JPH10209331A - Electronic component storage package - Google Patents

Abstract

(57) [Summary] [PROBLEMS] When sealing an electronic component mounted on an electronic component mounting portion without lowering hermetic sealing performance, scattering of solder due to internal pressure of gas confined in the electronic component mounting portion is prevented. Provide a package for storing electronic components that can be prevented. SOLUTION: An electronic component housing package base has a lid fitting step portion for fitting the package sealing lid around an outer peripheral portion of the electronic component mounting portion. A frame-shaped metallized layer is provided on the bottom surface of the lid fitting step, and the inner end of the metalized layer is closer to the rising lower edge of the lid fitting step than the rising upper edge of the electronic component mounting portion. Located on the site. The outer edge of the lower surface of the lid body of the package sealing lid is located at a position closer to the rising upper edge of the electronic component mounting portion than the outer edge of the metallized layer. The thickness t of the solder layer of the package sealing lid and the depth d of the step portion for fitting the lid have a relationship of t ≦ d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a package for storing electronic components, and more particularly, to mounting an electronic component such as an IC chip or an LSI chip on an electronic component mounting portion of a package base, and mounting the electronic component. At the time of hermetic sealing, it prevents the scattering of solder due to the internal pressure of the gas trapped in the electronic component mounting part, and prevents the scattered solder from adhering to the package base, external connection terminals, etc., and becoming dirty. The present invention relates to an electronic component storage package that can be prevented.

[0002]

2. Description of the Related Art As shown in FIG. 5, an electronic component storage package includes an electronic component mounting portion 3 comprising a package base 1 and a concave portion (cavity) or opening of the package base 1.
The electronic component 4 mounted on the device is hermetically sealed with the package sealing lid 2. The package base 1 is made of a ceramic substrate or a resin substrate, has a metallized layer 5 on the upper surface of the base, and the package sealing lid 2 is made of a ceramic plate or a metal plate. A solder layer 8 is provided as a sealing member via a metal layer (not shown).

In order to hermetically seal the electronic component 4 mounted on the electronic component mounting portion 3 of the package base 1, a solder layer 8 of the package sealing lid 2 is provided on the upper surface of the package base 1. And the lid 2 is pressed and fixed to the package base 1 on which the electronic component 4 is mounted via a fixture such as a spring or a clip, and the solder of the solder layer 8 is melted in a furnace. It is sealed.

[0004]

However, in the case of a package for storing electronic parts as described above, the package base 1 is required.
There are the following problems when sealing the package by melting the solder layer 8 of the package sealing lid 2. That is, the melted solder of the solder layer 8 is scattered due to the expansion of the internal gas confined in the package, and the solder adheres to the surface of the package base 1, the external connection terminals 9, or between adjacent terminals. Therefore, the insertion of the external connection terminal 9 into the circuit mounting board is hindered, a short circuit occurs, and dirt is generated. Further, in order to reduce the influence of the solder scattering, it is necessary to cover the base surface of the package base 1, the external connection terminals 9, or the adjacent terminals with a jig, and it is necessary to clean the jig. And other issues.

In order to solve such a problem, the present applicant has previously described a method of providing a thickness gradient or a thickness difference in a solder layer of a package sealing lid or changing a solder width of the solder layer. Electronic Component Storage Package as Pattern "(see Japanese Patent Application No. 6-87571). This electronic component storage package can delay the sealing timing when sealing the electronic component mounting portion of the package base, so that the internal gas can be smoothly discharged to the outside of the package, and the gas scatters solder. Although it can be suppressed, it cannot be completely prevented.

[0006] In addition, another configuration is considered in which an upper surface of a package sealing lid is fitted into a package base so as to form a common flat surface, and this is joined and sealed with solder. However, in the case of this configuration, when sealing, there is a risk that the solder flows into the electronic component mounting portion, and a good meniscus shape of the solder cannot be formed between the side surface of the package sealing lid and the package base. And the need to increase the thickness of the package base.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to seal electronic components mounted on an electronic component mounting portion without deteriorating hermetic sealing performance. In this case, an object of the present invention is to provide an electronic component storage package that can prevent the scattering of solder due to the internal pressure of gas trapped in the electronic component mounting portion.

