JPH0340508B2 - - Google Patents

Description

[Detailed Description of the Invention] [Table of Contents] ● Overview ● Industrial fields of application ● Conventional technology (Figures 5 and 6) ● Problems to be solved by the invention ● Means for solving the problems ● Effects ● Embodiment (Figs. 1, 2, 3, 4) ● Effects of the invention [Summary] It is an insulating hermetic seal type leadless package in which the connecting flat part 18a of the electrode body 18 is made of glass. 6, and at least the flat portion 18 of the glass 6.
A notch 6a is provided in a portion corresponding to a, and the flat part 18a and a part of the electrode body vertical part 18b adjacent to the flat part 18a are exposed from the glass 6 in the notch 6a, and the vertical part 18b is exposed from the glass 6. By providing a portion as the strain absorbing portion 18c,
The glass 6 is mounted on the printed wiring board 11 via the strain absorbing portion 18c without changing the mounting height from the conventional one.
As a result, glass 6
The difference in the amount of expansion or contraction between the glass 6 and the printed wiring board 11 is reliably absorbed by the strain absorbing portion 18c, so that the glass 6 and the printed wiring board 11 can individually and freely expand or contract without being restrained by each other. This made it possible.

[Industrial application field]

The present invention is an insulating hermetic seal for housing a crystal oscillator (crystal element), an integrated circuit (IC) board, a composite element circuit board, other elements, etc.
The present invention relates to a type of leadless package, and particularly to the structure of incorporating an electrode body thereof.

Traditionally, hermetic type package cages have been formed with a plurality of lead wires extending downward from the package body. It was inserted into a small hole and soldered on the back side of a printed wiring board using an automatic soldering device or the like. In this type of package, it is necessary to make small holes in the printed wiring board.
There are problems such as the small holes not being filled with solder enough and electrical continuity being impaired, and the fused interface between the lead wire and the glass breaking due to unintentional force being applied when correcting a bend in the lead wire. In the case of multiple leads, there was also the problem that it was difficult to insert the leads into the printed wiring board due to lead deformation.

Therefore, in recent years, leadless packages have been developed that have electrodes on the bottom surface of the package and can be connected directly to the printed wiring board.
This leadless package has come into widespread use.

[Conventional technology]

FIG. 5 shows a conventional leadless package, in which a is a perspective view (partially cut away) and b is a
FIG. 6 is a cross-sectional view taken along line A ₁ -A ₂ of FIG.

As shown in Fig. 5, the container body 1 is press-molded from a metal plate into a rectangular planar shape, and has a flange portion 3 on the periphery for attaching the lid 2, and a flat surface in the center. A recessed region 4 having a rectangular shape is provided. This recessed area 4 has a bottom wall 4a,
The bottom wall 4a has four small holes 5, 5 for inserting the electrode body.
A is formed through the hole. These small holes 5, 5a
Three of the small holes 5 are formed to have a relatively large hole diameter, and one small hole 5a is formed to have a relatively small hole diameter. The glass 6 has concave portions made of glass powder that correspond to the outer and lower surfaces of the concave area 4 of the vessel body 1, and has small through holes (not shown) at positions corresponding to the small holes 5 and 5a of the vessel body 1. It is pre-press-molded into a block shape with a Then, this block-shaped glass 6 is fitted into the container body 1 from below, and then the electrode body 8 is inserted into the four small holes 5, 5a.
This assembly is housed in a carbon jig (not shown), and a conductive material ( For example, a hermetic seal type leadless package 10 as shown in FIG. 5B is obtained by adding a silver solder 7 and heating and welding the glass 6 and the conductive material 7 in a heating furnace (not shown).

As shown in FIG. 5b, the glass 6 is sealed from the lower surface of the bottom wall 4a of the vessel 1 to the outer surface of the side wall 4b. On the other hand, the electrode body 8 has a connecting flat part 8a that is welded to the lower surface of the glass 6.
, and extends onto the container body 1 through the small holes 5 and 5a of the container body 1. The other electrode bodies 8 except for the ground electrode body passing through the small hole 5a are insulated from the vessel body 1 through the glass 6, and the ground electrode body 8 passing through the small hole 5a is insulated from the body body 1 through the conductive material 7. 1 is electrically connected to. Package 10 after completion
After the crystal element, IC board, composite element circuit board, and other elements are mounted and connected to the electrode body 8,
The lid 2 is attached to the vessel body 1 by a method such as resistance welding.

