JPS6370449A - Leadless package - Google Patents

Abstract

PURPOSE:To ensure the absorption of difference in amounts in expansion and contraction between glass and a printed wiring board, by exposing a part of the vertical part of an electrode body, and providing a strain absorbing part. CONSTITUTION:A flat part 18a of an electrode body 18 is arranged at about the same level of a lower surface 6b of glass 6. A cut part 6a is provided at a part corresponding to at least the flat part 18a of the glass 6. A part of the flat part 18a and a part of a vertical part 18b neighboring the flat part 18a are exposed from the glass 6 at the cut part 6a. A part of the vertical part 18b is provided as a strain absorbing part 18c. Thus the glass 6 can be packaged on a printed wiring board 11 indirectly without changing a packaging height from a conventional device through the strain absorbing part 18c of the electrode body 18. Therefore, the difference in amounts of expansion and contraction of the glass 6 and the printed wiring board 11 can be absorbed with the strain absorbing part 18c. Thus the glass 6 and the printed wiring board 11 can be freely expanded and contracted independently without constraint to each other.

Description

[Detailed description of the invention] [Table of contents] - Overview - Industrial application field - Prior art (Figures 5 and 6) - Problems that the invention attempts to solve - Means for solving the problems・Function・Example (Fig. 1.2.3.4) ・Effects of the invention [Summary] A leadless package of an insulating hermetic seal (hermetic seal) type, which has a flat plate for connecting an electrode body (18). Part (1
8a) at approximately the same level as the lower surface (6b) of the glass (6), and at least the flat portion (18a) of the glass (6)
A notch (6a) is provided in a portion corresponding to the flat part (18a) and the flat part (18a) in the notch (6a).
By exposing a part of the electrode body vertical part (18b) adjacent to 18a) from the glass (6) and providing a part of the vertical part (18b) as a strain absorbing part (18c),
Without changing the mounting height from the conventional one (the above distortion absorbing part (1)
8c) Glass (6) via printed wiring board (11)
As a result, 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), and the glass (6)
This allows the printed wiring board (11) and the printed wiring board (11) to individually and freely expand or contract without being constrained by each other.

[Industrial application field]

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

Traditionally, hermetic puff cages are formed with a plurality of lead wires extending downward from the package body.
When mounting the puff cage on a printed wiring board, these lead wires are inserted into designated small holes on the printed wiring board, and soldered on the back side of the printed wiring board using an automatic soldering device. Ta. In such packages, it is necessary to make small holes in the printed wiring board.
There are problems such as the small holes not being filled with enough solder 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 is also the problem that it is 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 puff cage and can be directly connected to printed wiring boards, and these leadless packages have come into widespread use.

[Conventional technology]

FIG. 5 is a diagram showing a conventional leadless package, ta+ is a perspective view (partially cut away), and (b) is a (al
FIG. 6 is a cross-sectional view taken along line A1 to A2 of FIG. 6, and is a diagram showing a form in which the conventional example of FIG. 5 is mounted on a printed wiring board (11).

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 concave area 4
has a bottom wall 4a, and four small holes 5 (5a) through which electrode bodies are inserted are formed through the bottom wall 4a. Among these small holes 5 (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 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 press-molded in advance into a block shape. Then, this block-shaped glass 6 is fitted into the container l from below, and then the electrode body 8 is inserted into the four small holes 5, 5a.
This assembly is stored in a carbon jig (not shown), and its inner lead is inserted so that one of the four electrode bodies 8 (the electrode body inserted into the small hole 5a) serves as a ground electrode. A conductive material (for example, silver solder) 7 is added to the part, and the glass 6 and the electrically conductive material 7 are heat-welded in a heating furnace (not shown) to form a hermetically sealed leadless package as shown in Fig. 5 (see Fig. 5). 10 is obtained.

As shown in FIG. 5(b), the glass 6 is connected to the bottom wall 4 of the container body 1.
It is sealed from the lower surface of the side wall 4a 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 penetrates the inside of the glass 6.
It extends onto the vessel body 1 through the small holes 5, 5a. Small hole 5
The other electrode bodies 8 except the ground electrode body passing through a are insulated from the vessel body 1 via the glass 6, and the ground electrode body 8 passing through the small hole 5a is insulated from the vessel body 1 through the conductive material 7. electrically connected. The completed puff cage 10 is loaded with a crystal element, an IC board, a composite element circuit board, and other elements, and is connected to the electrode body 8, after which M2 is attached to the container body 1 by a method such as resistance welding.

