, solderability becomes good. Further, according to the manufacturing method of the present invention, since the solder paste is embedded in the through holes at the stage of the mother substrate and the solder is melted, the mother substrate is divided, so that the inner surface of the groove is efficiently formed. A molten solder layer can be formed.

The present invention is not limited to piezoelectric components, but can be applied to other electronic components (for example, resistor networks, capacitor networks, etc.) as long as they are surface-mounted. In the present invention, the piezoelectric element includes a piezoelectric oscillator, a crystal oscillator, a piezoelectric filter, an LT filter, a ceramic discriminator, a trap element, a SAW element and the like. The insulating substrate includes a glass substrate, a glass epoxy substrate, etc. in addition to the alumina substrate. Further, an alumina cap or a metal cap can be used as the cap.

[0009]

FIG. 2 shows a surface mount piezoelectric oscillator according to a first embodiment of the present invention. This piezoelectric oscillator includes an insulating substrate 10
And an oscillator element 20 and a cap 30. The substrate 10 is a rectangular thin plate having a thickness of 0.3 to 0.7 mm formed by sheet-molding or tablet-molding alumina ceramics, and has four concave grooves 11 and 12 extending in the thickness direction on both side edges of its long sides. Has been formed. Board 1
Two strip-shaped attachment electrodes 13 and 14 are formed on the front and back surfaces of 0, and end surface electrodes 15 and 15 are formed on the inner surfaces of the concave grooves 11 and 12.
16 are formed. The mounting electrodes 13 and 14 formed on the front and back surfaces of the substrate 10 are connected to each other via the end surface electrodes 15 and 16. On the end surface electrodes 15 and 16 formed on the inner surfaces of the concave grooves 11 and 12, as shown in FIG.
18 (reference numeral 18 is not shown) is formed.

On the mounting electrodes 13 and 14, the oscillator element 20 is adhered and fixed by a material 19 having both conductivity and adhesiveness such as a conductive adhesive or solder. The oscillator element 20 of this embodiment is a known thickness-shear vibration mode oscillator, and as shown in FIG. 4, the piezoelectric substrate 21 made of piezoelectric ceramics or piezoelectric single crystal has a surface of about 2 mm from one end side.
The electrode 22 is formed over the region of / 3 and the electrode 23 is formed over the region of about 2/3 from the other end side of the back surface. One ends of the two electrodes 22 and 23 face each other at an intermediate portion with the piezoelectric substrate 21 interposed therebetween to form a vibrating portion. The conductive adhesive 1 so that this vibrating part does not come into contact with the substrate 10.
A certain space is secured by the thickness of 9. The other ends 22a and 23a of the electrodes 22 and 23 extend around the end surface of the piezoelectric substrate 21 to the other surface side. By bonding with the conductive adhesive 19 as described above, the resonator element 20
The electrodes 22 and 23 are electrically connected to the mounting electrodes 13 and 14, respectively. The electrode pattern of the oscillator element 20 is not limited to the above, and may be a pattern as shown in FIG. 5, the same parts as those in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted.

The cap 30 is adhered to the substrate 10 with an adhesive 25 so as to cover the oscillator element 20.
Although the cap 30 is formed by deep drawing a metal plate in a U-shaped vertical cross section, coining or die casting may be used. As the material of the cap 30, aluminum, aluminum alloy (A-5000 series), nickel silver (Ni · Cu)
Alloy), 42Ni-Fe alloy is used, but other materials may be used. As the adhesive 25, epoxy-based, epoxy-acrylate-based, and silicone-based adhesives can be considered from the viewpoint of heat resistance and chemical resistance, but the epoxy-based adhesive is preferable from the viewpoint of adhesiveness with the metal cap 30 and cost.
The oscillator element 20 made of a piezoelectric ceramic material has a property of depolarizing at a high temperature, but since the epoxy adhesive is usually cured at 200 ° C. or lower, the oscillator element 20 is not likely to depolate.

Next, a method of manufacturing the piezoelectric oscillator of the above embodiment will be described. First, a mother substrate 10A as shown in FIG.
To prepare. Through hole 1 is previously formed on the mother board 10A.
1A and 12A are formed in a line. The strip-shaped attachment electrodes 13 and 14 are formed on the front and back surfaces of the mother substrate 10A at positions facing each other, and the through holes 11 are formed.
End face electrodes 15 and 16 connecting the front and back attachment electrodes 13 and 14 are also formed on the inner surfaces of A and 12A. These electrodes 11
Known methods such as sputtering, vapor deposition, printing, and thermal spraying can be used for forming Nos. 14 to 14, but in this example, an Ag / Pd-based electrode material (Pd content: 0.5 to 2) is used.
0%) to a thickness of 5 to 20 μm, and 800 to 900
Firing was performed at ° C / 1 hour.