The package 10 formed in this way has the sixth
As shown in the figure, it is mounted on a printed wiring board 11. In FIG. 6, reference numeral 12 indicates a conductor pattern provided on the printed wiring board 11, and 13
indicates solder. When mounting the package 10 on the printed wiring board 11, solder 13 is applied in advance to either the conductor pattern 12 or the connection flat part 8a, and the flat part 8a is applied onto the conductor pattern 12.
package 1 by arranging them in alignment and heating them in a heating furnace (not shown) to melt the solder 13.
0 is soldered onto the printed wiring board 11. In this conventional example, the glass 6 is directly attached to the printed wiring board 11 via the flat part 8a, so the glass 6 and the printed wiring board 11 are directly mechanically restrained from each other. .

[Problem that the invention seeks to solve]

In the above conventional example, since the glass 6 is directly attached to the printed wiring board 11 via the electrode body 8 (flat portion 8a), the glass 6 and the printed wiring board 11 are directly restrained from each other. Therefore, glass 6 and printed wiring board (substrate material) 11
Concentrated stress acts due to the difference in the amount of thermal expansion (or amount of contraction during cooling) due to the difference in the coefficient of thermal expansion of
There are problems in that cracks in the soldered portion, peeling and disconnection of the conductor pattern 12, destruction of the fused interface between the electrode body 8 and the glass 6, and cracks in the glass 6 itself are likely to occur. In particular, when the base material of the printed wiring board 11 is a resin material, the above problem is likely to occur because of a large difference in coefficient of thermal expansion.

The present invention was created in view of these problems, and provides a leadless package that can solve the above problems even when the glass used in the package and the printed wiring board have large coefficients of thermal expansion. The purpose is to

[Means for solving problems]

As a means for solving the above problems, the present invention, as illustrated in FIG. 1, comprises: a container body 1 made of a metal plate and having a flange portion 3 around it for attaching a lid 2; a glass 6 as an insulating material provided on at least the lower surface of the glass 6; and a connecting flat part 18a disposed on the lower surface 6b side of the glass 6; a vertical section 18 extending over the body 1;
In a leadless package in which a plurality of electrode bodies 18 having an electrode body 18 and a plurality of electrode bodies 18 are sealed airtightly and insulated, the flat part 18a of the electrode body 18 is
A notch portion 6a is provided in at least a portion of the glass 6 corresponding to the flat portion 18a, and the notch portion 6a is adjacent to the flat portion 18a and the flat portion 18a. A part of the vertical part 18b is exposed from the glass 6, and the part of the vertical part 18b is provided as a strain absorbing part 18c.

As illustrated in FIG. 1, the electrode body 18 has through holes 18d and 18e in both or one of its flat portion 18a and strain absorbing portion 18c.
It is preferable that it has.

Further, as illustrated in FIGS. 1 and 4, it is preferable that the electrode body 18 has an upwardly bent portion 18g or a downwardly bent portion 18h at the free end of its flat portion 18a.

[Effect]

According to the above means according to the present invention, the glass 6 can be indirectly mounted on the printed wiring board 11 via the strain absorbing portion 18c of the electrode body 18 without changing the mounting height of the leadless package from the conventional one. Therefore, the difference in the amount of expansion or contraction between the glass 6 and the printed wiring board 11 can be absorbed by the strain absorbing portion 18c. As a result, the glass 6 and the printed wiring board 11 can individually and freely expand or contract without being restrained by each other.
It is possible to prevent the occurrence of concentrated stress at the soldering part of a.

〔Example〕

1 to 4 are diagrams for explaining embodiments of the present invention. In these figures, parts that are the same as or equivalent to those shown in FIGS. 5 and 6 above are designated by the same reference numerals.