The package 10 formed in this way is mounted on a printed wiring board 11, as shown in FIG. In FIG. 6, reference numeral 12 indicates a conductor pattern provided on the printed wiring board 11, and 13 indicates solder. package 1
When mounting 0 on a printed wiring board ll, half EE1
Solder 13 is applied in advance to either the conductor pattern 12 or the connection flat part 8a, the flat part 8a is aligned and arranged on the conductor pattern 12, and the solder 13 is heated in a heating furnace (not shown). By melting, the package 10 is soldered onto the printed wiring board 11. In this conventional example,
Since the glass 6 is directly attached to the printed wiring board 11 via the flat portion 8a, 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, the glass 6 is connected to the printed wiring board 11.
Since the glass 6 and the printed wiring board 11 are directly attached to each other via the electrode body 8 (flat portion 8a), the glass 6 and the printed wiring board (board material ) 11 due to the difference in the amount of thermal expansion (or the amount of contraction during cooling), concentrated stress acts, causing cracks in the soldering parts, peeling of the conductor pattern (12), etc.
Disconnection, destruction of the fused interface between the electrode body (8) and the glass (6),
There is a problem in that the glass (6) itself tends to crack. 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 for the package and the printed wiring board have large coefficients of thermal expansion. The purpose is to

[Means for solving problems]

In the present invention, as a means to solve the above problems,
As illustrated in FIG. 1, a container body (1) made of a metal plate and having a flange portion (3) around the periphery for attaching the lid (2), and provided at least on the lower surface of the container body (1). It has a glass (6) as an insulating material, and a connecting flat part (18a) disposed on the lower surface (6b) side of the glass (6), and the inside of the glass (6) and the container body (1). A leadless package in which a plurality of electrode bodies (18) having vertical portions (18b) penetrating through and extending onto the vessel body (1) are hermetically and insulated sealed; A flat part (18a) of the glass (6) is arranged at approximately the same level as the lower surface (6b) of the glass (6), and a cutout part (6a) is provided in at least a portion of the glass (6) corresponding to the flat part (18a). The flat part (18a) and a part of the vertical part (18b) adjacent to the flat part (18a) are exposed from the glass (6) in the cutout part (6a), and the vertical part (18b) is Provided is a leadless package characterized in that a portion thereof is provided as a strain absorbing portion (18c).

Then, as illustrated in FIG. 1, the electrode body (18)
has through holes (18d, 18e) in either or both of the flat part (18a) and the strain absorbing part (18c).
It is preferable that it has.

Further, as illustrated in FIGS. 1 and 4, the electrode body (18
) has an upwardly bent portion (
18g) or a downwardly bent portion (18h).

[For production]

According to the above means according to the present invention, the glass (6) is attached to the printed wiring board (11) via the strain absorbing portion (18c) of the electric scraper (18) without changing the mounting height of the leadless package from the conventional one. ), the difference in the amount of expansion or contraction 1iIft between the glass (6) and the printed wiring board (11) can be absorbed by the strain absorbing portion (18c). This allows the glass (6) and the printed wiring board (11) to expand or contract independently and freely without being constrained by each other. Soldering can prevent the occurrence of concentrated stress in parts.

〔Example〕

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

Figures 1 (a), (b), (c), and (d) are views showing the first embodiment, where (a) is a perspective view (partially cut away) and (b) is a fa). B, -Bt line sectional view, (
C) is a partial perspective view of the second part in the direction of arrows in (a), (d) is a partial perspective view of (b)
FIG. 2 is a partially enlarged view of the arrow Q portion of FIG.

Figure 2 shows the first embodiment of Figure 1 as a printed wiring board (11).
It is a figure which shows the form mounted on the top.

As shown in Figure 1, the vessel l is made of a plate material such as iron-nickel-cobalt alloy (commonly known as Kovar) that is processed into a rectangular planar shape using a press molding machine. A flange portion 3 for attachment is formed, and a recessed region 4 having a rectangular planar shape is formed in the center. The recessed region 4 has a side wall 4a and a side wall 4b, and the bottom wall 4a is formed with four small holes 5 (5a) for inserting electrode bodies.

Among these small holes 5 (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 small hole diameter. The glass 6 has concave portions made of glass powder that correspond to the outer and lower surfaces of the concave region 4 of the vessel body 1, and a small through hole (not shown) at a position corresponding to the small hole 5° 5a of the vessel body 1. and a notch 6 at least in a portion corresponding to the connecting flat portion 18a of the electrode body 18.
A is provided to communicate with the small holes 5 and 5a, and is press-molded in advance into a block shape. Then, this block-shaped glass 6 is fitted into the vessel body 1 from below, and then the electrode body 18
The vertical portions 18b of the glass 6 are inserted into the four small holes 5.5a, and the flat portions 18a are placed so that the lower surfaces of the flat portions 18a are approximately on the same level as the lower surface 6b of the glass 6 at the cutout portions 6a (actually, they protrude slightly from the lower surface 6b). ), and this assembly is housed in a carbon jig (not shown), so that one of the four electrode bodies 18 (the electrode body inserted into the small holes 5, 5a) becomes a ground electrode. A conductive material (for example, silver solder) 7 is added to the inner lead portion, and the glass 6 and conductive material 7 are heat-welded in a heating furnace (not shown) to form a hermetically sealed lead as shown in FIG. 1 (bl). A less package 20 is obtained.