Next, the solder paste 17A is embedded in the through holes 11A and 12A (see FIG. 7A). The solder paste 17A is a mixture of solder and flux, and is embedded by a method such as metal printing, screen printing, or dispensing. Next, as shown in FIG. 8, the oscillator element 20 is mounted on the mother substrate 10A, and the cap 30 is bonded. In addition, in FIG. 8, one cap 30
However, only the oscillator element 20 and the cap 30 are provided on the mother substrate 10A at each element portion surrounded by the broken line CL.
Are glued together.

Next, the mother board 10A is inserted into a reflow soldering apparatus to melt the solder paste 17A embedded in the through holes 11A and 12A. This time,
As shown in FIG. 7B, the molten solder 17 closes the through holes 11A and 12A in a film shape by the surface tension,
There is no possibility that the water will flow down from the through holes 11A and 12A. Next, air is blown from above the mother substrate 10A in the state where the solder is melted to make a hole in the molten solder 17 (see FIG. 7C). As a result, the molten solder 17 is attracted to the inner surfaces of the through holes 11A and 12A due to the surface tension, and adheres to the end surface electrodes 15 and 16 in an annular shape with a uniform thickness.

After the solder is solidified, the mother substrate 10A is divided according to the broken line CL in FIG. 8 to obtain the piezoelectric oscillator shown in FIG. That is, the mother board 10A has through holes 11A,
Since it is divided at the position of 12A, the through hole 11A,
12A becomes concave grooves 11 and 12. At the time of cutting, the solder layers 17 and 18 are not in the film shape as in FIG.
As shown in FIG. 7C, since the solder is pulled toward the inner surfaces of the through holes 11A and 12A, the solder does not drop during the cutting, and the solder is accurately separated together with the mother board 10A (FIG. 7D. )reference).

In the above manufacturing method, the through holes 11, 1
Mother board 1 after embedding solder paste 17A in 2
Although the oscillator element 20 and the cap 30 are bonded to 0A and then the solder paste 17A is melted after that, instead of this, the oscillator element 20 and the cap 30 are bonded to the mother substrate 10A, and then the through hole 11 is formed. , 12 may be filled with the solder paste 17A, and then the solder paste 17A may be melted. In addition, through holes 11,
It is also possible to embed the solder paste 17A in 12 and melt the solder paste 17A, and then bond the oscillator element 20 and the cap 30 to the mother substrate 10A.

FIG. 9 shows a state in which the piezoelectric oscillator of the above embodiment is mounted on the circuit board P. As is clear from the figure, since the solder layer 17 is formed in advance on the end surface electrode 15 of the substrate 10, the solder layer 17 and the solder S at the time of mounting have good adhesion and have a sufficient height h. The fillet can be secured. Although FIG. 9 shows an example in which the solder layer 17 does not melt with the solder S, it may melt together. In addition, even if the adhesive 25 of the cap 30 slightly flows into the concave groove 11,
Since the solder layer 17 has already been formed on the inner surface of the groove 11, there is no fear that the solderability will deteriorate. As a result, it is not necessary to make the substrate 10 larger than necessary, and the product can be easily downsized.

FIG. 10 shows a second embodiment of the electronic component according to the present invention. In this embodiment, one oscillator element O used in a Colpitts type oscillation circuit and two capacitors C ₁ ,
This is a built-in capacitor type oscillator including C ₂ and its electric circuit is as shown in FIG.

Similar to the first embodiment, the substrate 40 is made of alumina ceramics, the first capacitance electrode 41 is formed at the center of the surface of the substrate 40, and the two mounting electrodes 42, 43 are provided at both ends of the surface. Are formed. The electrodes 41 to 43 having the same shape are formed on the back surface of the substrate 40. Both ends of the electrodes 41 to 43 are drawn to the recessed grooves 40a to 40c formed on both side edges of the substrate 40, and the front and back electrodes 41 are formed via the end surface electrodes 44 to 46 formed on the inner surface of the recessed groove 40a. ~ 43 are in conduction with each other. Although not shown in FIG. 10, a molten solder layer similar to that in FIG. 3 is formed on the inner surfaces of the concave grooves 40a to 40c, that is, on the end surface electrodes 44 to 46.