Figures 1 a, b, c, and d show the first embodiment, where a is a perspective view (partially cut away) and b is a view of a.
A sectional view taken along the line B ₁ -B ₂ , c is a partial perspective view of a section shown by arrow P in a, and d is a partially enlarged view of a section shown by arrow Q in b. FIG. 2 shows the first embodiment of FIG. 1 on a printed wiring board 11.
It is a figure which shows the form mounted on the top.

As shown in Figure 1, the vessel body 1 consists of iron, nickel,
A plate material such as cobalt alloy (commonly known as Kovar) is processed into a rectangular planar shape using a press molding machine.A flange portion 3 for attaching a lid 2 is formed on the periphery, and a flat surface is formed in the center. A recessed region 4 having a rectangular shape is formed. This recessed area 4 is the side wall 4
A and a side wall 4b, and four small holes 5, 5a for inserting electrode bodies are formed through the bottom wall 4a. Among these small holes 5 and 5a, three small holes 5 are formed to have a relatively large hole diameter, and one small hole 5a is formed to have a relatively large hole diameter. The glass 6 has concave portions made of glass powder that correspond to the outer and lower surfaces of the concave area 4 of the vessel body 1, and has small through holes (not shown) at positions corresponding to the small holes 5 and 5a of the vessel body 1. and a connecting flat part 18 of the electrode body 18
A notch 6a is provided at least in a portion corresponding to a, communicating with the small holes 5, 5a, and is press-molded in advance into a block shape. Then, this block-shaped glass 6 is fitted into the container body 1 from below, and then the vertical part 18 of the electrode body 18 is inserted into the four small holes 5, 5a.
The flat part 18a is placed at the same level as the lower surface 6b of the glass 6 at the notch 6a (actually, it protrudes slightly from the lower surface 6b), and this assembly is assembled into a carbon jig ( (not shown)
A conductive material (for example, silver solder) 7 is added to the inner lead portion of the electrode body 18 so that one of the four electrode bodies 18 (the electrode body inserted into the small holes 5, 5a) serves as a ground electrode. The glass 6 and the conductive material 7 are then heated and welded in a heating furnace (not shown) to obtain a hermetically sealed leadless package 20 as shown in FIG. 1b.

As shown in FIG. 1b, the glass 6 is sealed from the lower surface of the bottom wall 4a of the recessed region 4 of the container body 1 to the outer surface of the side wall 4b. In the electrode body 18, as shown in an enlarged view in FIG.
The portion adjacent to the flat portion is provided as a strain absorbing portion 18c, and the tip side of the vertical portion 18b penetrates the inside of the glass 6 and passes through the small holes 5, 5a of the vessel body 1. It extends over the vessel body 1. Further, as shown in FIG.
are respectively provided, and an upwardly bent portion 18g is provided at the free end of the flat portion 18a. Electrode body 18 passing through small hole 5a
The other electrode bodies 18 except for
The electrode body 18 passing through the small hole 5a is electrically connected to the container body 1 via the conductive material 7. The completed package 20 is loaded with a crystal element, an IC board, a composite element circuit board, and other elements, and is electrically connected to the electrode body 18.
The lid 2 is attached to the flange portion 3 of the container body 1 by a method such as resistance welding (projection welding, etc.), soldering, gold welding, laser welding, etc. (see FIG. 1a). Furthermore, the material of the glass 6 is as follows:
Glass with filler added to borokeitic acid powder glass,
Other suitable glasses or the like may be used. Further, as the metal material for the container body 1 and the electrode body 18, in addition to the above-mentioned Kovar, other materials that can be sealed with glass, such as copper-clad Kovar, iron-nickel alloy, etc., can be used.

The package 20 formed in this way is
As shown in the figure, it is mounted on a printed wiring board 11. In FIG. 2, reference numeral 12 indicates a conductor pattern formed on the printed wiring board 11, and 13
indicates solder. When mounting the package 20 on the printed wiring board 11, solder 13 is applied in advance to either the connection flat part 18a or the conductor pattern 12, and the flat part 13 is applied onto the conductor pattern 12.
8a are aligned and heated in a heating furnace (not shown) to melt the solder 13, thereby forming the flat portion 18.
Package 20 is mounted on printed wiring board 11 by soldering a onto conductor pattern 12. Therefore, in this example, the above-mentioned conventional example (6th
In contrast to FIG. 3, the glass 6 is indirectly attached onto the printed wiring board 11 via the strain absorbing portion 18c of the electrode body 18.