As shown in FIG. 1(b), 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. The electrode body 18 has a flat part 18a and a part adjacent to the flat part of the vertical part 18b adjacent to the flat part 18a exposed from the glass 6 at the cutout part 6a of the glass 6, as shown in the enlarged view in FIG. a portion adjacent to the flat portion is provided as a strain absorbing portion 18C;
In addition, the tip side of the vertical portion 18b penetrates the inside of the glass 6, passes through the small holes 5 and 5a of the vessel body 1, and extends onto the vessel body 1. Further, the electrode body 18 of this example, as shown in figure fc1,
Through holes 18d and 18e are provided in the flat portion 18a and the strain absorbing portion 18c adjacent to the flat portion 18a, respectively,
Further, an upwardly bent portion 18g is provided at the free end of the flat portion 18a. The other electrode bodies 18 except for the electrode body 18 passing through the small hole 5a are insulated from the container body 1 through the glass 6, and the electrode bodies 18 passing through the small hole 5a are insulated from the vessel body 1 through the conductive material 7. electrically connected to. The completed pancage 20 contains a crystal element, an IC board,
A composite element circuit board and other elements are mounted on the electrode body 1.
8, the lid 2 is connected to the flange portion 3 of the container body 1.
It is attached by resistance welding (projection welding, etc.), soldering, gold welding, laser welding, etc. (see FIG. 1(a)). As the material for the glass 6, a glass made of borosilicate powder glass containing a filler, or other suitable glass 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 craft Kovar, iron-nickel alloy, etc., can be used.

The puff cage 20 thus formed is secondly mounted on the printed wiring board 11 as shown in the figure. In FIG. 2, reference numeral 12 indicates a conductor pattern formed on the printed wiring board 11, and 13 indicates solder. When mounting the puff cage 20 on the printed wiring board 11, solder 1
3 is coated in advance on either the connection flat part 18a or the conductor pattern 12, the flat part 18a is aligned and arranged on the four-piece pattern 12, and the solder 13 is heated in a heating furnace (not shown). By melting, the puff cage 2 is soldered onto the conductive pattern 12 by soldering the flat part 18a onto the conductor pattern 12.
0 is mounted on the printed wiring board 11. Therefore, in this example, 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 when 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 glass 6 and the printed wiring board 11 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 perform an expansion or contraction action without being constrained by each other. Therefore, in this example, the glass 6
, printed wiring board 11, soldering can prevent the occurrence of concentrated stress at parts, etc., and as a result, soldering can prevent the occurrence of concentrated stress at parts (
13), peeling and disconnection of the conductor pattern 12, destruction of the fused interface between the electrode body 18 and the glass 6, and cracks in the glass 6 itself can be reliably prevented. Further, in this example, the connecting flat part 18a of the electrode body 18 and the strain absorbing part 18C
Through holes 18d and 18e are provided in the flat portion 18, respectively.
By providing the upwardly bent portion 18g at the free end of a, the surplus portion of the solder 13 during soldering stays in the hole 18d and escapes to the upwardly bent portion 18g to absorb distortion. It is possible to reduce excess solder that tries to enter the portion 18c, and to prevent the solder 13 from entering the strain absorbing portion 18c by the hole 18e. That is, when the solder 13 enters and adheres to the strain absorbing portion 18G, the flexibility of the strain absorbing portion 18c decreases, in other words, the strain absorbing portion 18C becomes rigid, and the glass 6 and the printed wiring board 11 absorbability of deformation 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.

FIG. 3 (at, (bl) is a diagram showing the second embodiment, ta+ is a cross-sectional view thereof, and ('b) is a partially enlarged view of the arrow Q portion of (al). Notch part 6a
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 the flat portion 18
The first embodiment (FIG. 1.2) differs in that the bent portion adjacent to a is formed as a strain absorbing portion 18G, and the free end of the connecting flat portion 18a is located inside the glass 6. This is the main difference from the first embodiment, and other aspects are formed in the same manner as the first embodiment.

In this example, since the electrode body 18 is formed by bending in the middle, the glass 6 needs to be formed thicker than the glass 6 of the first example, but the electrode body 18 and the glass 6 are This has the advantage that the area of the contact part can be increased to increase the adhesion strength and airtightness between the two, and the length of the strain absorbing part 18C can be increased to increase the strain absorbing capacity, and other effects. The effect is similar to that of the first embodiment.