[0008]

According to a first aspect of the present invention, there is provided an electronic component storage package having an electronic component mounting portion including a recess or an opening. Electronic component storage package having a package base for packaging and a package sealing lid provided with a solder layer on a peripheral portion, the electronic component storage package base is provided on the outer peripheral portion of the electronic component mounting portion with the package sealing lid. A lid fitting step for fitting the lid, a frame-shaped metallized layer on a bottom surface of the lid fitting step, and an inner end of the metalized layer is higher than a rising upper edge of the electronic component mounting section. The package fitting lid is located at a position closer to the rising lower edge of the lid fitting step, and the outer edge of the lower surface of the lid main body of the package sealing lid is located at a lower end than the outer end of the metallized layer. Located at a site closer to the rising on the edge side of the component mounting portion, also the depth d of the the thickness t of the solder layer lid fitting step portion of the lid the package sealing
In a relationship of t ≦ d.

According to a second aspect of the present invention, there is provided a package for storing electronic parts.
In the invention of claim 1, a distance x between an inner end of the metallized layer and a rising upper edge of the electronic component mounting portion is defined as:
0.5 mm or more, and the distance y between the outer edge of the lower surface of the lid body of the package sealing lid and the outer end of the metallized layer is 0.5 mm or more, and the solder layer of the package sealing lid is The thickness t and the depth d of the lid fitting step are t <d, and a part of the lid body of the package sealing lid is fitted into the lid fitting step.

Here, the package sealing lid includes:
A ceramic plate or a metal plate is used as a lid body, and a solder layer is provided on a peripheral portion thereof. The peripheral portion refers to a lower peripheral portion or a lower peripheral portion and a side surface portion of the lid body. When the lid body is a ceramic plate, a solder layer is formed via a base metal layer. The underlying metal layer is made of Ag, Ag-
A paste containing a metal such as Pt, Ag-Pd, Mo-Mn, Mo, W, and Ti is applied and fired to form a metallized layer, and a solder layer is formed on the metallized layer. If the paste is Mo-Mn, Mo, W, Ti, the upper surface is plated with Ni, and the upper surface is further plated with Au. As the solder, for example, the melting point is 250 ° C.
At about 320 ° C., the composition is Pb, Sn, In, B
Solder containing a part or all of i, Ag, and Sb can be used.

The electronic component storage package according to the present invention is characterized in that an electronic component such as an IC chip is mounted on an electronic component mounting portion of a package base, wire bonding is performed, and then a metallized layer of a lid fitting step portion of the package base is provided. To
With the package sealing lid facing the solder layer, the package sealing lid is fitted, pressed and fixed via a fixture such as a spring or clip, and the solder of the solder layer is melted and sealed in a furnace. The solder wets and spreads on the metallized layer of the package base, forms a good meniscus shape on the periphery of the lid, and can hermetically seal the electronic component mounting portion.

[0012]

As is apparent from the above description, according to the electronic component housing package of the first aspect of the present invention, the inner end of the metallized layer of the package base is located closer to the rising upper edge of the electronic component mounting portion. Since it is in the lowered position, it does not flow down into the electronic component mounting portion, and the outer edge of the lower surface of the lid body of the package sealing lid is located closer to the electronic component mounting portion than the outer end of the metallized layer, so that a good meniscus is provided. The solder blown by the internal pressure gas of the electronic component mounting portion can be prevented from being scattered by the rising wall of the step portion for lid fitting, so that the scattered solder is attached to the package base. This has the effect of preventing adhesion to connection terminals and the like and ensuring airtight sealing.

According to the electronic component storage package of the present invention, the interval x, that is, the down width of the metallization layer is 0.5 mm or more, and the interval y, that is, the wet spread width of the solder is 0.5 mm or more, Since the thickness t of the solder layer and the depth d of the step portion for fitting the lid are set as t <d,
In addition to the above-mentioned effects, there is an effect that it is possible to further solve the problem of electronic components and external connection terminals due to soldering without increasing the thickness of the package body.

[0014]

Preferred embodiments of the present invention will be described below with reference to the drawings.
1 to 4 show an embodiment of the present invention.
2 is a longitudinal sectional view, FIG. 2 is a plan view of a package base, FIG. 3 is a graph showing a relationship between the height of a rising wall of a step portion for lid fitting and a defect occurrence rate due to solder scattering, and FIG. 4 is a portion A in FIG. And FIG. It should be noted that the present invention is not limited to the description of the embodiments described below, and it is clear that the present invention includes configurations that can be modified and implemented without departing from the gist of the present invention.

As shown in FIGS. 1 and 2, the electronic component housing package of this embodiment comprises a ceramic package base 10 and a package sealing lid 11.
The package base 11 includes an electronic component mounting portion 13 formed of a concave portion for mounting an electronic component 14 such as an IC chip in a central portion of the surface, and a package sealing lid 11 for hermetically sealing the electronic component mounting portion 13. A lid fitting step 15 for fitting is provided, and an external connection terminal 16 is provided. The electronic component mounting unit 13 includes a wire bonding pattern for electrically connecting the electronic component mounting surface 13a to which the electronic component 14 is bonded and the electronic component 14 to the external connection terminal 16 via an internal wiring pattern (not shown). It has the provided wire bonding surface 13b.