In this example, the mounting height is the same as that of the conventional example (FIGS. 5 and 6), and as described above, the glass 6 is indirectly mounted on the printed wiring board 11 via the strain absorbing portion 18c of the electrode body 18. It is structured so that it can be implemented in As a result, in this example, even if the difference in thermal expansion coefficients between the glass 6 and the printed wiring board 11 is large, the difference in the amount of expansion or contraction between the two can be absorbed by the strain absorbing portion 18c of the electrode body 18. . Therefore, in this example, the glass 6 and the printed wiring board 11 can independently and freely expand or contract without being constrained by each other. Therefore, this example can prevent the occurrence of concentrated stress in the glass 6, printed wiring board 11, soldered parts, etc., and as a result, cracks in the soldered parts 13, peeling/disconnection of the conductive pattern 12, and electrode It is possible to reliably prevent destruction of the fused interface between the body 18 and the glass 6 and the occurrence of cracks in the glass 6 itself. Further, in this example, through holes 18d and 18e are provided in the connecting flat part 18a and strain absorbing part 18c of the electrode body 18, respectively, and an upwardly bent part 18 is provided in the free end of the flat part 18a.
By providing the groove g, the excess solder 13 during soldering stays in the hole 18d and escapes to the upwardly bent portion 18g, thereby reducing excess solder that tries to enter the strain absorbing portion 18c. In addition, the holes 18e can prevent the solder 13 from entering the strain absorbing portion 18c. That is, the solder 13 enters and adheres to the strain absorbing portion 18c, which reduces the flexibility of the strain absorbing portion 18c, or in other words, increases the rigidity of the strain absorbing portion 18c. The absorbability of the amount of deformation of No. 11 decreases. Therefore, by forming the electrode body 18 as described above to prevent the solder 13 from entering the strain absorbing portion 18c, the effects of the present example described above can be further enhanced.

FIGS. 3a and 3b are diagrams showing the second embodiment,
A is a cross-sectional view thereof, and b is a partially enlarged view of the arrow Q portion in a. In this example, a notch 6a of the glass 6 is formed extending from the lower surface to the outer surface of the glass 6, a bent portion is provided in the middle of the vertical portion 18b of the electrode body 18, and a bent portion adjacent to the flat portion 18a is formed. The main difference from the first embodiment (FIGS. 1 and 2) is that it is formed as a strain absorbing section 18c, and the free end of the connecting flat section 18a is located inside the glass 6.
Other aspects are formed in the same manner as in the first embodiment. In this example, since the electrode body 18 is formed by bending in the middle, it is necessary to form the glass 6 thicker than the glass 6 of the first example.
8 and the glass 6 to increase the adhesion strength and airtightness between the two, and the length of the strain absorbing portion 18c can be increased to increase the strain absorbing capacity. Other functions and effects are the same as in the first embodiment.

FIGS. 4a, 4b and 4c are perspective views showing the main parts of the third, fourth and fifth embodiments, respectively.

In the third embodiment shown in FIG. 4a, a lower bent portion 18h is provided at the free end of the flat portion 18a of the electrode body 18, and the lower bent portion 18h allows the flat portion to
8a can be secured at a constant height on the printed wiring board 11 (FIG. 2). Therefore, in this example, the solder 13 is retained between the printed wiring board 11 and the flat portion 18a, and the surplus solder toward the strain absorbing portion 18c can be reduced. The operation and effect are the same as in the first embodiment.

Next, a fourth embodiment shown in FIG. 4b is formed by removing the upwardly bent portion 18g provided at the free end of the flat portion 18a in the first embodiment (FIGS. 1 and 2). Although the reduction of the surplus solder toward the strain absorbing portion 18c is slightly inferior to that of the first embodiment, it has the advantage that the electrode body 18 has a simple structure, and other effects are similar to those of the first embodiment. Similar to the example.