Figure 4 (al, (b), (C) is 3.4.5
FIG. 3 is a perspective view showing main parts of the embodiment.

In the third embodiment shown in FIG. 4 (al), a lower bent portion 18h is provided at the free end of the flat portion 18a of the electrode body 18. (Fig. 2).For this reason, in this example, the solder 13 is retained between the printed wiring board 11 and the flat part 18a, and the strain absorbing part 18C This makes it possible to reduce the amount of excess solder that tends to the surface, and the other effects are the same as those of the first embodiment.

Next, in the fourth embodiment shown in FIG. 4Cb), the upper bent portion 18g provided at the free end of the flat portion 18a in the first embodiment (FIG. 1.2) is removed. It was formed,
The first step is to reduce the excess solder toward the distortion absorbing portion 18C.
Although it is slightly inferior to the example, it has the advantage that the electrode body 18 has a simple structure, and other effects are as good as the first example.
This is similar to the example.

Next, in the fifth embodiment shown in FIG. 4 (C1), a through hole 18f is provided in which the hole 18d of the flat part 18a in the above-mentioned embodiment of FIG. The 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 strain absorbing part (18) of the electrode body (18) can be
c) Plug the glass (6) through the lint wiring board (11)
Glass (6) because it can be mounted indirectly on top
The difference between the amount of expansion or contraction of the printed wiring board (11) and the printed wiring board (11) can be reliably absorbed by the strain absorbing portion (18c), so that the glass (6) and the printed wiring board (11) are not restrained from each other. It becomes possible to carry out the expansion or contraction action individually and freely. Therefore, according to the present invention, when soldering the glass (6), the printed wiring board (11), and the flat part (18a), it is possible to prevent the occurrence of concentrated stress in the parts, etc. ) cracks, conductor pattern (12
), breakage of the fused interface between the electrode body 18) and the glass (6), and cracking of the glass (6) itself can be prevented, which is a desirable effect. Further, as shown in each of the above embodiments, the through holes (18
d, 18e, 18F) and upper/lower bent portions (18g
, 18h) can be appropriately provided to further enhance the effects of the present invention described above.

[Brief explanation of the drawing]

Figure 1 (a), (b), (C1, (d) are diagrams showing the first embodiment of the present invention, Figure 2 shows the first embodiment of Figure 1 as a printed wiring board (11)
Figures 3(a) and (bl) are diagrams showing the second embodiment of the present invention, and Figures 4(al, (b), and (C) are diagrams showing the third embodiment of the present invention.
4.5 Perspective views showing the main parts of the embodiment, FIGS. 5(a) and 5(b) are views showing the conventional example, and FIG. 6 shows the conventional example of FIG. 5 on a printed wiring board (11). FIG. 3 is a diagram showing an implemented form. In Figures 1.2 and 3.4, 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, 5.5a is a small hole 5, and 6 is a Glass, 6a is a notch, 6b is a lower surface, 7 is a conductive material, 11 is a printed wiring board, 12 is a 4-piece pattern, 13 is solder, 18 is an electrode body, 18a is a flat part for connection, 18b is a vertical part, 18c is a strain absorption section, 18d, 18e
, 18f indicates a through hole, and 18g and 18h indicate an upper bent portion and a lower bent portion, respectively.

Claims (1)

[Claims] 1. A container body (1) made of a metal plate and having a flange portion (3) around the periphery for attaching a lid (2); and a container body (1) provided at least on the lower surface of the container body (1). It has a glass (6) as an insulating material and a connecting flat part (18a) arranged on the lower surface (6b) side of the glass (6) and penetrates inside the glass (6) and the container body (1). A leadless package in which a plurality of electrode bodies (18) having a vertical part (18b) extending above the container body (1) are hermetically and insulated sealed. (18a) to the glass (
6) is arranged at approximately the same level as the lower surface (6b), and a notch (6a) is provided in at least a portion of the glass (6) corresponding to the flat part (18a), and the notch (6a) , the flat part (18a) and a part of the vertical part (18b) adjacent to the flat part (18a) are exposed from the glass (6), and a part of the vertical part (18b) is formed into a strain absorbing part (
A leadless package characterized in that it is provided as 18c). 2. The electrode body (18) has a through hole (18d, 18e) in either or both of its flat part (18a) and strain absorbing part (18c). Leadless package as listed. 3. The electrode body (18) has an upwardly bent portion (18g) or a downwardly bent portion (18g) at the free end of its flat portion (18a).
h) Claim 1 or 2
Leadless packaging as described in section.