The step portion 15 for fitting the lid is provided on the outer peripheral portion of the electronic component mounting portion 13, and a frame-shaped metallized layer 17 is formed on the step bottom surface 15a. Metallization layer 17
Are Ag, Ag-Pt, Ag-Pd, Mo-Mn, M
A paste containing a metal such as o, W, and Ti is applied and fired to form the paste, and the paste is made of Mo-Mn, Mo, W, T
In the case of i, the upper surface is plated with Ni, and the upper surface is further plated with Au. The inner end a of the metallized layer 17 is located at a position closer to the lower edge c of the rising wall 19 of the step portion 15 for lid fitting from the upper edge b of the rising wall 18 of the electronic component mounting portion 13. The outer end e of the metallized layer 17 is connected to the package sealing lid 11.
Is formed at a position closer to the lower edge c side of the rising wall 19 of the step portion 15 for fitting the lid from the outer edge f of the lower surface of the lid body 20. That is, the metallized layer 1
7 is formed such that a part of the metallized layer 17 is exposed on the outer periphery of the package sealing lid 11 when the package sealing lid 11 is fitted into the lid fitting step portion 15. Here, the inner end a of the metallized layer 17
It is preferable that the distance x between the lower edge and the upper edge b of the rising wall of the electronic component mounting portion 13 is 0.5 mm or more. Thereby, at the time of solder sealing, it is possible to prevent problems such as the solder flowing down into the electronic component mounting portion 13 due to the spread of the solder and short-circuiting of the wire bonding pattern. The reason why the interval x is set to 0.5 mm or more is to consider that if the interval x is smaller than 0.5 mm, the solder may flow down into the electronic component mounting portion 13 depending on the type of solder. The distance y between the outer edge e of the metallization layer 17 and the outer edge f of the lower surface of the lid body 20 of the package sealing lid 11 is preferably 0.5 mm or more.
If the width is smaller than 0.5 mm, it is considered that a good meniscus shape of the solder cannot be formed, and good hermetic sealing cannot be ensured.

The package sealing lid 11 includes a ceramic plate and a solder layer 24 formed on a lower peripheral portion 21 and a side surface 22 of a lid body 20 with a base metal layer 23 interposed therebetween. Here, the thickness t of the solder layer 24 and the step portion 15
And the depth d of the rising wall 19 has a relationship of t ≦ d. Preferably, the relationship is such that a part of the lid body 20 of the package sealing lid 11 can be fitted in the lid fitting step 15 as t <d. Thereby, when the package base 10 is sealed with the solder layer 24 formed on the lid 11, a good solder meniscus shape is obtained between the lid 11 and the metallized layer 17 of the package base 10, and the sealing property is improved. In addition, the rising of the solder by the rising wall 19 can prevent the solder blown off by the internal gas at the time of sealing from scattering outside the package. Here, the base metal layer and the solder layer on the side surface portion 22 are not necessarily required. By the way, as the solder for forming the solder layer 24, a solder having a melting point of about 250 ° C. to 320 ° C. and containing a part or all of Pb, Sn, In, Bi, Ag, and Sb can be used. The metal paste for forming the base metal layer 23 has the same form as the metallized layer 17 in the package base 10.

The electronic component housing package of the present embodiment is provided on the electronic component mounting surface 13a of the package base 10.
After the electronic component 14 is mounted on the package base 10 and the electronic component 14 and the wire bonding pattern on the wire bonding surface 13b are connected by bonding wires,
The package sealing lid 11 is fitted with the solder layer 24 of the package sealing lid 11 opposed to the metallized layer 17 of the lid fitting step portion 15, and pressed and fixed via a fixing tool such as a spring or a clip. Then, the solder of the solder layer 24 is melted in a furnace, and the solder is wetted and spread by the metallized layer 17 to form a good meniscus shape.
4 can be hermetically sealed. By the way, when the electronic component mounting portion 13 is sealed, the gas inside the electronic component mounting portion 13 expands due to heat and tends to escape to the outside, but the gas escapes due to the solder wet and spread on the metallization layer 17. And the solder is scattered. However, the scattered solder can be prevented from being scattered outside the package by the rising wall 19 that forms the step portion 15 for lid fitting. The molten solder spreads on the metallized layer 17, but the inner end a of the metallized layer 17
And the distance x between the rising edge b of the electronic component mounting portion 13 and the upper edge b of the electronic component mounting portion 13 is 0.5 mm or more, so that the solder flows down into the electronic component mounting portion 13 to short-circuit the wire bonding pattern. Can be prevented.