Next, in the fifth embodiment shown in FIG. 4c, the hole 18d of the flat portion 18a in the above-mentioned embodiment of FIG.
It is formed by providing a through hole 18f that is continuous with the hole 18e of the strain absorbing portion 18c, and its operation and effect are the same as those of the fourth embodiment.

Although the illustrated embodiments have been described above, the present invention is not limited to the embodiments described above, and is of course applicable to various modifications based on the gist of the present invention.

〔Effect of the invention〕

As explained above, according to the present invention, the glass 6 is attached to the printed wiring board 1 through the strain absorbing portion 18c of the electrode body 18 without changing the mounting height from the conventional one.
1, the difference in the amount of expansion or contraction between the glass 6 and the printed wiring board 11 can be reliably absorbed by the strain absorbing portion 18c. 11 can individually and freely perform expansion or contraction operations without being constrained by each other. Therefore, according to the present invention, it is possible to prevent the occurrence of concentrated stress at the soldered portions of the glass 6, the printed wiring board 11, the flat portion 18a, etc., and prevent cracks in the soldered portions 13 and peeling of the conductor pattern 12.・Disconnection, electrode body 18
A favorable effect is obtained in that destruction of the fused interface between the glass 6 and the glass 6 and generation of cracks in the glass 6 itself can be reliably prevented. Further, as shown in each of the above embodiments, through holes 18d, 18e, 18f and upper/lower bent portions 18g, 18h may be appropriately provided in the connecting flat portion 18a and strain absorbing portion 18c of the electrode body 18. Accordingly, the effects of the present invention described above can be further enhanced.

[Brief explanation of drawings]

1a, b, c, and d are diagrams showing a first embodiment of the present invention, FIG. 2 is a diagram showing a form in which the first embodiment of FIG. 1 is mounted on a printed wiring board 11, and FIG. Figures a, b are views showing the second embodiment of the present invention, Figures 4 a, b, and c are perspective views showing main parts of the third, fourth, and fifth embodiments of the present invention, and Figures 5 a, b is a diagram showing a conventional example, and FIG. 6 is a diagram showing a form in which the conventional example of FIG. 5 is mounted on a printed wiring board 11. In Figures 1, 2, 3, and 4, 20 is a leadless package according to the present invention, 1 is a container body, 2 is a lid, 3 is a flange portion, 4 is a concave area, 5 and 5a are small holes 5, and 6 are Glass, 6a is a notch, 6b is a lower surface, 7 is a conductive material, 11 is a printed wiring board, 12
1 is a conductor pattern, 13 is solder, 18 is an electrode body, 1
8a is a connecting flat part, 18b is a vertical part, 18c is a strain absorbing part, 18d, 18e, 18f are through holes,
18g and 18h are the upper bent part and the lower bent part,
are shown respectively.

Claims (1)

[Scope of Claims] 1. A container body 1 made of a metal plate and having a flange portion 3 around it for attaching a lid 2; A glass 6 as an insulating material provided at least on the lower surface of the container body 1; A vertical portion 18 having a connecting flat portion 18a disposed on the lower surface 6b side of the glass 6 and extending onto the container body 1 through the inside of the glass 6 and the container body 1.
In a leadless package in which a plurality of electrode bodies 18 having an electrode body 18 and a plurality of electrode bodies 18 are sealed airtightly and insulated, the flat part 18a of the electrode body 18 is
A notch portion 6a is provided in at least a portion of the glass 6 corresponding to the flat portion 18a, and the notch portion 6a is adjacent to the flat portion 18a and the flat portion 18a. A leadless package characterized in that a part of the vertical part 18b is exposed from the glass 6, and the part of the vertical part 18b is provided as a strain absorbing part 18c. 2. The leadless package according to claim 1, wherein the electrode body 18 has through holes 18d and 18e in either or both of the flat portion 18a and the strain absorbing portion 18c. 3 The electrode body 18 has an upper bent portion 18g or a lower bent portion 18h at the free end of its flat portion 18a.
A leadless package according to claim 1 or 2, which has the following.