A dielectric layer 47 is formed on the first capacitance electrode 41 of the substrate 40 and on the portion corresponding to the cap bonding portion.
Are formed at a constant thickness and at the same time. Dielectric layer 47
The thickness of the electrode depends on the target capacitance value, but
Cap 5 which alleviates irregularities due to 1 to 43 and is described later
5 is set to a thickness that ensures sufficient insulation between the electrodes 5 and the electrodes 41 to 43. The dielectric layer 47 of this embodiment
In the above, the capacitor part 47a covering the first capacitor electrode 41 and the frame-shaped adhesive part 47b corresponding to the cap adhesive part are continuously formed. However, even if the capacitor part 47a and the adhesive part 47b are separated from each other. Good.

On the dielectric layer 47, two second capacitance electrodes 48 and 49 are formed by a known method such as sputtering, vapor deposition, printing and thermal spraying. These capacitance electrodes 48, 4
The main portion of 9 is opposed to the first capacitance electrode 41 with the capacitance portion 47a in between, and some of them are electrically connected to the attachment electrodes 42 and 43 through the window hole 47c.

On the second capacitance electrodes 48 and 49, a material 5 having both conductive and adhesive functions such as a conductive adhesive is used.
The oscillator element 50 is adhesively fixed by 7. The oscillator element 50 of this embodiment is also a thickness-shear vibration mode oscillator element similar to that of the first embodiment. That is, the piezoelectric substrate 5
The electrode 52 extends from one end of the surface of No. 1 to about 2/3 of the area.
Is formed, and the electrode 53 is formed over the area of about 2/3 from the other end side of the back surface. One end of each of the electrodes 52 and 53 faces the piezoelectric substrate 51 at an intermediate portion thereof to form a vibrating portion, and the vibrating portion is formed by the thickness of the conductive adhesive 57. A certain space is secured so as not to come into contact with. The other ends 52a and 53a of the electrodes 52 and 53 extend around the end surface of the piezoelectric substrate 51 to the other surface side. By bonding with the conductive adhesive 57 as described above, the electrodes 52, 53 of the oscillator element 50 are bonded.
Are electrically connected to the second capacitance electrodes 48 and 49, respectively.

The cap 55 is adhered to the substrate 40 by an adhesive 56 so as to cover the oscillator element 50.
As the material of the cap 55, the same material as in the first embodiment was used. The adhesive 56 is also made of the same material as in the first embodiment, applied to the bottom surface of the opening of the cap 55, and then adhered onto the dielectric layer 47 and cured.

Also in the case of this embodiment, in the manufacturing process, as shown in FIG.
Mother board 4 having a large number of through holes 58 such as
Use 0A. Capacitor electrodes 41 and attachment electrodes 42 and 43 are formed on the front and back surfaces of this mother substrate 40A by a known method such as printing, and end face electrodes 44 to 46 are formed on the inner surface of the through hole 58. The same electrode material as in the first embodiment is used. After that, a solder paste 59 is embedded in the through hole 58, and the dielectric layer 47 is formed on the mother substrate 40A, the second capacitance electrodes 48 and 49 are formed, the oscillator element 50 is mounted, and the cap 55 is bonded. Perform sequentially. FIG. 13 shows this state. Then, the solder paste 59 is reflowed, and air is blown to the melted solder in the same manner as in FIG. 7B to make a hole.
As a result, the molten solder adheres to the inner surface of the through hole 58 in a ring shape. After that, the mother substrate 40A is divided by the broken line CL on the through hole 58 to obtain a capacitance built-in oscillator as shown in FIG.

FIG. 14 shows a third embodiment of the piezoelectric component according to the present invention. This embodiment is also an oscillator with a built-in capacitor similar to the second embodiment. In the second embodiment, the dielectric layer 47 and the second capacitance electrode 4 are formed on the substrate 40 to form the capacitance portion.
8 and 49 are formed, this embodiment uses a separate capacitor element.

Similar to the first embodiment, the substrate 60 is made of alumina ceramics, and three attachment electrodes 61 to 63 are formed on the front and back surfaces of the central portion and both ends of the substrate 60. The end portions of the attachment electrodes 61 to 63 are drawn to the concave grooves 60a to 60c formed on both side edge portions of the substrate 60, and the end surface electrodes 64 to 66 formed on the inner surfaces of the concave grooves 60a to 60c.
The attachment electrodes 61 to 63 on the front and back sides are electrically connected to each other through. Inner surfaces of the concave grooves 60a to 60c, that is, the end surface electrodes 64 to
A molten solder layer (not shown) similar to that in FIG. 3 is formed on 66. The upper surface of the substrate 60 and the electrodes 61 to
On the upper side of 63, a frame-shaped insulator layer 67 corresponding to the cap bonding portion is formed with a constant thickness.