[0019]

EXAMPLE Next, in order to confirm the operation and effect of the electronic component storage package of the present embodiment described above, in the package of the form shown in FIGS. : 0.2 mm, width of solder layer:
A lid made of a ceramic plate having a size of 0.25 mm and a length and width of 33 mm × 33 mm was used. As a package base, pulling-down intervals x: 0.7 mm, 0.5 mm, 0.
4 mm, interval y: 0.7 mm, 0.5 mm, 0.4 m
m, depth d of the rising wall of the step portion for lid insertion: 0 m
The relationship between the depth d of the rising wall of the step portion for lid fitting and the defect occurrence rate due to solder scattering was examined using a plurality of types of ceramic package bases having different sizes of m to 0.25 mm. The results are shown in FIG.

As shown in FIG. 3, the thickness t of the solder layer of the package sealing lid and the depth d of the step portion for fitting the lid satisfy t ≦ d, and the inner end of the metallization layer and the electronic component When a pull-down interval is provided between the rising edge of the mounting part and the outer edge of the lower surface of the lid body of the package sealing lid is positioned closer to the electronic component mounting part than the outer edge of the metallization layer, solder scattering may occur. It was confirmed that the failure rate can be reduced.

Further, from Table 1, when x is 0.5 mm or more, it is possible to prevent the solder from flowing into the cavity, and to set y to 0.5 mm.
It was found that a good meniscus shape can be formed when the thickness is not less than mm.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electronic component housing package according to an embodiment of the present invention.

FIG. 2 is a plan view of a package base.

FIG. 3 is a graph showing a relationship between a height of a rising wall of a step portion for lid fitting and a failure occurrence rate due to solder scattering.

FIG. 4 is an enlarged view of a portion A and a portion B of FIG.

FIG. 5 is a longitudinal sectional view of a conventional electronic component storage package.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Package base, 11 ... Package sealing lid, 13 ... Electronic component mounting part, 13a ... Electronic component mounting surface, 13b ... Wire bonding surface, 1
4 ・ ・ ・ Electronic component, 15 ・ ・ ・ Step portion for lid insertion, 1
5a: step bottom, 16: external connection terminal, 17
..Metalized layer, 18 ... Rising wall of electronic component mounting portion 13, 19 ... Rising wall of step portion 15 for lid fitting, 20 ... Lid body, 21 ... Peripheral edge of lower surface of lid body, 22 ... side part of lid body, 23
... underlying metal layer, 24 ... solder layer, a ... inner end of metallization layer 17, b ... upper edge of rising wall 18, t ... solder thickness, d ... lid fit Step 15
Depth of the rising wall 19, c ... rising wall 19
Lower edge, e... Outer edge of metallization layer 17, f.
Outer edge of lower surface of lid body, 1 ... package base, 3
..Electronic component mounting part, 4 ... Electronic component, 2 ... Lid for package sealing, 5 ... Metalized layer, 6 ...
Lower peripheral edge, 8: solder layer, 9: external connection terminal

[Table 1]

Claims (2)

[Claims] 1. An electronic component storage package having a package base having an electronic component mounting portion formed of a concave portion or an opening and a package sealing lid having a solder layer on a peripheral portion thereof. Has a lid fitting step for fitting the package sealing lid on an outer peripheral portion of the electronic component mounting portion, has a frame-shaped metallized layer on the bottom surface of the lid fitting step, and has the metallized layer. Is located at a position closer to the rising lower edge of the lid fitting step than the rising upper edge of the electronic component mounting portion, and the lower edge of the lower surface of the lid body of the package sealing lid is The thickness t of the solder layer of the package sealing lid and the height difference between the lid fitting step and the outer edge of the metallization layer, which are closer to the rising upper edge side of the electronic component mounting portion. An electronic component storage package, wherein the depth d of the portion is set to satisfy a relation of t ≦ d. 2. A distance x between an inner end of the metallization layer and a rising upper edge of an electronic component mounting portion is 0.5 mm or more, and a lower surface outer edge of a lid body of the package sealing lid and a metallization. The distance y from the outer edge of the layer is 0.5
mm or more, and the thickness t of the solder layer of the package sealing lid and the depth d of the lid fitting step are t <d,
The electronic component storage package according to claim 1, wherein a part of a lid body of the package sealing lid is fitted into the lid fitting step.