On the substrate 60, a material in which the oscillator element 70 and the capacitor element 60 are laminated and integrated by a material 90 to 92 having a conductive and adhesive function such as a conductive adhesive is fixedly adhered. Has been done. The oscillator element 70 of this embodiment is also a thickness-shear vibration mode oscillator element similar to that of the first embodiment. That is, as shown in FIG. 15, the electrode 72 is formed from one end side of the surface of the piezoelectric substrate 71 to a region of about 2/3, and the electrode 73 is formed from the other end of the back surface to a region of about 2/3. Are formed. One ends of the electrodes 72, 73 oppose each other with the piezoelectric substrate 71 interposed therebetween at an intermediate portion thereof to form a vibrating portion. The other ends 72a and 73a of the electrodes 72 and 73 extend around both end surfaces of the piezoelectric substrate 71 to the other surface side.

Further, as shown in FIG. 16, two capacitor elements 80 extend from both ends toward the center on the surface of a dielectric substrate (for example, a ceramic substrate) 81 having the same length and width as the oscillator element 70. Individual electrodes 82, 83 are formed, and one common electrode 84 facing the individual electrodes 82, 83 is formed on the back surface.
Two capacitive parts are formed at the facing part of 3 and the common electrode 84. The end portions 82a, 83a of the individual electrodes 82, 83
Wrap around to the back surface side through both end surfaces of the dielectric substrate 81.

The back surface of the oscillator element 70 and the capacitor element 8
The surface of 0 is adhered and fixed at both ends by materials 93 and 94 having a conductive and adhesive function such as a conductive adhesive. At this time, a predetermined vibration space is formed between the vibrating portion of the oscillator element 70 and the capacitor element 80 due to the thickness of the materials 93 and 94. In this way, one electrode 73 of the oscillator element 70 and one individual electrode 82 of the capacitor element 80 are connected, and the other electrode 7
2 and the other individual electrode 83 are connected. Damping materials 95 and 96 made of resin or the like for frequency adjustment are applied to both ends of the surface of the oscillator element 70.

After the oscillator element 70 and the capacitor element 80 are integrally bonded, the back surface side of the capacitor element 80 is bonded to the substrate 60 with the materials 90 to 92, and the end portion 82a of one individual electrode 82 of the capacitor element 80 is bonded. Is the attachment electrode 61, and the end portion 83a of the other individual electrode 83 is the attachment electrode 6
3, the common electrode 84 is connected to the attachment electrode 62, respectively.

The cap 100 is adhered to the substrate 60 with an adhesive 101 so as to cover the oscillator element 70 and the capacitor element 80. As the material of the cap 100, the same material as in the first embodiment was used. Adhesive 10
1 also uses the same material as in the first embodiment, and uses the cap 100
After being applied to the bottom surface of the opening of the above, it was adhered on the insulator layer 67 and cured.

Also in the case of this embodiment, the manufacturing method is as shown in FIG.
It is almost the same as 13. That is, a mother substrate 60A having a large number of through holes 68 as shown in FIG. 17 is prepared, the attachment electrodes 61 to 63 are formed on the front and back surfaces of this mother substrate 60A by a known method such as printing, and the through holes 68 are formed. The end surface electrodes 64-66 are formed on the inner surface. afterwards,
The solder paste 69 is embedded in the through hole 68,
Formation of the insulator layer 67 on the mother substrate 60A, mounting of the oscillator element 70 and the capacitor element 80, the cap 10
Adhesion of 0 and the like are sequentially performed. FIG. 18 shows this state. Then, the solder paste 69 is reflowed, and air is blown to the melted solder to make a hole. As a result, the molten solder adheres to the inner surface of the through hole 68 in a ring shape. After that, the mother board 60A is set to the through hole 68.
By dividing along the line, a capacitor built-in type oscillator as shown in FIG. 14 is obtained.

[0033]

As is apparent from the above description, according to the present invention, the end face electrode is formed on the inner surface of the groove formed in the side edge portion of the insulating substrate, and the solder layer is formed on the end face electrode. Therefore, the solderability at the time of mounting becomes good, and a fillet having a sufficient height can be formed. In particular, since the solder layer is a molten solder rather than a solder paste, it has good adhesion to the end face electrodes, and the solderability does not deteriorate even if AgPd is used as the material of the end face electrodes to prevent solder erosion. Moreover, there is no need to plate the end face electrodes, and the structure can be constructed at low cost. Further, when the cap is adhered to the substrate, if the adhesive flows into the groove, the solderability is deteriorated. However, in the present invention, since the solder layer is formed on the inner surface of the groove, some adhesive may It does not deteriorate the solderability even if it flows into the groove. Therefore, it is not necessary to increase the size of the substrate, and the product can be easily downsized. Further, according to the manufacturing method of the present invention, since the solder paste is embedded in the through hole at the stage of the mother substrate and the solder is melted, the mother substrate is divided, so that the inner surface of the concave groove can be easily formed. A molten solder layer can be formed.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a conventional surface mount piezoelectric oscillator.

FIG. 2 is an exploded perspective view of the surface mount piezoelectric oscillator according to the first embodiment of the present invention.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a front and back view of an oscillator element used in the piezoelectric oscillator of FIG.

FIG. 5 is a front and back view of another example of the oscillator element.

FIG. 6 is a perspective view of a mother substrate for manufacturing the piezoelectric oscillator of FIG.

FIG. 7 is an explanatory diagram showing a method of forming a molten solder layer in the piezoelectric oscillator of FIG.

8 is a perspective view showing a state in which a solder paste is embedded in a through hole of the mother board of FIG. 6 and a cap is adhered to the mother board.

9 is a sectional view of the piezoelectric oscillator of FIG. 2 mounted on a circuit board.

FIG. 10 is an exploded perspective view of a built-in capacitor type piezoelectric oscillator according to a second embodiment of the present invention.

11 is a circuit diagram of the piezoelectric oscillator shown in FIG.

FIG. 12 is a perspective view of a mother substrate for manufacturing the piezoelectric oscillator of FIG.

13 is a perspective view showing a state in which a solder paste is embedded in a through hole of the mother board of FIG. 12 and a cap is adhered to the mother board.

FIG. 14 is an exploded perspective view of a built-in capacitor type piezoelectric oscillator according to a third embodiment of the present invention.

15 is a front and back view of an oscillator element used in the piezoelectric oscillator of FIG.

16 is a front and back view of a capacitor element used in the piezoelectric oscillator of FIG.

17 is a perspective view of a mother substrate for manufacturing the piezoelectric oscillator of FIG.

18 is a perspective view showing a state in which a solder paste is embedded in a through hole of the mother board of FIG. 17 and a cap is attached to the mother board.

[Explanation of symbols]

 10 Substrate 11,12 Recessed groove 13,14 Mounting electrode 15,16 End surface electrode 17,18 Melted solder layer 20 Piezoelectric element 30 Cap

Claims (5)

[Claims] 1. A plurality of mounting electrodes are formed on the front and back surfaces of an insulating substrate, an electronic component element is mounted on one of the front and back mounting electrodes, and a plurality of concave grooves extending in the thickness direction are formed on the side edges of the insulating substrate. An end surface electrode is formed on the inner surface of these recesses for electrically connecting the front and back mounting electrodes to each other, and a molten solder layer is formed on these end surface electrodes. 2. The surface mount electronic component according to claim 1, wherein the electronic component element is a piezoelectric element, the insulating substrate is an alumina substrate, and a cap covering the piezoelectric element is provided on the alumina substrate. A surface-mount type electronic component characterized by being bonded. 3. The surface mount electronic component according to claim 1, wherein the electronic component element is a piezoelectric oscillator element, and the insulating substrate is a rectangular alumina substrate having concave grooves formed on both side edges. The alumina substrate is provided with first and second attachment electrodes and a third electrode therebetween, and between the first attachment electrode and the third electrode and between the second attachment electrode and the third electrode. And a capacitance portion is formed between the three electrodes, and the three electrodes are extended to the side edge portion of the alumina substrate so as to be electrically connected to the end face electrodes formed on the inner surface of the concave groove. Is a surface-mounted electronic component characterized in that a cap covering the piezoelectric element is bonded. 4. A method of manufacturing a surface mount type electronic component in which an electronic component element is mounted on an insulating substrate, the step of forming a plurality of through holes in an insulating mother substrate, a plurality of attachments on the front and back surfaces of the mother substrate. A step of forming an electrode, a step of forming an end surface electrode for conducting the front and back mounting electrodes on the inner surface of the through hole, a step of mounting an electronic component element on one of the front and back mounting electrodes of the mother board, a through hole A surface mount type electronic device including a step of embedding a solder paste, a step of melting the solder paste embedded in the through hole, and a step of cutting the mother substrate at a portion of the through hole to which the molten solder adheres to form an insulating substrate. Manufacturing method of parts. 5. The manufacturing method according to claim 4, wherein after the solder paste embedded in the through holes is melted and before the mother substrate is divided, air is blown to the mother substrate to form holes in the molten solder. A method of manufacturing a surface mount electronic component, comprising the steps of opening and bringing molten solder to an inner peripheral surface of a through hole.